Fluke RPM4 User Manual

RPM4™

Reference Pressure Monitor

Operation and Maintenance Manual

TABLE OF CONTENTS

TABLE OF CONTENTS ............................................................... I

TABLES .................................................................................. V

FIGURES................................................................................ VI

ABOUT THIS MANUAL ............................................................ VII

1. INTRODUCTION ................................................................. 1

1.1

1.2

PRODUCT OVERVIEW ...........................................................................................................................1

SPECIFICATIONS ...................................................................................................................................2

1.2.1

GENERAL SPECIFICATIONS.......................................................................................................................2

PRESSURE MEASUREMENT SPECIFICATIONS........................................................................................2

QUARTZ REFERENCE PRESSURE TRANSDUCER (Q-RPT) ................................................................2

ON-BOARD BAROMETER ........................................................................................................................4

BATTERY AND CHARGER PACK................................................................................................................5

1.2.2

1.2.2.1

1.2.2.2

1.2.3

2. INSTALLATION .................................................................. 7

2.1

UNPACKING AND INSPECTION ............................................................................................................7

2.1.1

2.1.2

REMOVING FROM PACKAGING..................................................................................................................7

INSPECTING CONTENTS.............................................................................................................................7

2.2

2.3

SITE REQUIREMENTS............................................................................................................................8

SETUP .....................................................................................................................................................8

2.3.1

PREPARING FOR OPERATION ...................................................................................................................8

FRONT AND REAR PANELS........................................................................................................................8

FRONT PANEL ..........................................................................................................................................8

REAR PANEL.............................................................................................................................................9

POWER CONNECTION.................................................................................................................................9

85 TO 264 VAC, 50/60 HZ VAC POWER ..................................................................................................9

BATTERY PACK ........................................................................................................................................9

REMOTE [ENT] CONNECTION (FOOTSWITCH OR OTHER SWITCH)....................................................10

CONNECTING TO MEASURE PRESSURE (TEST(+) AND TEST(-) PORTS)...........................................10

THE VENT OR ATM PORT..........................................................................................................................11

CHECK/SET SECURITY LEVEL.................................................................................................................11

TURN OFF ABSOLUTE AND NEGATIVE GAUGE MODE (AXXX RPT)....................................................12

SDS FULL TIME OFF ..................................................................................................................................12

PARALLEL MEASUREMENT MODE..........................................................................................................12

2.3.2

2.3.2.1

2.3.2.2

2.3.3

2.3.3.1

2.3.3.2

2.3.4

2.3.5

2.3.6

2.3.7

2.3.8

2.3.9

2.3.10

2.4

2.5

POWER-UP AND VERIFICATION.........................................................................................................12

2.4.1

2.4.2

2.4.2.1

2.4.2.2

SWITCH POWER ON ..................................................................................................................................12

CHECK PRESSURE MEASUREMENT OPERATION.................................................................................13

CHECKING ABSOLUTE MODE PRESSURE MEASUREMENT.............................................................13

CHECKING GAUGE MODE PRESSURE MEASUREMENT...................................................................13

SHORT TERM STORAGE.....................................................................................................................14

3. OPERATION ..................................................................... 15

3.1

3.2

USER INTERFACE................................................................................................................................15

3.1.1

3.1.2

3.1.3

3.1.4

MAIN RUN SCREEN....................................................................................................................................15

FUNCTION / DATA KEYPAD LAYOUT AND PROTOCOL.........................................................................17

REMOTE [ENT] (ENTER) FOOTSWITCH...................................................................................................18

SOUNDS ......................................................................................................................................................18

GENERAL OPERATING PRINCIPLES .................................................................................................18

3.2.1

PRESSURE READY/NOT READY ..............................................................................................................18

Page I

RPM4™ OPERATION AND MAINTENANCE MANUAL

3.2.2

GAUGE AND NEGATIVE GAUGE MODES WITH AN AXXX (ABSOLUTE) Q-RPT, DYNAMIC

COMPENSATION FOR ATMOSPHERIC PRESSURE ...............................................................................19

MULTIPE RANGES (Q-RPTS, AUTORANGE AND INFINITE RANGING) .................................................19

PARALLEL MEASUREMENT MODE..........................................................................................................21

USING RPM4 WITH A PPC3 CONTROLLER/CALIBRATOR.....................................................................21

USE OF THE 12VDC BATTERY/CHARGER PACK ...................................................................................23

SDS SELF DEFENSE SYSTEM ..................................................................................................................24

DIRECT FUNCTION KEYS SUMMARY ......................................................................................................25

3.2.3

3.2.4

3.2.5

3.2.6

3.2.7

3.2.8

3.3

DIRECT FUNCTION KEYS....................................................................................................................25

3.3.1

[RANGE] ......................................................................................................................................................25

[UNIT]...........................................................................................................................................................26

[MODE] ........................................................................................................................................................27

DIFFERENTIAL MEASUREMENT MODE OPERATION.........................................................................29

[AUTORANGE] ............................................................................................................................................30

[LEAK CK] ...................................................................................................................................................33

[DISPLAY]....................................................................................................................................................34

AVG (AVERAGE).....................................................................................................................................36

RATE........................................................................................................................................................37

DEV (DEVIATION) ...................................................................................................................................38

RPT ..........................................................................................................................................................39

HI/LO........................................................................................................................................................40

FREEZE ...................................................................................................................................................41

CLEAN .....................................................................................................................................................41

[HEAD].........................................................................................................................................................42

[SDS] (SELF DEFENSE SYSTEM) .............................................................................................................43

SDS IN DIFFERENTIAL AND PARALLEL MEASUREMENT MODES....................................................46

[AUTOZ].......................................................................................................................................................46

[AUTOZ] IN GAUGE AND NEGATIVE GAUGE MODE ...........................................................................47

[AUTOZ] IN ABSOLUTE MODE...............................................................................................................48

AUTOZ IN DIFFERENTIAL MODE ..........................................................................................................51

[ENT] (RUN AUTOTEST).............................................................................................................................51

3.3.2

3.3.3

3.3.3.1

3.3.4

3.3.5

3.3.6

3.3.6.1

3.3.6.2

3.3.6.3

3.3.6.4

3.3.6.5

3.3.6.6

3.3.6.7

3.3.7

3.3.8

3.3.8.1

3.3.9

3.3.9.1

3.3.9.2

3.3.9.3

3.3.10

3.4

3.5

[SETUP].................................................................................................................................................52

3.4.1

<1RANGE> ..................................................................................................................................................52

SAVING AN AUTORANGE RANGE ........................................................................................................52

DELETING AUTORANGE RANGES........................................................................................................53

<2RES> (RESOLUTION).............................................................................................................................53

<3STAB>......................................................................................................................................................54

<4UL> (UPPER LIMIT) ................................................................................................................................55

OVER PRESSURE FUNCTION...............................................................................................................57

<5ATEST>....................................................................................................................................................57

3.4.1.1

3.4.1.2

3.4.2

3.4.3

3.4.4

3.4.4.1

3.4.5

[SPECIAL] .............................................................................................................................................57

3.5.1

3.5.1.1

3.5.2

3.5.2.1

3.5.2.2

3.5.2.3

3.5.2.4

3.5.3

<1AUTOZ>...................................................................................................................................................58

EDIT AUTOZ ............................................................................................................................................62

<2REMOTE>................................................................................................................................................62

<1COM1, 2COM2>...................................................................................................................................63

<3IEEE-488>............................................................................................................................................63

<4FORMAT> ............................................................................................................................................63

<5RS232 SELF-TEST>............................................................................................................................64

<3HEAD> .....................................................................................................................................................64

<4SDS>........................................................................................................................................................65

<1TEMP OPEN/CLOSE>.........................................................................................................................65

<2FULL TIME ON/OFF> ..........................................................................................................................66

<5PREFS> ...................................................................................................................................................66

<1SCRSVR> ............................................................................................................................................67

<2SOUND> ..............................................................................................................................................67

<3TIME>...................................................................................................................................................67

<4ID>........................................................................................................................................................68

<5LEVEL> (SECURITY)...........................................................................................................................68

<6PUNIT>.....................................................................................................................................................71

<7INTERNAL> .............................................................................................................................................73

<1BARO>.................................................................................................................................................73

<2READRT> ............................................................................................................................................74

<3RPT2X>................................................................................................................................................75

<4LO VNT> ..............................................................................................................................................76

<5LOG>....................................................................................................................................................77

<8CAL>........................................................................................................................................................77

<9RESET> ...................................................................................................................................................78

<1SETS>..................................................................................................................................................78

<2 UNITS> ...............................................................................................................................................79

<3ATEST>................................................................................................................................................79

<4 CAL> ...................................................................................................................................................79

<5 ALL>....................................................................................................................................................80

3.5.4

3.5.4.1

3.5.4.2

3.5.5

3.5.5.1

3.5.5.2

3.5.5.3

3.5.5.4

3.5.5.5

3.5.6

3.5.7

3.5.7.1

3.5.7.2

3.5.7.3

3.5.7.4

3.5.7.5

3.5.8

3.5.9

3.5.9.1

3.5.9.2

3.5.9.3

3.5.9.4

3.5.9.5

Page II

TABLE OF CONTENTS

4. REMOTE OPERATION ....................................................... 81

4.1

4.2

OVERVIEW............................................................................................................................................81

INTERFACING.......................................................................................................................................81

4.2.1

RS232 INTERFACE.....................................................................................................................................81

COM1.......................................................................................................................................................81

IEEE-488..................................................................................................................................................82

COM2.......................................................................................................................................................82

4.2.1.1

4.2.1.2

4.2.1.3

4.3

4.4

4.5

4.6

PROGRAMMING FORMATS.................................................................................................................82

4.3.1

4.3.2

4.3.2.1

4.3.2.2

CLASSIC PROGRAM MESSAGE FORMAT...............................................................................................83

ENHANCED PROGRAM MESSAGE FORMAT ..........................................................................................83

USING COMMAND TYPE COMMANDS .................................................................................................83

USING QUERY TYPE COMMANDS ...................................................................................................84

COMMANDS..........................................................................................................................................85

4.4.1

4.4.2

4.4.3

4.4.4

PROGRAMMING MESSAGES ....................................................................................................................85

ERROR MESSAGESS.................................................................................................................................86

PROGRAM MESSAGE DESCRIPTION OVERVIEW..................................................................................87

PROGRAM MESSAGE DESCRIPTIONS....................................................................................................88

STATUS REPORTING SYSTEM .........................................................................................................108

4.5.1

4.5.2

4.5.3

4.5.4

ERROR QUEUE.........................................................................................................................................108

STATUS BYTE REGISTER .......................................................................................................................108

STANDARD EVENT REGISTER ...............................................................................................................110

READY STATUS REGISTER ....................................................................................................................110

IEEE STD. 488.2 COMMON AND STATUS PROGRAM MESSAGES................................................111

4.6.1

PROGRAM MESSAGE DESCRIPTIONS..................................................................................................112

5. MAINTENANCE, ADJUSTMENTS AND CALIBRATION ................ 115

5.1

5.2

OVERVIEW..........................................................................................................................................115

CALIBRATION OF QUARTZ REFERENCE PRESSURE TRANSDUCERS (Q-RPTS) ......................115

5.2.1

PRINCIPLE ................................................................................................................................................115

PA AND PM COEFFICIENTS ................................................................................................................116

AS RECEIVED AND AS LEFT DATA ....................................................................................................116

EQUIPMENT REQUIRED ..........................................................................................................................117

GAS OPERATED Q-RPTS, A10M AND LOWER ..................................................................................117

OIL OR GAS OPERATED Q-RPTS A14M AND HIGHER .....................................................................117

SET-UP AND PREPARATION...................................................................................................................118

RECOMMENDED CALIBRATION POINT SEQUENCE............................................................................119

STANDARD CLASS Q-RPTS ................................................................................................................119

PREMIUM CLASS Q-RPTS ...................................................................................................................120

TURNING OFF ABSOLUTE AND NEGATIVE GAUGE MEASUREMENT MODES FOR AXXX

(ABSOLUTE) Q-RPTS .........................................................................................................................122

Q-RPT CALIBRATION USING CALTOOL FOR RPTS SOFTWARE........................................................122

EDITING AND VIEWING Q-RPT CALIBRATION INFORMATION............................................................122

Q-RPT CALIBRATION/ADJUSTMENT WITHOUT CALTOOL FOR RPTS SOFTWARE.........................124

5.2.1.1

5.2.1.2

5.2.2

5.2.2.1

5.2.2.2

5.2.3

5.2.4

5.2.4.1

5.2.4.2

5.2.5

5.2.6

5.2.7

5.2.8

5.3

5.4

5.5

ADJUSTMENT OF ON-BOARD BAROMETER...................................................................................125

RELOADING EMBEDDED SOFTWARE INTO FLASH MEMORY......................................................126

SUBASSEMBLY DESCRIPTION AND LOCATION ............................................................................127

5.5.1

5.5.2

5.5.3

5.5.4

5.5.5

5.5.5.1

5.5.5.2

5.5.6

MINI MICRO BOARD.................................................................................................................................127

POWER SUPPLY MODULE......................................................................................................................127

DRIVER BOARD........................................................................................................................................128

ON-BOARD BAROMETER........................................................................................................................128

Q-RPT MODULE........................................................................................................................................128

HI Q-RPT MODULE ...............................................................................................................................128

LO Q-RPT MODULE ..............................................................................................................................128

DISPLAY....................................................................................................................................................128

5.6

Q-RPT MODULE PNEUMATIC SCHEMATICS...................................................................................129

Page III

RPM4™ OPERATION AND MAINTENANCE MANUAL

6. TROUBLESHOOTING .......................................................131

7. APPENDIX ......................................................................135

7.1

7.2

REMOTE [ENT] ...................................................................................................................................135

UNIT CONVERSION............................................................................................................................136

7.2.1

PRESSURE................................................................................................................................................136

8. WARRANTY ....................................................................137

8.1

OVERVIEW..........................................................................................................................................137

9. GLOSSARY .....................................................................139

Page IV

TABLES & FIGURES

TABLES

Table 1. Reference Pressure Transducer (Q-RPT) Module Designations and Ranges ............................. 3

Table 2. RPM4 Packing List......................................................................................................................... 7

Table 3. Position Designators of Q-RPTs in an RPM4 System................................................................. 20

Table 4. Settings and What They Are Specific To (Range, Measurement Mode, Q-RPT, System) ......... 21

Table 5. Summary of RPM4 Function Key Operation................................................................................ 25

Table 6. Settings Made by AutoRange ...................................................................................................... 31

Table 7. AutoZ ON and OFF...................................................................................................................... 60

Table 8. Security Levels............................................................................................................................. 70

Table 9. UNIT Function - Available Units of Measure................................................................................ 72

Table 10. READRT - Display Update Rates.............................................................................................. 74

Table 11. Reset – Sets............................................................................................................................... 79

Table 12. Reset – Cal ................................................................................................................................ 80

Table 13. Reset – All.................................................................................................................................. 80

Table 14. COM1 Pin Designations and Connections ................................................................................ 81

Table 15. COM2 DB-9F Pin Designations................................................................................................. 82

Table 16. Program Message List............................................................................................................... 85

Table 17. Error #s and Descriptions .......................................................................................................... 86

Table 18. 8 Bit Status Byte Register........................................................................................................ 108

Table 19. 8 Bit Standard Event Register.................................................................................................. 110

Table 20. 8 Bit Ready Status Register..................................................................................................... 110

Table 21. Program Message List............................................................................................................. 111

Table 22. Calibration Point Sequence, Standard Class, Axxx and Gxxx Q-RPTs .................................. 119

Table 23. Calibration Point Sequence, Standard Class, BGxxx Q-RPTs................................................ 120

Table 24. Calibration Point Sequence, Standard Class, BA100K Q-RPT............................................... 120

Table 25. Calibration Point Sequence, Premium Class, Axxx and Gxxx Q-RPTs .................................. 121

Table 26. Calibration Point Sequence, Premium Class, BGxxx Q-RPTs................................................ 121

Table 27. Troubleshooting Guide............................................................................................................. 131

Table 28. Pressure Unit of Measure Conversion Coefficients.................................................................136

Table 29. DHI Authorized Service Providers ...........................................................................................137

Page V

RPM4™ OPERATION AND MAINTENANCE MANUAL

FIGURES

Figure 1. Front Panel ................................................................................................................................... 8

Figure 2. Rear Panel.................................................................................................................................... 9

Figure 3. MAIN RUN Screen Display Fields.............................................................................................. 16

Figure 4. Keypad Layout............................................................................................................................ 17

Figure 5. Battery Pack/Charger ................................................................................................................. 23

Figure 6. Status Register Schematic ....................................................................................................... 109

Figure 7. Internal View ............................................................................................................................. 127

Figure 8. Pneumatic/hydraulic schematics of RPM4 with Single Q-RPT Module ................................... 129

Figure 9. Pneumatic/hydraulic schematics of RPM4 with Two Q-RPT Modules..................................... 130

Figure 10. Remote [ENT] Connector Schematic ..................................................................................... 135

Page VI

ABOUT THIS MANUAL

This manual is intended to provide the user with the basic information necessary to operate an RPM4

reference pressure monitor. It also includes a great deal of additional information provided to allow you to

optimize RPM4 use and take full advantage of its many features and functions.

RPM4-AD is a special air data configuration of RPM4 which has its own dedicated manual, p/n

550148. This manual is for all other configurations of RPM4. If your are using an RPM4-AD (“-AD” in

front panel configuration window) use the RPM4-AD Operation and Maintenance Manual p/n 550148.

Before using the manual, take a moment to familiarize yourself with the Table of Contents structure:

Sections 1, 2 and 3 should be read by all first time RPM4 users. Section 3 is most important for those

using the local front panel interface but should be read over by all users to familiarize themselves with

general RPM4 operating principles. Section 4 is for remote operation from an external computer. Section 5

provides maintenance and calibration information. Section 6 is a quick troubleshooting guide. Use it to

troubleshoot unexpected RPM4 behavior based on the symptom of that behavior. Certain words and

expressions have specific meaning as they pertain to RPM4. The Glossary, Section 6, is useful as a

quick reference for exact definition of specific words and expressions as they are used in the manual.

For those of you who “don’t read manuals”, go directly to Section 2.3 to set up your RPM4 and then

go to Section 2.4 for power-up and verification. This will get you up and running quickly with a minimal

risk of causing damage to yourself or your new RPM4. THEN… when you have questions or start to

wonder about all the great features you might be missing, get into the manual!

Manual Conventions

(CAUTION) is used in throughout the manual to identify user warnings and cautions.

(NOTE) is used throughout the manual to identify operating and applications advice and

additional explanations.

[ ] indicates direct function keys (e.g., [RANGE]).

< > indicates RPM4 screen displays (e.g., <1yes>).

Page VII

RPM4™ OPERATION AND MAINTENANCE MANUAL

NOTES

Page VIII

1. INTRODUCTION

1.1

PRODUCT OVERVIEW

RPM4 is a stand-alone, microprocessor driven, reference pressure monitor intended to precisely

measure gas or liquid pressure in a wide variety of pressure calibration, measurement and testing

applications. It has been designed to provide very high performance and extensive features combined

with maximum versatility and ease of use.

RPM4 uses one or two quartz reference pressure transducer (Q-RPT) modules and, in some cases a

barometer, to measure pressure.

RPM4 can be controlled locally by the operator using its front panel display and keypad or remotely by a

computer using ASCII character command strings transmitted over its standard RS232 or IEEE-488.2

interface.

RPM4 models are available in ranges from as low as - 3 to 3 kPa (0.4 psi) to as high as 280 MPa (40 000 psi)

in absolute, gauge, compound gauge and differential measurement modes.

RPM4 can be integrated into a PPC3 Pressure Controller/Calibrator System to serve the PPC3’s external

pressure measuring reference (see the PPC3 Operation and Maintenance Manual).

A special configuration of RPM4 designated RPM4-AD is available for air date (altitude and

airspeed) applications. The RPM4-AD model has its own specific manual p/n 550148.

Page 1

RPM4™ OPERATION AND MAINTENANCE MANUAL

1.2

SPECIFICATIONS

1.2.1

GENERAL SPECIFICATIONS

85 to 264 VAC, 50/60 Hz, 25 VA max consumption

and 12VDC, 1.2 A

Power Requirements

15 to 35 °C

Operating Temperature Range

Storage Temperature Range

Vibration

- 20 to 70 °C

Meets MIL-T-28800D

To prevent product overheating, provide proper ventilation. Allow 10 cm

(4 in.) clearance from rear panel cooling fan.

Ventilation

5 kg (11 lb) approx. (varies slightly with number and type of Q-RPT modules)

10 cm H x 22.7 cm W x 24 cm D (3.9 in. x 9.3 in. x 9.5 in.)

Motorola 68302, 16 MHz

Weight

Dimensions

Microprocessors

Communication Ports

Fuses

RS232 (COM1, COM2), IEEE-488.2

1 A, 250 VAC fuse, 5 x 20 mm, time lag type fuse

Internal power supply fuse not replaceable by operator: 2.5A, 250 VAC

One or two independent quartz reference pressure transducer (Q-RPT)

modules cover vacuum to 280 MPa (40 000 psi)

Pressure Ranges

Operating Medium

Any clean, dry, non-corrosive gas or liquid. Q-RPTs less than 7 MPa full scale,

gas only

Pressure Connections

Q-RPTs up to A70M

1/8 in. NPT F

Q-RPTs > A70M

DH500 F

TEST(+):

TEST(-):

1/8 in. NPT F

None

VENT or ATM:

10-32 UNF (VENT)

10-32 UNF (ATM)

DH500 is a gland and collar type fitting for 6mm (1/4 in.) coned and left

hand threaded tubes equivalent to AE F250C, HIP HF4, etc.

Included on all gas operated Q-RPT modules of A7M or lower. Isolates

Q-RPT module TEST(+) port and vents it to atmosphere. SDS is not included

with liquid filled Q-RPTs.

Maximum Working Pressure: 104 % Q-RPT maximum

Maximum Pressure Without Damage: 125 % Q-RPT maximum

Self Defense System (SDS™)

Pressure Limits

Maximum SDS Protection Pressure: 10 MPa (1 500 psi):

Without Damage: 13 MPa (2 000 psi)

Available, must be specified

CE Mark

1.2.2

PRESSURE MEASUREMENT SPECIFICATIONS

1.2.2.1

QUARTZ REFERENCE PRESSURE TRANSDUCER (Q-RPT)

RPM4 can be configured with one or two quartz reference pressure transducer (Q-RPT)

modules to measure pressure. The type (Axxx, Gxxx, BGxxx, BAxxx) and range of

the Q-RPT module(s) determines the RPM4 measurement specifications.

All Q-RPTs whose maximum pressure is over 200 kPa (30 psi) are of the absolute

pressure type (Axxx) using an evacuated, permanently sealed reference.

Axxx Q-RPTs can measure absolute, gauge and negative gauge pressure. Gauge

pressure with an Axxx Q-RPT is defined by offsetting atmospheric pressure and

applying dynamic compensation for atmospheric changes using the on-board

barometer (see Section 3.2.2). Gxxx (gauge) Q-RPTs can measure positive gauge

pressure only. BGxxx (bi-directional gauge) Q-RPTs can measure gauge and

negative gauge pressure. See Section 3.3.3 for additional information on

absolute, gauge and negative gauge measurement modes.

RPM4s configured with two Q-RPT modules have independent TEST ports and can

measure separately. Two Q-RPTs can also be used together to operate in

differential mode (see Section 3.3.3.1) and parallel mode (see Section 3.2.4).

Page 2

1. INTRODUCTION

Q-RPTs of A10M and lower are available with two different performance

levels, STANDARD class and PREMIUM class. See the product label on the

RPM4 rear panel, the Q-RPT module label on the rear panel and/or the

product calibration reports to determine the class of the Q-RPT(s) installed

in RPM4.

Table 1. Reference Pressure Transducer (Q-RPT) Module Designations and Ranges

SI VERSION

US VERSION

MAXIMUM

RANGE

[kPa]

MAXIMUM

RANGE

[psi]

MAXIMUM

RANGE

[psi]

MAXIMUM

RANGE

[kPa]

Q-RPT

DESIGNATION

Absolute

280 000

200 000

140 000

100 000

70 000

40 000

20 000

14 000

10 000

7 000

3 500

2 000

1 400

700

Gauge

280 000

200 000

140 000

100 000

70 000

40 000

20 000

14 000

10 000

7 000

3 500

2 000

1 400

700

Absolute

40 000

30 000

20 000

15 000

10 000

6 000

3 000

2 000

1 500

1 000

500

Gauge

40 000

30 000

20 000

15 000

10 000

6 000

3 000

2 000

1 500

1 000

500

A280M-L¹

A200M-L¹

A140M-L¹

A100M-L¹

A70M¹

A40M¹

A20M¹

A14M¹

A10M¹

A7M¹

A3.5M¹

A2M¹

300

A1.4M¹

A700K¹

A350K¹

A200K¹

A160K¹

A100K¹

BA100K⁴

G200K²

G100K²

G15K²

200

100

350

250

200

100

160

110

1.5

110

200

100

2.2

BG15K³

±15

± 2.2

1. All AXXXX RPTs support absolute, gauge and compound (negative) gauge modes.

2. All GXXXX RPTs are positive gauge mode only.

3. BG15K is bi-directional gauge from - 15 to + 15 kPa (- 2.2 to + 2.2 psi).

4. BA100K is a barometric range whose low point is 70 kPa absolute (10 psi).

Page 3

RPM4™ OPERATION AND MAINTENANCE MANUAL

30 minute temperature stabilization recommended from

cold power up.

Warm Up Time

To 1 ppm, user adjustable

5 to 35 °C

Resolution

Compensated Temperature Range

Acceleration Affect

± 0.008 % /g maximum, worst axis

Allows operation at ± 20° from reference plane without

significant effect

± 0.005% of reading

Predicted One Year Stability

(all classes and types)¹

Q-RPTs UP TO A10M (1500 psi)

STANDARD CLASS

PREMIUM CLASS

± 0.005% of reading, 0.0015%

of AutoRanged span, or

0.0005% of Q-RPT span,

whichever is greater ⁵

Precision²

± 0.008% of reading or

0.0024% of Q-RPT span,

whichever is greater ⁴

Measurement Uncertainty³

± 0.01% of reading or 0.0030%

of Q-RPT span, whichever is

greater ⁴

± 0.008 % of reading, 0.0024%

of AutoRanged span, or

0.0007% of Q-RPT span,

whichever is greater ⁵

Q-RPTs A14M TO A140M (2 000 to 20 000 psi)

Precision²

± 0.012% of reading or 0.0036% of Q-RPT span, whichever is

greater ⁴

Measurement Uncertainty³

± 0.013% of reading or 0.0039% of Q-RPT span, whichever is

greater ⁴

Q-RPTs A200M TO A280M (30 000 to 40 000 psi)

Precision²

± 0.015% of reading or 0.0045% of Q-RPT span, whichever is

greater ⁴

Measurement Uncertainty³

± 0.018% of reading or 0.0054% of Q-RPT span, whichever is

greater ⁴

1. Predicted Q-RPT measurement stability limit (k=2) over one year assuming regular use of AutoZero function. AutoZero

occurs automatically in gauge mode whenever vented, by comparison with barometric reference in absolute mode.

Absolute mode predicted one year stability without AutoZ is ± (0.005 % Q-RPT span + 0.005 % of reading).

2. Combined linearity, hysteresis, repeatability. Add + 1 Pa (0.00015 psi) in gauge mode with an Axxx (absolute) Q-RPT for

the resolution and short term stability of the on-board barometer.

3. Maximum deviation of the Q-RPT indication from the true value of applied pressure including precision, predicted one year

stability limit, temperature effect and calibration uncertainty, combined and expanded (k=2) following the ISO “Guide to the

Expression of Uncertainty in Measurement.”

4. % of reading value times measured pressure from 100 to 30 % of Q-RPT span. Under 30 % of Q-RPT span, % of reading

value times 30 % of Q-RPT span. For example, if the Q-RPT is a Standard A160K, the Measurement Uncertainty in

pressure is 0.010% times the measured pressure to 48 kPa (160 kPa span x 30%) and 0.0048 kPa (160 kPa span x 30%

x 0.01%) under 48 kPa.

5. % of reading value times measured pressure from 100 to 30 % of AutoRanged span. Under 30% of AutoRanged span, % of

reading value times 30% of AutoRanged span. If AutoRanged span is less then 30% of maximum Q-RPT span, % of reading

values times measured pressure, or % of reading times 9% of Q-RPT span, whichever is greater. For example, if the Q-RPT is a

Premium A160K and AutoRanged span is 160 kPa, the Measurement Uncertainty in pressure is measured pressure x 0.008% to

48 kPa (160 kPa AutoRanged span x 30%) and 0.0038 kPa (160 kPa span x 30% x 0.008%) under 48 kPa. If the AutoRanged

span is 100 kPa (greater than 30% of 160 kPa maximum Q-RPT span), the Measurement Uncertainty in pressure is measured

pressure x 0.008% to 30 kPa (100 kPa AutoRanged span x 30%) and 0.0025 kPa (100 kPa span x 30% x 0.008%) under 30 kPa.

If the AutoRanged span is 30 kPa (less than 30% of the 160 kPa maximum Q-RPT span), the Measurement Uncertainty in

pressure is measured pressure x 0.008% to 14.4 kPa (160 kPa maximum Q-RPT span x 9%) and 0.0012 kPa (160 kPa maximum

Q-RPT span x 9% x 0.008%) under 14.4 kPa.

1.2.2.2

ON-BOARD BAROMETER

The on-board barometer is used only to measure changes in atmospheric pressure

to provide dynamic compensation of the Q-RPT’s atmospheric pressure offset when

using an Axxx (absolute) Q-RPT to make gauge pressure measurements and for

line pressure compensation of G15K and BG15K Q-RPTs.

There is no on-board barometer in RPM4s that have Gxxx (gauge)

Q-RPTs only.

Page 4

1. INTRODUCTION

1.2.3

BATTERY AND CHARGER PACK

100 to 240 VAC, 50/60 Hz, 15 W max consumption

Power Requirements

0 to 50 °C

Operating Temperature Range

Storage Temperature Range

Vibration

- 20 to 50 °C

Meets MIL-T-28800D

2 kg (4.4 lb)

Weight

8 cm H x 22.5 cm W x 20 cm D (3.1 in. x 8.9 in. x 7.9 in.)

Dimensions

Nickel Metal-Hydride

12 VDC

Battery Type

Battery Voltage

Battery Capacity

Typical: 9000 mAh

Min: 8200 mAh

Full charge from empty, 14 to 16 hours approx.

8 to 12 hours

Charge Time

Approx. Run Time, Full Charge

Page 5

RPM4™ OPERATION AND MAINTENANCE MANUAL

NOTES

Page VI

2. INSTALLATION

2.1

UNPACKING AND INSPECTION

2.1.1

REMOVING FROM PACKAGING

RPM4 is delivered in a corrugated container with polyethylene inserts to hold it in place; or in

the optional molded, medium density polyethylene shipping case with a custom foam insert

for holding the RPM4.

Remove the RPM4 and its accessories from the shipping container and remove each

element from its protective plastic bag.

2.1.2

INSPECTING CONTENTS

Check that all items are present and have no visible damage.

A standard RPM4 includes all items indicated in Table 2.

Table 2. RPM4 Packing List

DESCRIPTION

PART #

FAM008

1 ea.

RPM4 Reference Pressure Monitor

Calibration Report

550100

ACCESSORIES:

401967 (401967-CE)

550129

1 ea.

Operation and Maintenance Manual

Power Cord (7.5 ft.)

100770 (100770-CE)

103303

Ferrite sleeve (snap on to COM2 cable for CE)

General Accessories Disk (white CD)

102987

OPTIONAL BATTERY/CHARGER PACK

401904 (401904-CE)

401980

1 ea.

Battery/charger pack

Battery/charger pack to RPM4 cable

Power Cord (7.5 ft.)

401979

100770 (100770-CE)

560062

Instruction Sheet

Page 7

RPM4™ OPERATION AND MAINTENANCE MANUAL

2.2

SITE REQUIREMENTS

Install RPM4 on a flat, stable surface at a convenient height. The front feet can be extended so that the

unit can be inclined for easier viewing. The RPM4 can also be mounted in a standard 19 in. rack mount

using the optional rack mount kit.

2.3

SETUP

2.3.1

PREPARING FOR OPERATION

To prepare RPM4 for check out and operation:

Remove the plastic caps from the RPM4 rear panel pressure connections.

Remove the protective plastic sheet from the front panel display.

Familiarize yourself briefly with the front and rear panels (see Section 2.3.2).

2.3.2

FRONT AND REAR PANELS

2.3.2.1

FRONT PANEL

1. Ready/Not Ready Indicator 4. Cursor Control Keys

2. Display

5. Multi-Function Keypad

3. Remote Activity Indicator

Figure 1. Front Panel

Page 8

2. INSTALLATION

2.3.2.2

REAR PANEL

1. 12VDC Power Supply

Connection

10. TEST(+) Pressure Port, Lo Q-RPT

(if Lo Q-RPT present)

11. TEST(-) Pressure Port, Lo Q-RPT

(if Lo-QRPT present, <A100M only)

12. TEST(+) Pressure Port, Hi Q-RPT

13. TEST(-) Pressure Port, Hi Q-RPT

(<A100M only)

2. Remote [ENT] Connector

3. IEEE-488 Connector

4. COM2 Connector

5. COM1 Connector

6. Power Switch

14. VENT (<A10M>) or ATM (>A10M)

Pressure Port, Lo Q-RPT

15. VENT or ATM Pressure Port, Hi Q-RPT

16. Product Label (bottom of case)

7. Fuse

8. Electrical Power Connector

(IEC-320-C13)

9. Fan

Figure 2. Rear Panel

2.3.3

POWER CONNECTION

2.3.3.1

85 TO 264 VAC, 50/60 HZ VAC POWER

Check that the RPM4 power switch is OFF.

Connect the supplied power cable to the rear panel power module.

Connect the other end of the power cable to an electrical supply of 85 to 264 VAC,

50/60 Hz.

2.3.3.2

BATTERY PACK

Charge the battery pack fully (see Section 3.2.6).

Connect the RPM4 12VDC power connection on the rear panel of the RPM4

to the 12 VDC power connection on the battery/charge pack using the cable

supplied with the pack.

See Section 3.2.6 for additional information on battery/charger pack

operation and maintenance.

Page 9

RPM4™ OPERATION AND MAINTENANCE MANUAL

2.3.4

REMOTE [ENT] CONNECTION (FOOTSWITCH OR OTHER

SWITCH)

Connect the optional remote ENTER footswitch, if available or a user supplied switch fitted to

the optional cable (see Section 7.1). Connect the cable to the RPM4 rear panel connection

labeled REMOTE ENTER. Activating the switch is equivalent to pressing the [ENT] key on

the front panel (see Section 3.1.3).

2.3.5

CONNECTING TO MEASURE PRESSURE (TEST(+) AND

TEST(-) PORTS)

Using a pressure connecting hose or tube of appropriate pressure rating, connect the device

or system to be tested to the RPM4 TEST(+) port.

The RPM4 TEST(+) connection is 1/8 in. NPT female (Q-RPTs of A70M or lower) or DH500 F

(Q-RPTs higher than A70M).

DH500 is a gland and collar type fittings for 6.35 mm (1/4 in.) coned and left hand

threaded tubes. DH500 is equivalent to AE F250C, HIP HF4, etc.

The TEST(+) and TEST(-) ports on Q-RPT modules of A70M and lower are threaded into

the aluminum Q-RPT manifold. Take care in making and breaking fittings not to cross

thread or otherwise damage the threads. It is recommended that an adaptor be

installed in the in Q-RPT manifold and make break operations be made on the adaptor

rather than the manifold.

SDS Self Defense System: Q-RPT modules designated A7M or lower include the SDS Self

Defense System. SDS, operated properly, allows a the Q-RPT TEST(+) port to be left

connected to a pressure up to 10 MPa (1 500 psi) without damage to the Q-RPT.

Do NOT attempt to use SDS in this manner without first becoming thoroughly familiar

with its operation and limitations (see Sections 3.2.7, 3.3.8, 3.5.4).

Q-RPT MODULE TEST(+) AND TEST(-) PORTS

Q-RPT modules of A70M and lower have both TEST(+) and TEST(-) ports. Q-RPT modules

greater than A70M have a TEST(+) port only. See Section 5.6, Figure 8 for RPM4 Q-RPT

module TEST port configurations.

The TEST(+) port is connected to Axxx (absolute) Q-RPTs’ sole measurement port and to the

high side of Gxxx or BGxxx (gauge or bi-directional gauge) Q-RPTs.

The TEST(-) port of Axxx and BGxxx Q-RPTs is connected to RPM4’s internal barometer.

The TEST(-) is connected to the low side of Gxxx (gauge) or Gxxx (bi-directional gauge)

Q-RPTs.

•

When operating in absolute mode: The TEST(-) port, if present, is left open to

atmosphere.

•

When operating in gauge or negative gauge mode with a range greater than 50 kPa

(7.5 psi): The TEST(-) port, if present, is normally left open to atmosphere. A possible

exception is when the device or system under test is in an ambient pressure that may differ

significantly from the ambient pressure around the RPM4. For example, if the RPM4 is

measuring the pressure applied to DUTs in an environmental chamber, the pressure in the

environmental chamber may be different from ambient pressure around the RPM4. In this

Page 10

2. INSTALLATION

case, connecting a tube from the TEST(-) port to the inside of the chamber may improve

measurement results. If the Q-RPT in use is an Axxx Q-RPT, this tube must be left open to

the environment so that the pressure inside cannot deviate too far from ambient. When using

an Axxx Q-RPT, if this tube is connected to the low or reference side of DUTs, be sure to

open it to the local environment as well.

•

When operating in gauge or negative gauge mode with a range less than 50 kPa

(7.5 psi): As a general rule, it is preferable to connect the RPM4 TEST(-) port(s) directly to

the low or reference side of the device under test to assure that these are at the same

pressure. When using an Axxx Q-RPT, this connection must also be open to atmosphere.

When using a Gxxx or BGxxx Q-RPT, it is preferable that this connection not be open to

atmosphere.

Do not connect a pressure supply to the TEST(-) port. The pressure applied to this port

should be maintained at atmospheric pressure (between 70 and 110 kPa (10 and 16 psia)).

Exceeding these limits may damage a Gxxx or BGxxx Q-RPT and/or the RPM4’s on-board

barometer.

Using the RPM4 with gas operated Q-RPTs connected to a system with liquid

contaminants without taking proper precautions to purge the system and test line may

cause contamination of the RPM4 that will require non-warranty service.

2.3.6

THE VENT OR ATM PORT

RPM4 Q-RPT modules of A7M and lower have a VENT port. The VENT port is connected to the

TEST(-) port when SDS is CLOSED (see Section 5.6, Figure 8). For Axxx and BGxxx Q-RPTs,

the RPM4 on-board barometer, is connected to the VENT port when SDS is CLOSED.

The VENT port should always be left completely unobstructed and open to atmosphere.

RPM4 Q-RPT modules of A10M and higher have an ATM port. The ATM port is connected

to the RPM4 on-board barometer. The ATM port should always be left completely unobstructed

and open to atmosphere.

NEVER plug, obstruct or connect a supply pressure to the RPM4 VENT or ATM port. This

may adversely affect GAUGE mode operation and AutoZeroing functions.

2.3.7

CHECK/SET SECURITY LEVEL

RPM4 has a security system based on user levels. By default, the security system is set to

“low”, which includes access restriction to internal calibration coefficients, and there is no

password required to change the security level. See Section 3.5.5.5 for information on the

security level system. As part of the RPM4 startup, determine the security level that is

appropriate for the RPM4 and set a password if desired.

RPM4 is delivered with the security level set to “low” to avoid inadvertent altering of critical

internal settings but with access to changing security levels unrestricted. It is recommended

that the low security level be maintained at all times and password protection be

implemented if control over setting of security levels is desired.

Page 11

RPM4™ OPERATION AND MAINTENANCE MANUAL

2.3.8

TURN OFF ABSOLUTE AND NEGATIVE GAUGE MODE

(AXXX RPT)

If your RPM4 has one or two Axxx (absolute) Q-RPTs, it is able to operate in

gauge, negative gauge and absolute measurement modes (see Section 3.3.3).

If the RPM4 will be used in gauge mode only, the other measurement modes can

be turned off so they are no longer accessible. Turning off modes that are not

needed can avoid confusion and/or accidental use of the wrong measurement mode.

See Section 5.2.5 for complete information on turning off absolute and negative

gauge measurement modes.

Turn off absolute and negative gauge mode if desired.

2.3.9

SDS FULL TIME OFF

Gas operated Q-RPT modules of A7M or less, include the SDS Self Defense

System (see Section 3.2.7) to shut off the Q-RPT from the TEST(+) port. If this

function is not desired, SDS can be turned full time off so that in regular

operation, SDS is not present. With SDS full time off, the SDS overpressure

protection is still active.

See Section 3.5.4.2 for instructions on turning SDS full time off if desired.

2.3.10 PARALLEL MEASUREMENT MODE

If your RPM4 has two Q-RPTs of the same type (Axxx, Gxxx, BGxxx), it supports

parallel measurement mode in which both RPTs are used simultaneously to

measure a common pressure, statistically reducing uncertainty in the

measurement. Parallel measurement creates a new Q-RPT, designated <HL>,

which is the combination of the Hi and Lo Q-RPTs. See Section 3.2.4 for

complete information on parallel measurement mode.

Turn on parallel measurement mode if desired.

2.4

POWER-UP AND VERIFICATION

2.4.1

SWITCH POWER ON

Actuate the power switch on the RPM4 rear panel (if a 12 VDC power supply is already connected

to the 12 VDC connection, RPM4 power is already on). Observe the front panel display as

RPM4 initializes, error checks and goes to the MAIN RUN screen (see Section 3.1.1).

RPM4 default power-up condition is Hi Q-RPT active, SDS closed if present.

If the RPM4 fails to reach the MAIN RUN screen, service is required. Record the sequence

of operations and displays observed.

If the RPM4 Q-RPT module is equipped with SDS, SDS is CLOSED at power up and the

TEST(+) port is shut off. This causes <SDS CLOSED> to be flash periodically in the main

run screen in place of the measured pressure value.

Page 12

2. INSTALLATION

2.4.2

CHECK PRESSURE MEASUREMENT OPERATION

2.4.2.1

CHECKING ABSOLUTE MODE PRESSURE MEASUREMENT

If the RPM4 has an Axxx (absolute) Q-RPT, check that it operates properly in

absolute mode.

Make sure that the TEST(+) port is vented to atmosphere.

Use the [RANGE] function key to select the Axxx (absolute) Q-RPT DF range

(see Section 3.3.1).

Press the [MODE] function key and select <absolute> mode (see Section 3.3.3).

Use [UNIT] to change the pressure unit if desired (see Section 3.3.2).

If SDS is CLOSED (<SDS CLOSED> flashes over the display of pressure on

the top line of the display), OPEN SDS. Press [SDS], <2yes> to OPEN SDS

(see Section 3.3.8).

Do NOT OPEN SDS with a pressure higher than the maximum pressure of the

Q-RPT applied to the TEST(+) port. Damage to the Q-RPT may result.

Observe the current value of atmospheric pressure. Check that the value agrees

with the local value of atmospheric pressure within measurement tolerances (see

Section 1.2.2.1) Repeat this process for both Axxx (absolute) Q-RPTs if there

are two in the RPM4. . If a Q-RPT does not agree within tolerance, it may need

to be AutoZeroed (see Section 3.3.9), calibrated (see Section 5.2)

or repaired.

2.4.2.2

CHECKING GAUGE MODE PRESSURE MEASUREMENT

Make sure that the TEST(+) port is open to atmosphere.

Press the [MODE] function key and select <gauge> mode. Use [UNIT] to change

the pressure unit if desired (see Section 3.3.2)..

If SDS is CLOSED (<SDS CLOSED> flashes over the display of pressure on the

top line of the display), OPEN SDS. Press [SDS], <2yes> to OPEN SDS.

Do NOT OPEN SDS with a pressure higher than the maximum pressure of the

Q-RPT applied to the TEST(+) port. Damage to the Q-RPT may result.

The value indicated should be near zero. It is normal for the Q-RPT to indicate

a value other than zero when vented when gauge mode is first entered or the

range is changed. Press [AutoZ]. This runs AutoZ to zero the Q-RPT reading

(see Section 3.3.9.1). Upon return to the main run screen, observe that the

indication of measured pressure has zeroed.

If the display fails to zero properly, RPM4 may need repair.

Page 13

RPM4™ OPERATION AND MAINTENANCE MANUAL

2.5

SHORT TERM STORAGE

The following is recommended for short term storage of RPM4:

Vent the RPM4 test port

Switch power OFF.

Page 14

3. OPERATION

3.1

USER INTERFACE

RPM4 is designed to offer a balance between simple, straight forward operation and the availability of a

wide variety of advanced functions with a high level of operator discretion. The local operator interface is

through a 2 x 20 character alphanumeric display, a function/data keypad, a cursor control pad and a

Ready/Not Ready indicator.

Remote communications are by RS232 (COM1) and IEEE-488. See Section 4 for information on remote

communication.

3.1.1

MAIN RUN SCREEN

The RPM4 MAIN RUN screen is its home display that is reached on power-up and from

which other functions and menus are accessed. It is the very top level of all menu structures.

The MAIN RUN screen is where RPM4 is left in normal operation. It displays the current

measured pressure as well as a variety of additional information if desired.

Figure 3 and its legend summarize the RPM4 MAIN RUN screen fields and their functions.

RPM4 has a screen saver function which causes the display to dim if no key is pressed for

10 minutes. Pressing a key restores full power to the display. The screen saver time can

be changed or screen saving can be completely suppressed (see Section 3.5.5.1).

Page 15

RPM4™ OPERATION AND MAINTENANCE MANUAL

PRESSURE1UNITM hzRR

DDISPLAYFUNCIONnn/nn

DISPLAY FIELD

NAME

PURPOSE

CONTENTS

SECTION

1. PRESSURE1 Measured

pressure

Displays pressure

measured by the

active Q-RPT

Numerical pressure value and sign. 1.2.2.1

Intermittently flashes <SDS

3.2.7

CLOSED> when the Q-RPT is shut

off from the TEST(+) port by SDS.

2. UNIT

Unit of

measure

Identifies unit of

measure in which

pressure values are

displayed

Pressure unit abbreviation

3.3.2

3. M

4. h

Measurement Identifies

3.3.3

3.3.7

<a>

<g>

<d>

absolute

gauge or negative gauge

differential

mode

measurement mode

of displayed pressure

Head

pressure

indicator

Indicates whether a

fluid head correction

is applied to

<h>

the fluid head is not zero

<blank> fluid head is zero

PRESSURE1

5. z

AutoZero

indicator

Indicates whether

the AutoZero function

is ON or OFF for the

active Q-RPT and

measurement mode

3.5.1

3.2.3

<z>

AutoZ is ON

<blank> AutoZ is OFF

6. RR

Active

Indicates the position

of the active Q-RPT

in the RPM4

<Hi> Hi Q-RPT

<Lo> Lo Q-RPT

Q-RPT

position

indicator

<HL> Hi and Lo Q-RPTs together in

parallel measurement mode

<Hd> Hi and Lo Q-RPTs together in

differential measurement

mode

7. nn/nn

Sequence

progress

indicator

Indicates progress of

ATest sequence,

during test execution

3.3.10

3.3.6

<NN/NN> Number of this point

over total number of points

in the sequence

8. DISPLAY

FUNCTION

Information

specific to

Pressure indication

depending on current

Numerical pressure value

and sign.

the DISPLAY RPM4 DISPLAY

<PPC3 EXT DEV:> when the RPM4

is initialized as an external device

to a PPC3 pressure controller.

mode

function. Leading

character identifies

the value

9. D

Pressure

information

indicator

Pressure information

indicator depending

on current RPM4

3.3.6

<σ> Display mode is AVERAGE

and value is standard deviation

<R> Display mode is RATE and

value is pressure rate of

DISPLAY function.

change per second

<H> Display mode is HI/LO and

value is high, then low

<D> Display mode is DEVIATION

and value is difference from

current target

<Σ^,↑ ^,↓ > Display mode is RPT

and value is measurement

of inactive RPT

<F> Display mode is FREEZE and

value is last captured reading

Blank, no character Current

display mode is CLEAN

Figure 3. MAIN RUN Screen Display Fields

Page 16

3. OPERATION

3.1.2

FUNCTION / DATA KEYPAD LAYOUT AND PROTOCOL

The RPM4 has a function/data keypad for local operator access to direct

functions, function menus and for data entry.

1. The Function/Data keys allow very commonly 3. The Menu/Data keys provide access to

used functions to be accessed directly by a

single keystroke when pressed from the

MAIN RUN screen (see Section 3.1.1).

The name of the function is on the bottom

half of the key. These keys enter numerical

values when editing.

function menus when pressed from the

MAIN RUN screen. The menu name is on

the bottom half of the key. The SETUP

menu is for more frequently used functions

(see Section 3.4). The SPECIAL menu is for

functions that are not generally used as a part

of day to day operation (see Section 3.5).

These keys enter numerical values when editing.

2. The Editing and Execution keys are for

starting and suspending command execution,

cursor control in menus and editing entries.

Figure 4. Keypad Layout

Pressing the [ENT] key generally causes execution or forward movement in the

menu tree.

Pressing the [ESC] key moves back in the menu tree and/or causes execution to

cease or suspend. Pressing [ESC] repeatedly eventually returns to the MAIN RUN

screen and, from there, allows momentary viewing of the RPM4 introduction

screen.

Pressing the [+/-] key changes a numerical sign when editing. It also toggles

through multiple screens when available and, from some run screens, is a

shortcut to a momentary display of active RANGE.

Pressing the [ ], [ ], [ ] and [ ] keys allows up, down, reverse and

forward cursor movement when editing data entry or moving in menus.

Some screens go beyond the two lines provided by the display. This is

indicated by a flashing arrow in the second line of the display. Press the

cursor control keys to move the cursor to access the lines that are not

visible or directly enter the number of the hidden menu choice if you know it.

Page 17

RPM4™ OPERATION AND MAINTENANCE MANUAL

3.1.3

REMOTE [ENT] (ENTER) FOOTSWITCH

The optional remote ENTER function is a switch that duplicates the function of the front panel

[ENT] key. The remote ENTER function is serviced by a connector on the RPM4 rear panel.

An optional footswitch is available to activate remote entry hands free or a different switch

may be used. See Section 7.1 for information on remote ENTER switch wiring.

The remote ENTER feature can be particularly convenient when running AutoTests

(see Section 3.3.10) in which using a footswitch to [ENT] allows hands free operation. It can

also be used, with the FREEZE display function (see Section 3.3.6.6) to capture the

activation point of a pressure switch.

3.1.4

SOUNDS

RPM4 is equipped with a variable frequency tone device to provide audible feedback and

alarms. The beeper is used for the following indications.

Brief beep. Choice between three frequencies or NO

sound is available (see Section 3.5.5.2).

Valid key press

Descending two tone “blurp”

Invalid key press

Three two second beeps (see Section 3.3.5).

Intermittent one second beeps (see Section 3.4.4).

Eight second high frequency beep (see Section 3.4.4.1).

Leak check completed

Upper or lower limit exceeded

Pmax! (overpressure limit)

exceeded

Rapid beeps for 8 seconds (3.2.4).

Parallel measurement mode

possible disconnection of the

Hi and Lo Q-RPTs

Ascending triad/descending triad (see Section 3.3.10).

AutoTest in/out of tolerance

reading

3.2

GENERAL OPERATING PRINCIPLES

3.2.1

PRESSURE READY/NOT READY

There is a Ready/Not Ready indication LED on the RPM4 front panel. This indication is

intended to provide the user with a clear and objective indication of when a stable pressure

has been achieved. Ready is indicated when the current stability (rate of change) of

pressure is less than the stability limit. The user can set the stability limit (see Section 3.4.3).

The ready indication is often used when comparing the RPM4 and a test device to indicate

when a valid reading can be made.

In RPM4s with two Q-RPTs, the Ready/Not Ready indication always applies to the active

Q-RPT, whose pressure measurement is displayed on the top line of the RPM4 display.

When the inactive Q-RPT measurement is displayed on the second line using the RPT

display mode, the Ready/Not Ready indication for the inactive RPT is indicated by the

leading character on the line. <Σ> indicates Ready. < > or < > indicate Not Ready,

↓

↑

pressure increasing or pressure decreasing.

The Ready/Not Ready LED indications are:

<Green > Pressure Ready

<Red> Pressure Not Ready

The pressure stability is within the stability limit.

The pressure stability is NOT within the stability limit.

Page 18

3. OPERATION

In differential measurement mode (see Section 3.3.3.1), the LED Ready/Not Ready

indication applies to the differential pressures.

In parallel measurement mode (see Section 3.2.4), the LED Ready/Not Ready indication

applies to the average pressure read by the <HL> Q-RPT.

When RPM4 is being used as an external measurement reference of a PPC3 pressure

controller, the Ready/Not Ready indication is still based on the RPM4 stability and

stability limit only. The RPM4’s Ready/Not Ready LED does not indicate whether the

PPC3 pressure control is Ready.

3.2.2

GAUGE AND NEGATIVE GAUGE MODES WITH AN AXXX

(ABSOLUTE) Q-RPT, DYNAMIC COMPENSATION FOR

ATMOSPHERIC PRESSURE

Q-RPTs with the designation Axxx are intrinsically absolute but they are also used for gauge and

negative gauge measurement modes (see Section 3.3.3, PRINCIPLE). Gauge measurement

modes are achieved by subtracting the value of atmospheric pressure, P_offset,G, from the

Q-RPT’s absolute reading using AutoZ (see Section 3.2.2). The AutoZ routine that measures

P_offset,G, is run by pressing [AutoZ] whenever RPM4 is in the vented condition. This assures

the continuous updating of the P_offset,Gvalue corresponding to atmospheric pressure. Gauge

pressure is the measured absolute pressure, P_u, minus the atmospheric offset.

P_gauge= P_u- P_offset,G

However, atmospheric pressure may change between opportunities to run AutoZ and update

the value of P_offset,G, for example when running an extended test without venting. RPM4 uses

dynamic compensation for atmospheric pressure to correct for changes in atmospheric

pressure between opportunities to run AutoZ and update P_offset,G. When AutoZ runs, and

P_offset,Gis determined, the reading of RPM4’s on board barometer, P_atm,0, is also recorded.

Later, when no longer vented, the change in atmospheric pressure, ΔP_atm, since P_offset,Gwas

updated, is the difference between the current barometer reading, P_atm, and the barometer

reading at the time of AutoZ execution, P_atm,0

ΔP_atm= P_atm- P_atm,0

Dynamic compensation for atmospheric pressure uses ΔP_atmto correct the value of P_offset,G

thus always compensating real time for changes in atmospheric pressure:

P_gauge= P_u- P_offset,G- ΔP_atm

Gauge pressure measurement on an Axxx (absolute) Q-RPT allows instantaneous switching

between gauge and absolute measurements modes. The additional uncertainty in gauge

pressure mode due to the dynamic compensation for atmospheric pressure technique is a

function of the resolution and short term stability of the on-board barometer, not its absolute

measurement uncertainty. This additional uncertainty is ± 1 Pa (0.00015 psi).

3.2.3

MULTIPE RANGES (Q-RPTS, AUTORANGE AND INFINITE

RANGING)

An RPM4 may have one or two Q-RPTs. Position indication of the currently active Q-RPT is

continuously displayed in the upper right hand corner of the MAIN RUN screen and most other

screens. See Table 3 for position designation protocol for the Q-RPTs in an RPM4.

See Table 1 for a complete listing of RPM4/RPM4 Q-RPT choices and their default ranges.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

Table 3. Position Designators of Q-RPTs in an RPM4 System

Q-RPT POSITION

DISPLAY SYMBOL*

Q-RPT with highest maximum pressure,

installed in HIGH RPT position

Q-RPT with lower maximum pressure in

dual Q-RPT RPM4, installed in LOW

RPT position.

Two Q-RPTs being used simultaneously

in parallel measurement mode

Hi Q-RPT when used in differential

measurement mode

The display symbol is included in the upper, right hand corner of most RPM4

menu displays as a convenient indicator of the active Q-RPT.

An RPM4 may have multiple ranges. Each RPM4 Q-RPT has a default range which is its

maximum span. Additional ranges, lower than the Q-RPT’s maximum span, may also be

created using AutoRange (see Section 3.3.4). Ranges created using are AutoRange

temporary but may be saved with all their settings for reactivation (see Section 3.4.1).

AN RPM4 range is identified by a range screen showing the Q-RPT used by the range, its current unit

of measure and its full scale pressure in gauge and absolute (if available) measurement modes.

The range screen is:

1. Q-RPT designator.

2. Type of range. DF for the Q-RPT’s default range; AR for a range

created by AutoRange.

Active A700K DF Hi

psi 100g/100a

3. Q-RPT position designator.

4. Current pressure unit of measure.

5. Full scale pressure in current unit of measure in gauge (<g>) and/or absolute

(<a>) measurement mode depending on type of Q-RPT and range.

The ranges available on an RPM4 system are accessed using [RANGE] (see Section 3.3.1)

and/or created using [AutoRange] (see Section 3.3.4).

Most settings made in an RPM4 range, such as unit of measure, measurement mode, display

resolution, and stability setting are specific to the range. Settings selected while one range is

active apply to that range and not to other ranges. The range specific settings are stored with

the range and recalled whenever the range is made active. This makes setting up ranges a

convenient way to store and recall frequently used operating configurations. See Table 4 for a listing

of RPM4 adjustments and settings and whether they are range, Q-RPT or system specific.

Page 20

3. OPERATION

Table 4. Settings and What They Are Specific To

(Range, Measurement Mode, Q-RPT, System)

SETTING

[Unit]

PURPOSE

SPECIFIC TO

SECTION

3.3.2

Set pressure unit of measure

Range

[Mode]

Set pressure measurement mode (absolute,

gauge, negative gauge)

3.3.3

[Display]

[Head]

Set bottom line display function

System

3.3.6

3.3.7

Set fluid head correction height, fluid, unit of

measure

[SDS]

Open and close SDS

Q-RPT

3.3.8

[AutoZ]

Run AutoZ

Q-RPT and measurement mode

Range

3.3.9

3.4.2

3.4.3

3.4.4

3.5.1

3.5.5

Resolution

Stability

Upper Limit

AutoZ

Set pressure display resolution

Set Ready/Not Ready stability test.

Set upper and lower pressure limit alarm

AutoZ, ON/OFF, set and view values

Set system user preferences

Range

Range and measurement mode

Q-RPT and measurement mode

System

Screen Saver,

Sound, Time,

ID, Level

Lo vnt

Cal

Q-RPT

3.5.7.4

3.5.8

Set status of TEST(-) vent valve, if present

Various Q-RPT and barometer calibration

functions, including turning off absolute and

negative gauge modes

Q-RPT or barometer

3.2.4

PARALLEL MEASUREMENT MODE

RPM4s equipped with two Q-RPT modules of the same type (Axxx, Gxxx, BGxxx) can be set

to operate in parallel measurement mode.

Parallel measurement mode is intended to improve measurement reliability and reduce measurement

uncertainty by using the measurements of two Q-RPTs together. In parallel measurement

mode, the measured pressure is the average of the readings of the two Q-RPTs.

Parallel measurement mode is considered a third Q-RPT designated <HL> (combination of

Hi and Lo). Once it has been set up, the HL Q-RPT can be selected using the [RANGE] key

and operated with all the features of a Hi or Lo Q-RPT. When setting up parallel measurement,

the Hi and Lo Q-RPTs can be suppressed so that only the HL Q-RPT is active. This feature is

used when the RPM4 will always be used in HL mode.

Parallel measurement mode is set up using [SPECIAL], <7internal>, <3RPT2x>

(see Section 3.5.7.3).

3.2.5

USING RPM4 WITH A PPC3 CONTROLLER/CALIBRATOR

RPM4 can be integrated as a reference pressure measuring device in a PPC3 Pressure

Controller/Calibrator System. See the PPC3 Operation and Maintenance Manual for

information on setting up RPM4 to operate as the PPC3’s external device.

Before an RPM4 is used with a PPC3, the following settings should be made:

SDS

Close SDS on all Q-RPT modules on which SDS is available (see Section 3.2.7).

Head

If the RPM4 TEST port is at a different level than the PPC3’s TEST port AND the

RPM4 will be used in absolute measurement mode, set the RPM4 head height to

the PPC3’s TEST port level so that RPM4 is corrected to indicate the pressure at

the level of the PPC3 TEST port (see Section 3.3.7).

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RPM4™ OPERATION AND MAINTENANCE MANUAL

AutoZ

Make sure AutoZ is ON for all RPTs and measurement modes (see Section 3.5.1).

Certain RPM4 settings may be changed when an RPM4 is operated with a PPC3. Settings

that may be changed when an RPM4 is used as a PPC3 external device include:

SDS

Closed or open status may be changed and SDS full time off will be

overwritten to full time on (see Sections 3.3.8, 3.5.4)

AutoRange range

Display

May be rewritten (see Section 3.3.4).

When an RPM4 is initialized by PPC3 as an external device, the

second line of the RPM4 display is <PPC3 EXT DEV: IDLE>. When

the RPM4 is the active Q-RPT being used by the PPC3, the second

line of the RPM4 display is <PPC3 EXT DEV: ACTIVE>

Range

Active range may be changed (see Section 3.3.1).

Active unit may be changed (see Section 3.3.2).

Unit of measure

Measurement mode Active mode may be changed (see Section 3.3.3).

Lo Vent

Setting may be changed (see Section 3.5.7.4).

Communications

For a PPC3 to be able to identify and communicate with an RPM4,

the RPM4’s COM1 port must be set to:

Baud rate 9200 to 19200

Parity

Even

Data bits

Stop bit

When RPM4 is activated by a a PPC3, the PPC3 sets the RPM4

COM1 port baud rate to 19200. The COM1 port keeps this setting

until power is cycled. Cycling power restores the previous baud rate

setting. The same is true for the COM2 of the first RPM4 in a chain

of two RPM4s used with a PPC3.

When RPM4 is initialized as an external device to a PPC3 pressure controller, the RPM4

front panel keypad is locked out and the second line of the display becomes:

(if RPM4 is initialized by PPC3 but not currently in use)

<PPC3 EXT DEV: ACTIVE> (if RPM4 is initialized by PPC3 and is currently in use)

After using an RPM4 as an external device for a PPC3, cycle power to return to the

previous RPM4 settings, restore front keypad capability and return to the normal main

run screen.

Page 22

3. OPERATION

3.2.6

USE OF THE 12VDC BATTERY/CHARGER PACK

An optional 12VDC battery/charger pack is available to supply power to RPM4s 12VDC

power connection (see 1.2.3).

The battery/charger pack combines the battery and the battery charger.

To Charge the Battery

The battery may be charged while the battery/charge pack is connected to the RPM4.

To charge the battery, connect the battery/charger pack to a 100 to 240 V, 50/60 Hz power

supply using the supplied power cable and turn on the charger power switch. The green

CHARGE indicator light goes on to indicate that battery charging is in progress. Allow 14 to

16 hours for the battery to charge fully. When the battery is fully charged, the CHARGE

indicator light flashes.

When the battery charger power switch is in the ON, the battery is connected to the charger,

not the 12VDC output. When the battery charger switch is in the OFF position, the CHARGE

indicator light goes off, and 12VDC is supplied on the 12VDC connection.

To Use the Battery/Charger Pack to Supply RPM4

After charging the battery, connect the 12VDC connection of the battery/charger pack to the

12VDC connection on the RPM4 rear panel.

Turn the battery/charger pack power switch to OFF (when AC power is connected to the

battery/charger pack, the power switch must be OFF for 12VDC power to be output).

When RPM4 is connected to both a 12 VDC source and an AC source,if the RPM4 power

switch is OFF, the 12VDC source supplies the RPM4; if the RPM4 power switch is ON, the

12 VDC source is disconnected and the AC source supplies the RPM4.

To Check the Battery Charge Level

To check the current charge level of the battery, press the toggle switch on the

battery/charger pack front panel. Observe the BATTERY CHECK indicator lights. All three

lights are lit when battery is fully charged. If no light or one light is on, the battery should be

recharged.

Figure 5. Battery Pack/Charger

Page 23

RPM4™ OPERATION AND MAINTENANCE MANUAL

3.2.7

SDS SELF DEFENSE SYSTEM

Q-RPT modules designated 7M or lower that are NOT liquid filled are equipped with the SDS self

defense system. The SDS system includes hardware and embedded software to isolate Q-RPTs

from overpressure. When SDS is CLOSED for a Q-RPT module, the Q-RPT is isolated from the

modules TEST(+) port and opened to the modules VENT port (See Section 5.6, Figure 8).

SDS can be OPENED and CLOSED from the front panel using [SDS]. SDS can also be

controlled using functions under [SPECIAL], <4SDS>. The SDS “temp open/close” function

allows SDS on both Q-RPTs, whether active or inactive, to be opened and closed directly

(see Section 3.5.4.1). The SDS “full time on/off” function allows SDS to be opened permanently

so the RPM4 can be operated as if SDS were not installed (see Section 3.5.4.2).

SDS is normally used to isolate an RPM4 Q-RPT from a test system which may sometimes

be subjected to pressures higher than the Q-RPTs maximum pressure. When configuring a

multi-range system, this can eliminate the need for external valving or connecting and

disconnecting RPM4s. For example, two Q-RPTs of different ranges might be connected to

a single calibration system. When the Hi Q-RPT is in use, SDS is closed on the Lo Q-RPT to

protect it from overpressure. When used in this manner, SDS should be CLOSED prior to

applying pressure. Automatic SDS closing in response to overpressure should only be used in

an emergency overpressure situation.

SDS also attempts to protect Q-RPTs from accidental overpressure. Whenever RPM4 is

powered ON it continuously monitors the pressure read by its Q-RPT(s). If the pressure

reaches the maximum pressure limit for a Q-RPT, SDS CLOSES to isolate the Q-RPT from

the TEST port and vent it to atmosphere (see Section 3.4.4.1). This is not a fail safe

overpressure system. It does not protect against very rapid overpressure or pressure

exceeding 10 MPa (1 500 psi).

When an RPM4 is used as an external device to a PPC3 pressure controller, PPC3 controls the

RPM4’s SDS to isolate the RPM4 Q-RPTs from the test pressure when they are not in use.

IF the RPM4 SDS is “full time off” PPC3 changes it to “ON”.

The maximum pressure that should be applied to an RPM4 TEST(+) port when SDS is

CLOSED is 10 MPa (1 500 psi).

Though the SDS self defense system includes features to automatically protect Q-RPTs

against accidental overpressure, SDS should NOT be considered a fail-safe overpressure

protection system. SDS cannot guarantee that overpressure damage will NOT occur.

Conventional measures for overpressure protection should also always be used. Damage

to Q-RPTs due to overpressure is NOT covered by the RPM4 product warranty even when

SDS is present and ON.

Page 24

3. OPERATION

3.2.8

DIRECT FUNCTION KEYS SUMMARY

Table 5 provides a brief summary of direct function key operation. It may be useful to keep

a copy of this summary near the RPM4, especially when first becoming acquainted with

its operation.

Local operation of RPM4 is through the front panel keypad. To minimize multi-layered menu

structures, the keypad numerical keys also provide direct access to the most commonly used

functions. The function accessed is labeled on the bottom half of the key. Direct function

keys are active whenever RPM4 is in its MAIN RUN screen. Table 5 summarizes the

operation of the direct function keys.

Table 5. Summary of RPM4 Function Key Operation

DIRECT FUNCTION KEYS ARE ACTIVE FROM THE MAIN RUN SCREEN

See corresponding manual sections for full detail.

Adjust height of fluid head

correction. Set to zero to defeat

correction.

View active range and toggle

through available ranges. [ENT] on

a range activates it.

.SDS controls the connection of

the Q-RPT to the TEST(+) port.

Close any open SDS. Open SDS

of active Q-RPT if closed.

Select pressure unit of measure for

the active range. Choice of units

available in this menu can be

customized.

Run the AutoZ function to

AutoZero the active Q-RPT and

measurement mode.

Select the pressure measurement

mode for the active range (absolute,

gauge, negative gauge, differential).

Set up and optimize RPM4

features for a specific operating

range and measurement mode.

Menu of less commonly used internal

functions and settings.

Menu of commonly used setup

features

including

save/delete

Run automated leak checking

routine.

AutoRange ranges, set display

resolution, set stability limit, set

upper/lower, view AutoTest data

Start or set functions such as Leak

Check, AutoTest and Freeze.

ENTER values when editing.

Select the display function for the

bottom line of the RPM4 display.

3.3

DIRECT FUNCTION KEYS

3.3.1

[RANGE]

PURPOSE

To view and/or change the active pressure measurement range and associated settings.

PRINCIPLE

An RPM4 range is defined as a pressure span and associated settings (see Section 3.2.3).

An RPM4 may have multiple ranges. Each Q-RPT in the RPM4 system has a default range

which is its maximum span. Additional ranges, lower than the Q-RPT’s maximum span, may

also be created using AutoRange (see Section 3.3.4). Ranges created using AutoRange

may be saved, with their settings, for reactivation (see Section 3.4.1).

The [RANGE] function key allows the available RPM4 pressure ranges to be viewed and selected.

Page 25

RPM4™ OPERATION AND MAINTENANCE MANUAL

OPERATION

Pressing the [RANGE] function key activates the range viewing and selecting function.

When the [RANGE] function key is first pressed, the active range is displayed. For example:

1. Q-RPT designator.

2. Type of range. DF for the Q-RPT’s default range; AR for a range

created by AutoRange.

Active A700K DF Hi

psi 100g/100a

3. Q-RPT position designator.

4. Current pressure unit of measure.

5. Full scale pressure in current unit of measure in gauge and/or

absolute measurement mode depending on type of Q-RPT and range.

Pressing the [+/-] key or the [RANGE] key again while in the RANGE functions toggles

through displays of the other available ranges, from lowest range to highest range.

To select a range to become the active range, press [ENT] while the range is displayed.

Pressing [ESC] while in the RANGE function returns to the MAIN RUN screen without

making a range change.

Range full scale limits are given in the pressure unit that is currently active for that range.

Pressing [+/-] from the MAIN RUN screen provides a shortcut to a momentary view of the

active range.

Many RPM4 settings and functions are range specific. See Table 4 for identification of

range specific settings.

For best metrological performance, vent the RPM4 Q-RPT before changing ranges.

3.3.2

[UNIT]

PURPOSE

To select the unit of measure in which RPM4 displays pressure values.

For information on selecting the measurement mode (absolute, gauge, negative gauge,

differential), see Section 3.3.3.

PRINCIPLE

RPM4 allows the unit of measure in which pressure values are displayed to be changed.

RPM4 supports 15 standard pressure units of measure as well as user defined units.

To simplify operation, quick access to six units is made available under the [UNIT] key.

The default units available depend on whether the RPM4 was originally configured as an SI

or US version. The [UNIT] key contents can be customized by the user to any configuration

of six units (see Section 3.5.6).

Page 26

3. OPERATION

Internally, RPM4 always operates in Pascal (Pa), the SI unit of pressure. Values of pressure

are represented in other units by the application of conversion factors to convert from Pa

(see Section 7.2.1).

OPERATION

To change the active pressure unit of measure for a

range, press [UNIT] from the MAIN RUN screen while

the range is active. The display is:

1kPa 2Pa 3MPa

4hPa 5bar 6mbar

The cursor is on the number corresponding to the active pressure unit of measure for the active range.

To change the pressure unit of measure, select the desired unit. Making the selection

returns to the MAIN RUN screen with the selected unit active.

The pressure unit of measure selected is range specific. When in a given range, all functions

and settings are represented in the current measurement unit for that range. However,

certain internal and/or metrological functions (e.g., Q-RPT calibration coefficients) are always

represented in Pa regardless of the current range unit. When the current unit is an altitude

unit, the range and upper limit indications are in kPa if the unit is meters (m) and psi if

the unit is feet (ft).

See Section 7.2.1 for tables of the conversion factors used by RPM4.

If the pressure unit selected is inWa (inches of water), the reference temperature for water

density must we specified in a separate menu (choices are 4ºC, 20ºC 60ºF). No reference

temperature selection is necessary for the unit mmWa as the only reference temperature

commonly used for mmWa is 4 ºC.

The default pressure units of measure available under the UNIT function depend on whether

the RPM4 has been set up as an SI or US version (indicated by SI or US at bottom right of

introduction screen). The choice of six units available under the UNIT function can be

customized from a wider selection by the user (see Section 3.5.6). The units available under

the UNIT function can be reset to default by reset (see Section 3.5.9.2).

3.3.3

[MODE]

PURPOSE

To set the measurement mode (absolute, gauge, negative gauge or differential) for the active range.

For information on selecting the unit of measure, see Section 3.3.2.

PRINCIPLE

RPM4 supports simple, one-step switching between up to four different measurement modes:

Absolute

Measures pressure relative to vacuum (zero is hard vacuum). Range is

from zero absolute to full scale.

Page 27

RPM4™ OPERATION AND MAINTENANCE MANUAL

Gauge

Measures pressure relative to atmosphere (zero is ambient pressure).

Range is from zero gauge to full scale, full scale must be greater than zero.

Negative Gauge Measures pressure relative to atmosphere (zero is ambient pressure).

Range is positive and negative from zero, negative to minus one

atmosphere and positive to full scale. With a BGxxx RPT, negative range

is the negative equivalent of the positive range.

Differential

Available only for the Hi Q-RPT in RPM4s equipped with two Q-RPT modules

of the same type (Axxx, Gxxx, BGxxx). Measures the difference between the

Hi and the Lo Q-RPT (Differential = Hi – Lo). Differential measurement mode

is selected “on top of” the Hi Q-RPT’s base measurement mode (gauge,

absolute or differential). Differential range is positive to maximum pressure of

the Hi Q-RPT and negative to the minimum pressure of the Lo Q-RPT base

measurement mode (see Section 3.3.3.1 for specific information on operation

in differential measurement mode).

Which measurement modes are available depends on the type of Q-RPT type(s) available.

There are three types of Q-RPTs:

Axxx

Q-RPTs with designators starting with “A” measure pressure relative to a sealed

vacuum reference and are intrinsically absolute. Axxx Q-RPTs support

measurement in absolute, gauge and negative gauge modes. Gauge and negative

gauge modes are accomplished by offsetting of atmospheric pressure with

dynamic compensation for atmospheric pressure changes between offsets using

an on-board barometer (see Section 3.2.2). Access to absolute and negative

gauge operation can be turned OFF (see Section 5.2.5). In RPM4s with two Axxx

Q-RPTs, differential measurement mode is supported on the Hi Q-RPT.

Gxxx

Q-RPTs with designators starting with “G” measure positive pressure relative to the

TEST(-) port that is connected to atmosphere. Gxxx Q-RPTs support measurement

in gauge mode only. In RPM4s with two Gxxx Q-RPTs, differential measurement

mode is supported on the Hi Q-RPT.

BGxxx Q-RPTs with designators starting with “BG” measure positive and negative

pressure relative to the TEST(-) port that is connected to atmosphere. BGxxx Q-RPTs

support measurement in gauge and negative gauge modes. In RPM4s with two

BGxxx Q-RPTs, differential measurement mode is supported on the Hi Q-RPT.

When changing modes for a range, if the full scale of the range is 700 kPa (100 psi) or

greater, the full scale is the same in both absolute and gauge modes. If the full scale is less

than 700 kPa (100 psi), the gauge mode full scale is 100 kPa (14.5 psi) lower than the

absolute mode full scale. If the absolute mode full scale is less than 100 kPa (14.5 psi), there

is no gauge mode available. Gauge and negative gauge modes, when available, always

have the same full scale.

Measurement mode selection is range specific.

OPERATION

See Section 3.3.3.1 for information on differential mode operation. Differential mode

operation is only available for the Hi Q-RPT in RPM4s that are equipped with two Q-RPTs

of the same type (Axxx, Gxxx, BGxxx).

To change the active measurement mode for a range,

Measurement mode:

press [MODE] from the MAIN RUN screen while the

range is active. The display depends upon the type of

Q-RPT that is active.

1abs 2gage 3neg gage

Page 28

3. OPERATION

If an Axxx Q-RPT is active, all thee measurement modes are supported: absolute, gauge

and negative gauge. Only gauge is available if absolute and negative gauge modes have

been turned OFF in calibration (see Section 5.2.5).

If a Gxxx Q-RPT is active, only gauge measurement mode is supported. When the [MODE]

key is pressed, <Gauge RPT, gauge mode only> is displayed.

If the Hi Q-RPT is active in its default range (<DF>), and the RPM4 has two Q-RPTs of the

same type (Axxx, Gxxx, BGxxx), differential measurement mode is available in addition to the

other modes (see Section 3.3.3.1).

Certain RPM4 settings, including AutoZ ON/OFF (see Section 3.5.1) are range AND measurement

mode specific. See Table 4 for a listing of settings and what they are specific to.

Absolute and negative gauge modes on an Axxx Q-RPT can be turned OFF in the

calibration function (see Section 5.2.5). When absolute and negative gauge mode are

turned OFF for an Axxx Q-RPT, only gauge mode can be activated. <Gauge mode only,

other modes OFF> is displayed when [MODE] is pressed.

3.3.3.1

DIFFERENTIAL MEASUREMENT MODE OPERATION

Differential mode operation is only available on the Hi Q-RPT, default

(<DF>) range, in RPM4s that are equipped with two Q-RPTs (Hi and Lo) of

the same type (Axxx, Gxxx, BGxxx).

To activate differential measurement mode, press [MODE] from the MAIN RUN

screen while the Hi Q-RPT is active and in its default (<DF>) range. The actual

display depends upon the measurement modes available on the Hi Q-RPT.

The cursor is on the base measurement

mode. The line pressure measurement mode

is the base pressure measurement mode.

Meas mode: 1abs

2gage 3neg gage 4dif

To activate differential measurement mode, press the keypad number key for the

<dif> selection or move the cursor to the <dif> selection and press [ENT].

Operation returns to the main run screen. When differential mode is active,

the cursor is on both the base mode and differential mode.

When differential mode is active, the Q-RPT position indicator is in the upper

right hand corner of the main run screen and other displays is <Hd> instead

of <Hi> (see Section 3.2.3, Table 3).

When differential mode is activated, AutoZ should be run at the line pressure

with zero differential pressure applied to eliminate the zero error on differential

pressure due to the disagreement of the Hi and Lo Q-RPTs (see Section 3.3.9.3).

Page 29

RPM4™ OPERATION AND MAINTENANCE MANUAL

The following operating conditions are specific to differential mode:

Main run screen measured pressure display

The display of measured pressure in the main run

screen is the difference between the Hi and the Lo

Q-RPTs (Hi – Lo) with a differential mode AutoZ

correction (see Section 3.3.9.3).

The pressure

measurement mode indicator is <d>. The Q-RPT

position indicator is <Hd>.

Default DISPLAY function The default display function is RPT with the Lo Q-RPT

displayed on the bottom display line (see Section

3.3.6.4). This allows the line pressure (Lo Q-RPT

indication) to be viewed simultaneously with the

differential pressure. All other DISPLAY functions

(average, rate, deviation, HiLo, freeze) apply to

the differential pressure

SDS function

[SDS] key operation to OPEN SDS opens SDS of

both the Hi and Lo Q-RPTs simultaneously. (see

Section 3.3.8). Overpressure is driven by the pressure

range of the Lo Q-RPT (see Section 3.4.4.1).

AutoZ function

AutoZ manages zeroing of differential mode and is

intended to “tare” the two Q-RPTs at a common

line pressure (see Section 3.3.9.3). Switch to a

mode other than differential for AutoZ functions of

an individual Q-RPT.

Leak Check function

Head function

The leak check function uses the differential mode

measurement (see Section 3.3.5).

The head function applies to the differential

pressure (see Section 3.3.7).

AutoRange function

UL function

Differential measurement mode is not available in

AutoRange (see Section 3.3.4).

The UL limits apply to positive and negative

differential pressure (see Section 3.4.4) and the

default is the maximum value of the differential

pressure.

Both the Lo and Hi RPT base

measurement mode ULs also remain active. The

Hi RPT UL provides a upper limit for the maximum

pressure on the Hi side of the differential pressure.

Both the differential and base mode Hi RPT UL

cause the display of differential pressure to flash

when exceeded. The Lo RPT UL provides an

upper limit for the line pressure.

AutoTest function

The AutoTest function (see Section 3.3.10) is not

available in differential measurement mode.

3.3.4

[AUTORANGE]

PURPOSE

To automatically set up RPM4 to optimize its measurement characteristics and features for

specific, user specified range of operation.

PRINCIPLE

RPM4 is designed to support the calibration and test of a very wide variety of test ranges in

various measurement modes.

Page 30

3. OPERATION

The AutoRange function simplifies the task of selecting the Q-RPT best suited to cover a

specific test range and setting measurement parameters appropriately for the range. These are

set automatically based on operator entry of desired measurement mode, pressure unit of measure

and range full scale. The selections and settings made by AutoRange are summarized in Table 6.

A range set up using AutoRange and all its range specific settings, may be saved for recall

using [SETUP], <1range> (see Section 3.4.1). Saved ranges are available for later selection

using [RANGE] (see Section 3.3.1). If a range created by AutoRange is not saved, it is

overwritten by the next AutoRange or erased when another range is selected.

Press [ENT] from the main run screen in RATE mode to use the [AutoTest] function to

AutoRange RPM4 based on DUT tolerance (see Section 3.3.10).

Table 6. Settings Made by AutoRange

SETTING/SELECTION

PURPOSE

SET TO

SECTION

Unit

Set pressure unit of measure

Operator specified during

AutoRange

3.3.2

Mode

Set pressure measurement mode

(absolute, gauge, negative gauge)

Operator specified during

AutoRange

3.3.3

None

Full scale

Establish span maximum

Operator specified during

AutoRange

AutoRange span

Basis of span based setting

calculations

Absolute mode: Zero absolute

to AutoRange full scale

Gauge mode: Zero gauge to

AutoRange full scale

Negative gauge mode: Minus

atmosphere to AutoRange full

scale (negative equivalent of full

scale on BG15K Q-RPT).

Q-RPT

Select most appropriate Q-RPT

to cover range and mode.

1.2.2.1

Absolute and negative gauge

mode: Axxx Q-PRT with lowest

default full scale that is greater

than the AutoRange full scale

Gauge mode: Q-RPT with

lowest span whose full scale is

greater than AutoRange full

scale, Gxxx over Axxx if spans

are equal.

Upper limit

Lower limit

Set maximum and minimum

pressure alarm limits.

3.4.4

Upper limit: 105 % of operator

entered full scale pressure

Lower limit: None in absolute

and gauge modes. Minus

atmosphere in negative gauge

mode, minus equivalent of upper

limit in negative gauge mode on

a BG15K Q-RPT. Minus 66 kPa

(9.6 psi) with BA100K.

Resolution

Set display resolution

10 ppm of AutoRange span or

1 ppm of default Q-RPT span,

whichever is larger.

3.4.2

Stability Limit

Set Ready/Not Ready stability

criterion.

50 ppm of AutoRange span or 2

ppm of default Q-RPT span,

whichever is larger.

3.4.3,

3.3.4

Q-RPT turn down

(Premium class Q-RPTs only)

Turn down Q-RPT

See RPM4 pressure

measurement specifications

1.2.2.1

characterization to improve

measurement uncertainty when

span is reduced

Page 31

RPM4™ OPERATION AND MAINTENANCE MANUAL

OPERATION

To use the AutoRange function, press [AutoRange] and respond to the RPM4’s prompts.

Select AutoRange measurement mode: The screen is identical in appearance and

function to the [MODE] screen (see Section 3.3.3). The choice of measurement modes

offered reflects all the Q-RPT types available (Axxx, Gxxx, BGxxx) in the RPM4 system,

not just the active Q-RPT.

Differential pressure measurement mode (see Section 3.3.3.1) is not available in

AutoRange.

Select pressure unit of measure: The screen is identical in appearance and function

to the [UNIT] screen (see Section 3.3.2).

Altitude units of measure (m, ft) are not available for AutoRange.

Enter the AutoRange full scale pressure: Enter the full scale pressure value in the

<------> entry field and press [ENT]. If the full scale value entered cannot be covered by

any of the Q-RPTs available, an error message appears. If the full scale value can be

covered, AutoRange proceeds to the range display.

View proposed AutoRange range: The proposed AutoRange range screen is:

1. Indication that this is a screen of the proposed AutoRange range.

2. Designator and position of the Q-RPT that AutoRange has selected

to cover the AutoRange full scale and measurement mode.

3. Pressure unit of measure specified in AutoRange.

AutoRange A700K Hi

kPa 300g/100a

4. AutoRange full scale pressure in gauge mode and absolute

mode if available. Absolute mode only if AutoRange measurement

mode is absolute and full scale is less than 100 kPa (14.5 psi).

Gauge mode only if the Q-RPT is a Gxxx or BGxxx or an Axxx

with absolute mode turned off.

If the RPM4 has two Q-RPTs and you would like to select the other one for the

AutoRange, the cursor control keys may be used to toggle between Q-RPTs selections if

both Q-RPTs can handle the specified AutoRange.

Accept proposed AutoRange: To accept the proposed AutoRange and go to the MAIN

RUN screen with the AutoRange range active, press [ENT] or [AutoRange]. To modify

the AutoRange full scale, measurement mode or pressure unit of measure, use [ESC] to

back through the AutoRange screens and make changes.

To verify or confirm the range from the MAIN RUN screen, use [+/-] or [RANGE] to

view the active range (see Section 3.3.1).

See Table 6 for a listing of all selections and settings affected by AutoRange and

their default values.

The BA100K Q-RPT cannot be AutoRanged.

Page 32

3. OPERATION

3.3.5

[LEAK CK]

PURPOSE

To run an automated leak check routine that determines the leak rate of the system

connected to the RPM4 active Q-RPT TEST(+) port.

PRINCIPLE

The LEAK CHECK function is provided as a means of checking and quantifying the leaks that

may be present in the system connected to the RPM4’s active Q-RPT test port.

The principle of the LEAK CHECK function is the measurement of the natural decrease or

increase of pressure in a fixed volume over time. The LEAK CHECK function allows a leak

check time to be set. The total pressure change and the average rate of change over the

leak check time are calculated and displayed.

In differential pressure measurement mode (see Section 3.3.3.1), the leak check

measurement is based on the measurement of the differential pressure.

OPERATION

To run a leak check, first set the pressure to the desired leak check pressure.

Changing the pressure in a test system causes adiabatic temperature changes in the

pressurized medium that need to have dissipated before a valid leak measurement can be

made. In general, a 0.5 to 1 minute wait before running a leak check is adequate to allow

the adiabatic temperature change to dissipate and valid leak measurements to be made.

However, stabilization time may be much longer with liquid test media, and as volume and

pressure increases.

To access the LEAK CHECK function, press [LEAK CHECK] from the MAIN RUN screen.

Select <1run> to run a leak test. The display is:

Set leak check time:

1. Edit field for the time over which the leak rate will be

15 s

determined, in seconds.

Edit the leak check time if desired (minimum 1, maximum 999 seconds) and press [ENT].

Press [ENT] again when ready to start the leak test. The leak test display is:

1. Standard MAIN RUN screen first line showing measured

pressure.

957.84 kPa a

Leak testing

2. Active Q-RPT position indicator

13 s

Indication that leak test is running and countdown of time

remaining.

Page 33

RPM4™ OPERATION AND MAINTENANCE MANUAL

[ESC] can be used to abort the running leak test. [ENT] while the leak test is running

restarts the leak check timer. When the leak check timer countdown has completed,

RPM4 beeps three times and the leak check results screen is displayed:

1. Total pressure change from start to finish of leak check time.

∆P 0.61 kPa a Hi

2. Indicator of Q-RPT used to run the leak check.

Rate 0.06 kPa/sec

3. Average rate of change of pressure over the leak check

time period (∆P/time in seconds).

From the leak check results screen, press [ENT] to repeat the leak test.

Press [ESC] to return to leak check main menu and exit to the MAIN RUN screen.

To view the results of the most recently completed leak check, press <2view>. If NO leak

check data is stored (i.e., if the RPM4 has never run a leak test or a reset has cleared

previous leak test results), the results screen displays <Data NOT available> briefly and

returns to MAIN RUN screen. Press [ENT] or [ESC] to return to the MAIN RUN screen.

Leak check is range specific in the sense that a leak check is run using the active range.

However, only one set of leak check results is maintained in memory and each leak test

completed overwrites the memory. View leak check always shows the results of the last

leak check run regardless of the range that is now active. The results screen includes the

range indicator to indicate the range in which the leak check was run.

3.3.6

[DISPLAY]

PURPOSE

To select, from a variety of choices, the information that is displayed on the second line of the

RPM4 display.

PRINCIPLE

RPM4 supports a variety of advanced pressure measurement functions that are displayed on

the second (bottom) line of the RPM4 display. In summary, the available display functions

included are:

AVERAGE

Calculates the average pressure measurement over a user specified period

of time and displays the average, the standard deviation about the mean and

a countdown in seconds to the next average (see Section 3.3.6.1). This function

is often used to filter out pressure noise in an unstable system. The magnitude

of the noise is quantified by the standard deviation about the mean. A second

Avg screen allows the instantaneous pressure values to be viewed during an

averaging cycle.

RATE

Calculates and displays the current rate of change of pressure in current

pressure units/second (see Section 3.3.6.2). This function is a useful

indication of the stability of the pressure being measured. It is often used as

an indication of positive or negative leak rate and as a go/no go criterion of

when to take data when comparing RPM4 and a device under test, for

example in a calibration. Rate is used by the Ready/Not Ready function to

determine when a Ready condition exists (see Section 3.2.1).

DEVIATION

Continuously calculates and displays the difference between the pressure

measured by RPM4 and a target pressure entered by the user (see Section

3.3.6.3). This function is useful in monitoring the evolution of pressure around

and/or away from a desired set point.

Page 34

3. OPERATION

RPT

If the RPM4 has two Q-PRTs, allows pressure measurement from the two

RPTs to be displayed simultaneously (see Section 3.3.6.4). This function is

particularly useful in dual Q-RPT RPM4s with independent TEST ports to

monitor two separate pressures simultaneously. It is also used to when the

Hi Q-RPT is in differential measurement mode, to observe the line pressure

measured by the Lo Q-RPT.

HI/LO

Records and displays maximum and minimum pressures measured (see

Section 3.3.6.5). This function is used to keep track of the minimum and

maximum pressure observed in a system over a period of time or to monitor

if a pressure min/max limit has been exceeded..

FREEZE

Captures and displays the pressure measured by the active range of RPM4

when the [ENT] key is pressed (see Section 3.3.6.6). This function is useful

to record the pressure present at the time of an operator observed trigger

event, for example when the needle of an analog gauge was on the nominal

point or when a switch activates.

CLEAN

Blanks out the second line of the display (see Section 3.3.6.7). This function

is used when a simple display of pressure measured by the RPM4 active

range without additional information is desired.

OPERATION

To set the DISPLAY function press [DISPLAY] from the main run screen.

1avg 2rate 3dev 4RPT

5HiLo 6freeze 7clean

The display is:

The cursor is on the active DISPLAY function. Selecting a display function returns to the

main run screen with the selected function active.

Display menu choices include:

<1avg>

Display average pressure and standard deviation. Specify averaging time period

(see Section 3.3.6.1).

<2rate>

<3dev>

Display pressure rate of change (see Section 3.3.6.2).

Display deviation of the measured pressure from a target value and specify

the target value (see Section 3.3.6.3).

<4RPT>

Display the pressure measured by the second Q-RPT in RPM4s with two

Q-RPTs (see Section 3.3.6.4).

<5HiLo>

<6freeze>

<7clean>

Display the maximum and minimum pressure observed since HiLo reset

(see Section 3.3.6.5).

Capture and display the value measured when [ENT] is pressed

(see Section 3.3.6.6).

Leave the second line of the display blank (see Section 3.3.6.7).

The DISPLAY selection is NOT range specific. A DISPLAY selection made in one range

applies to all ranges.

The default DISPLAY function is Rate which causes the second line of the display to show “R”

followed by the current rate of change of pressure in current pressure units per second.

The default DISPLAY function in differential mode is RPT.

Page 35

RPM4™ OPERATION AND MAINTENANCE MANUAL

When RPM4 is initialized as an external device to a PPC3 pressure controller, the RPM4

front panel keypad is locked out and the second line of the display becomes:

<PPC3 EXT DEV: IDLE> (if RPM4 is initialized by PPC3 but not currently in use)

<PPC3 EXT DEV: ACTIVE> (if RPM4 is initialized by PPC3 and is currently in use)

After using an RPM4 as an external device for a PPC3, cycle power to return to the

previous RPM4 settings, restore front keypad capability and return to the normal main

run screen.

3.3.6.1

AVG (AVERAGE)

PURPOSE

To activate the Average DISPLAY and/or adjust the period of time over which

averaging occurs.

See Section 3.3.6. Principle.

OPERATION

To access the Average DISPLAY, press [DISPLAY], <1Avg>. The display is:

Averaging Period:

1. Edit field for averaging period in seconds.

20 s

Default is 20. Minimum 1, maximum 999.

Edit the averaging time period if desired. Pressing [ENT] returns to the main run

screen with the Average DISPLAY active.

With the Average DISPLAY active the main run screen is:

1. Average measured over last completed

averaging period.

96.929 kPa a

2. Standard deviation of last completed

averaging period.

δ 0.0007

18Avg

3. Countdown in seconds until completion of on-

going averaging period.

The Average DISPLAY has a second screen that allows the instantaneous

pressure readings to be viewed while an averaging cycle is running.

The instantaneous Average screen is:

1. Instantaneous pressure values at RPM4’s

normal update rate.

96.929 kPa a

18Avg

2. Current rate of change of pressure in pressure

units/second.

R 0.0025

3. Countdown in seconds until completion of on-

going averaging period.

The [+/-] key toggles between the main run Average screen and the

instantaneous values Average screen.

Page 36

3. OPERATION

Pressing [ENT] while in the Average DISPLAY aborts the current averaging

period and causes a new one to begin. [ENT] can thus be use to trigger a

new averaging period on demand.

In the Average DISPLAY the Ready/Not Ready indication applies to the result

of the previous averaging period (see Section 3.2.1). <Ready> indicates that

all readings during the previous averaging period met the stability criterion.

<Not Ready> indicates that one or more readings were outside of the

stability criterion.

Changing the pressure unit of measure, measurement mode or range while

the averaging screen is active, starts a new averaging period.

To go to a DISPLAY other than Average, press [DISPLAY] and make a new

DISPLAY choice (see Section 3.3.6).

3.3.6.2

Rate

PURPOSE

To activate the Rate DISPLAY.

See Section 3.3.6 [DISPLAY], Principle.

The AutoTest function (see Section 3.3.10) to AutoRange RPM4 based on

DUT characteristics and run an automated test sequence is accessed by

pressing [ENT] from the Rate run screen.

OPERATION

To activate the Rate DISPLAY press [DISPLAY], <2Rate>. Pressing <2Rate>

returns to the main run screen with the Rate DISPLAY active.

With the Rate DISPLAY active the main run screen is:

99.1135 psi a Hi

1. Current rate of change of pressure in current

R 0.0001/sec

pressure units per second.

The Rate DISPLAY is different and separate from the stability setting which

is used to set the stability criterion on which the Ready/Not Ready

indication is based (see Sections 3.4.3 and 3.2.1). The Rate DISPLAY only

causes the current rate of change to be displayed and has NO affect on the

stability setting or the Ready/Not Ready condition.

Page 37

RPM4™ OPERATION AND MAINTENANCE MANUAL

The Rate DISPLAY is the default display except in differential measurement

mode in which the default DISPLAY is RPT.

To go to a DISPLAY other than Rate, press [DISPLAY] and make a new

DISPLAY choice (see Section 3.3.6).

3.3.6.3

Dev (Deviation)

PURPOSE

To activate the Deviation DISPLAY and/or set the deviation target value.

See Section 3.3.6 [DISPLAY], Principle.

OPERATION

Target:

To activate the Deviation DISPLAY press

[DISPLAY], <3Dev>. The display is:

100.0000 psi a

Edit the desired target value. Pressing [ENT] returns to the main run screen with

the Deviation DISPLAY active using the entered target value.

The target value is the value from which deviations (D) are measured by the

Deviation DISPLAY following:

D = current pressure - target pressure

With the Deviation DISPLAY active the main run screen is:

99.1135 psi a zH3

1. Deviation of current pressure from the target

value.

D -0.8865 T100.0000

2. Target value.

Pressing [ENT] from the main run screen when the Deviation DISPLAY is

active goes directly to the Target editing screen. This allows the target

value to be changed without going through the DISPLAY menu.

If the pressure measurement unit or mode is changed while the Deviation

DISPLAY is active the target value remains at the same numerical value.

It is NOT converted.

To go to a DISPLAY other than Deviation, press [DISPLAY] and make a new

DISPLAY choice (see Section 3.3.6).

Page 38

3. OPERATION

3.3.6.4

RPT

PURPOSE

To activate the RPT DISPLAY.

See Section 3.3.6, Principle.

The RPT DISPLAY is only available in RPM4s with two Q-RPTs.

OPERATION

For the sake of clarity, when describing the RPT DISPLAY, the Q-RPT

displayed on the top line of the display when the RPT function is selected is

referred to as the “active” Q-RPT. The other Q-RPT to be displayed on the

second (bottom) line of the RPM4 display is referred to as the “inactive”

Q-RPT. It is “inactive” in the sense that all RPM4 functions and settings

such as UNIT and RES still apply to the “active” Q-RPT. To make changes to

the “inactive” Q-RPT, for example to change its measurement units, it must

be made the active Q-RPT by a conventional range change (see Section 3.3.1).

In differential pressure measurement mode, the Hi Q-RPT is always the

“active” Q-RPT.

To activate the RPT DISPLAY, press [DISPLAY], <4RPT>. Operation returns to

the MAIN RUN screen with the inactive Q-RPT displayed on the display’s bottom

line. The range of the inactive Q-RPT is always the default range, not an

AutoRanged range (see Section 3.3.4).

If the RPM4 has only one Q-RPT, <Not available with single RPT> displays

momentarily and operation returns to the main run screen when [DISPLAY],

<4RPT> is pressed.

If the RPM4 is in parallel (<HL>) (see Section 3.5.7.3) mode in which both

Q-RPTs are used simultaneously, when <4RPT> is selected, the Q-RPT to display

on the lower display line must be specified. The Q-RPT specific settings of the

Q-RPT displayed in the lower display line (measurement mode, unit of measure,

resolution, etc.) can only be changed by making that Q-RPT active.

With the RPT DISPLAY active the main run screen is:

1. Active RPT display.

99.1135 psi a zHi

2. Inactive RPT display with Ready/Not Ready

*2350.23 psi g zLo

indicator on far left.

Page 39

RPM4™ OPERATION AND MAINTENANCE MANUAL

If the inactive RPT is equipped with SDS Self Defense System (see Section

3.2.7), SDS will almost certainly be CLOSED when the RPT DISPLAY is activated.

SDS can be OPENED on the inactive RPT using [SPECIAL], <4SDS> (see Section

3.5.4). In differential or parallel measurement mode, SDS can be opened

simultaneously on both Q-RPTs using [SDS] (see Section 3.3.8).

The RPT DISPLAY is the default display in differential measurement mode.

When the RPT display is active, executing a range change to a range on the

inactive Q-RPT makes the inactive Q-RPT the active Q-RPT. The DISPLAY

defaults back to Rate ( Section 3.3.6.2).

To go to a DISPLAY other than RPT, press [DISPLAY] and make a new

DISPLAY choice (see Section 3.3.6).

3.3.6.5

Hi/Lo

PURPOSE

To activate the Hi/Lo DISPLAY.

See Section 3.3.6, Principle..

OPERATION

To activate the Hi/Lo DISPLAY press [DISPLAY], <5Hi/Lo>. Pressing <5Hi/Lo>

resets the Hi/Lo values and returns to the main run screen with the Hi/Lo

DISPLAY active.

With the Hi/Lo DISPLAY active the main run screen is:

99.1135 psi a zHi

1. Highest pressure observed since Hi/Lo reset.

H 99.2254 L98.0098

2. Lowest pressure observed since Hi/Lo reset.

The Hi/Lo values change each time a new Hi or Lo pressure is observed.

The Hi/Lo record can be reset at any time by pressing [ENT]. This allows a

Hi/Lo reset without going back through the DISPLAY menu.

If the pressure measurement unit, mode or range is changed while the Hi/Lo

DISPLAY is active, Hi/Lo resets.

To go to a DISPLAY other than Hi/Lo, press [DISPLAY] and make a new

DISPLAY choice (see Section 3.3.6).

Page 40

3. OPERATION

3.3.6.6

Freeze

PURPOSE

To activate the Freeze DISPLAY.

See Section 3.3.6, Principle.

OPERATION

To activate the Freeze DISPLAY press [DISPLAY], <6Freeze>. Pressing

<6Freeze> returns to the main run screen with the Freeze DISPLAY active.

With the Freeze DISPLAY active the main run screen is:

99.135 psi a zHi

1. Pressure measured by active range of RPM4

when [ENT] was pressed (displays 0.00 by

default when Freeze DISPLAY is first

activated).

F 99.2133

Pressing [ENT] causes the current pressure measured by the active RPM4 Q-RPT

to be captured and displayed.

If the pressure measurement unit, mode or range is changed while the Freeze

DISPLAY is active, the Freeze value defaults back to zero.

To go to a DISPLAY other than Freeze, press [DISPLAY] and make a new

DISPLAY choice (see Section 3.3.6).

3.3.6.7

Clean

PURPOSE

To activate the Clean DISPLAY.

See Section 3.3.6, Principle..

The AutoTest function (see Section 3.3.10) to AutoRange RPM4 based on

DUT characteristics and run an automated test sequence is accessed by

pressing [ENT] from the Rate run screen.

Page 41

RPM4™ OPERATION AND MAINTENANCE MANUAL

OPERATION

To activate the Clean DISPLAY press [DISPLAY], <7Clean>. Pressing <7Clean>

returns to the main run screen with the Clean DISPLAY active.

With the Clean DISPLAY active the main run screen is:

1. Conventional main run screen first line.

99.135 psi a zHi

2. “Clean” second line.

To go to a DISPLAY other than Clean, press [DISPLAY] and make a new

DISPLAY choice (see Section 3.3.6).

3.3.7

[HEAD]

PURPOSE

To cause a pressure fluid head correction to be added to or subtracted from the pressure

measured by the RPM4 reference pressure transducer in order to predict the pressure at a

height other than the RPM4’s reference level.

PRINCIPLE

RPM4 measures gauge or absolute pressure at the height of the rear panel TEST(+) port.

Frequently, when performing a calibration or test, the device or system under test is at a

different height than the RPM4’s TEST(+) port. This difference in height, frequently called

head, can cause a significant difference between the pressure measured by the RPM4 at its

TEST(+) port height and the pressure actually applied to the device under test which is at a

different height. In this case, it is useful to make a head correction to the pressure measured

by the RPM4 in order to predict the pressure actually applied at a different height.

RPM4 can accurately determine “head” pressures for gases (nitrogen, helium and air) and

liquids (oil, water) as the pressurized medium. In calculating the head value, standard gravity

(9.80665 m/s²) is used. Gas densities are calculated from the selected gas’s standard

density correcting for temperature of 20°C and the measured pressure using the gas’s

compressibility factor to 100 MPa (15 000 psi) and extrapolated above 100 MPa. Oil density

is taken to be 850 kg/m³, the density of typical calibration oils at 20°C. Water density is taken

to be 998.2321kg/m³(20°C). A custom liquid density may also be specified.

The [HEAD] function key is used to specify the height difference between the RPM4 TEST(+)

port and another height. Entering a height of zero turns the function off. The height unit and

the test fluid are specified by pressing [SPECIAL], <3Head> (see Section 3.5.3).

Use of the HEAD function to assure in tolerance measurements is most important in low

absolute pressure ranges. Specifying the head height within ± 5 cm (2.5 in.) is adequate

to assure that, even in the worst case, the uncertainty on the head correction will be

insignificant relative to the tolerance on the measurement.

Page 42

3. OPERATION

OPERATION

To access the HEAD function, press [HEAD]. The display is:

Edit head height:

+ 25 cm N2

1. Test fluid currently specified for the head correction.

2. Edit field for head height.

Edit the head height to the desired value. Press [ENT] to return to the MAIN RUN screen

with the new head correction active. Press [ESC] to return with no changes.

The reference height of the RPM4

pressure measurement is the middle of

the RPM4 TEST port. The head height

should be entered as a positive value if

the device or system under test is

higher than the RPM4 and negative if it

is lower.

The HEAD function is NOT range specific. The HEAD ON or OFF status remains the same

as Q-RPTs and ranges are changed. Edits made to the head settings are independent of

active range or Q-RPT.

When a head correction is being applied, it is indicated by <h> in the top line of the MAIN

RUN screen (see Section 3.1.1). When the head correction is zero, the <h> is not shown.

To change units of head height between inches and centimeters and to change the test

fluid species, use [SPECIAL], <3head> (see Section 3.5.3).

3.3.8

[SDS] (SELF DEFENSE SYSTEM)

PURPOSE

To CLOSE SDS on all reference pressure transducers (Q-RPTs). To OPEN SDS on the

active Q-RPT.

SDS is present only on Q-RPTs designated A7M or lower.

The [SDS] key should be used with care to avoid accidentally overpressuring a Q-RPT.

Always double check to ensure that the pressure applied to the Q-RPT’s TEST port is

lower than the Q-RPT’s maximum pressure before OPENING SDS.

SDS can be set to permanently be OPEN as if no SDS were installed (see Section

3.5.4.2).

Page 43

RPM4™ OPERATION AND MAINTENANCE MANUAL

PRINCIPLE

SDS is a self defense system to protect RPM4 Q-RPTs from overpressure. SDS CLOSES

automatically to protect a Q-RPT that is not active. In a two Q-RPT RPM4, activating one

Q-RPT automatically CLOSES SDS on the other Q-RPT. Powering down the RPM4 or

energizing it also CLOSES SDS on all Q-RPTs.

When a Q-RPT’s module’s SDS is CLOSED, the Q-RPT is isolated from the TEST(+) port

and opened to the VENT port. SDS must be OPENED for the pressure applied to the

TEST(+) port to be measured. The [SDS] key is used to OPEN SDS.

The SDS function can also be used to CLOSE SDS as might be desired when leaving RPM4

at rest or when a possible overpressure situation is anticipated. Pressing [SDS] always

CLOSES any SDS systems that are OPEN.

See Section 3.2.7 for general information on SDS and its principles and Section 5.6,

Figure 8 for Q-RPT module schematics.

SDS closed is indicated by <SDS CLOSED> flashing in the current measured pressure

display field. When SDS is closed, the Q-RPT is isolated from the TEST(+) port and

connected to the VENT port.

OPERATION

Though the SDS self defense system includes features to protect Q-RPTs against

overpressure, SDS should NOT be considered a fail-safe overpressure protection system.

SDS cannot guarantee that overpressure damage will NOT occur. SDS closing automatically

may protect an RPT in case of accidental overpressure but conventional measures for

overpressure protection should always be used. Damage to Q-RPTs due to overpressure

is NOT covered by the RPM4 product warranty even when SDS is present and ON.

The maximum pressure that should be applied to an RPM4 TEST(+) port when SDS is

CLOSED is 10 MPa (1 500 psi).

When SDS is CLOSED with a pressure applied, a valve shuts isolating the Q-RPT from the

TEST(+) port. Another valve vents the Q-RPT to atmosphere through the VENT port.

If the pressure applied at the time SDS is CLOSED is less than 1 700 kPa (250 psi),

the VENT valve will open causing sudden release of pressure through the VENT port and

returning the Q-RPT to atmospheric pressure. If the pressure applied at the time SDS is

CLOSED is greater than 1 700 kPa, the VENT valve may NOT open. In this case, to vent

pressure from the Q-RPT module, remove the pressure from the TEST(+) port. This will

cause the SDS TEST port isolation valve to open partially, reducing pressure under

1 700 kPa at which time the SDS VENT valve will open (see Section 5.6, Figure 8)

Pressing [SDS] always CLOSES any SDS system that is OPEN. In a dual Q-RPT RPM4,

even if the active Q-RPT has NO SDS, pressing [SDS] CLOSES SDS for the inactive Q-RPT

if SDS is present.

Page 44

3. OPERATION

Use [SDS] to OPEN SDS if it is CLOSED for the active Q-RPT and/or to CLOSE SDS for the

active and inactive Q-RPT.

When [SDS] is pressed, there are three possible results depending whether the active Q-RPT is

SDS equipped and ON (see Section 3.5.4.2), and whether its SDS is OPEN or CLOSED.

1. If the active Q-RPT IS NOT SDS equipped or its SDS if “full time OFF” (see Section 3.5.4.2):

<No SDS on RPT> or <SDS is OFF and OPEN> is displayed for 5 seconds and

operation returns to the main run screen. If there is a second Q-RPT with SDS, its SDS

is CLOSED.

2. If the active RPT IS SDS EQUIPPED and SDS on the active RPT is OPEN:

SDS is CLOSED and operation returns to the main run screen.

3. If the active RPT IS SDS EQUIPPED and SDS on the active RPT is CLOSED:

The OPEN SDS routine is presented. The display is :

1. Maximum acceptable pressure of active Q-RPT (always

absolute on an Axxx Q-RPT and gauge on a Gxxx Q-RPT).

Pmax! 350 kPa a Hi

2. Position designator of Q-RPT for which SDS will be

opened.

Open SDS? 1no 2yes

Check that the pressure applied to the TEST(+) port does NOT exceed the maximum

acceptable value for the Q-RPT. Select <1no> to return to the main run screen without

OPENING SDS, select <2yes> to OPEN SDS and return to the main run screen with

SDS OPEN (the active Q-RPT open to the TEST(+) port).

Opening SDS with a pressure greater than Pmax! applied to the test port may cause

overpressure damage to the Q-RPT.

In differential and parallel measurement modes, opening SDS acts simultaneously on

BOTH THE Hi AND Lo Q-RPTs (see Section 3.3.8.1). The Pmax! pressure is the Lo RPT.

Be sure to check BOTH Q-RPT TEST(+) ports are at a safe pressure before opening SDS.

The [SDS] key is also the [2] key which is pressed to select <2Yes> to OPEN SDS.

Thus, SDS can be OPENED by two rapid presses of [SDS]. Use this feature to

conveniently OPEN SDS but always check that the pressure connected the TEST(+) port

does NOT exceed Pmax! before doing so.

When changing ranges causes a change of active Q-RPT, SDS is automatically CLOSED for

the Q-RPT that is being changed from, leaving the inactive Q-RPT with SDS CLOSED.

The Lo and Hi Q-RPTs’ SDS, if present, can be controlled directly regardless of which

Q-RPT is currently active (see Section 3.5.4).

SDS can be permanently opened so operation is as if SDS were not present

(see Section 3.5.4.2).

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RPM4™ OPERATION AND MAINTENANCE MANUAL

3.3.8.1

SDS IN DIFFERENTIAL AND PARALLEL MEASUREMENT

MODES

In differential and parallel measurement modes, opening SDS opens SDS for

BOTH the Hi and Lo Q-RPTs. Before opening SDS, be certain that the

pressure applied to both the Hi and Lo RPM4 TEST(+) ports is less than the

maximum pressure of the Lo Q-RPT.

Differential (see Section 3.3.3.1) and parallel measurement modes (see Section

3.5.7.3) use two Q-RPTs in one RPM4 to simultaneously. In these modes,

function of the [SDS] key is adapted to facilitate operation using both Q-RPTs

simultaneously. [SDS] can be used to OPEN SDS on both the active an inactive

Q-RPTs at the same time.

Pressing [SDS] always CLOSES any ON and OPEN SDS, as it does in single Q-RPT

mode operation. However, if SDS is CLOSED for any and all modules equipped

with SDS, pressing SDS goes to the usual OPEN SDS routine which will OPEN

SDS for both Q-RPTs.

The display is :

1. Maximum acceptable pressure of the Lo

Q-RPT (always absolute on an Axxx Q-RPT

and gauge on a Gxxx Q-RPT).

Pmax! 350 kPa a HL

2. Position designator of active Q-RPT. <HL> in

Open Hi&Lo? 1no 2yes

parallel mode, <Hd> in differential mode.

Check that the pressure applied to BOTH the TEST(+) ports does NOT exceed

the maximum acceptable value for the Lo Q-RPT. Select <1no> to return to the

main run screen without OPENING SDS, select <2yes> to OPEN SDS for both

Q-RPTs and return to the main run screen with SDS OPEN (the active Q-RPT

open to the TEST(+) port).

3.3.9

[AUTOZ]

PURPOSE

To run the AutoZ function that rezeros the active Q-RPT between full calibrations.

See Section 3.5.1, Principle for a full explanation of the AutoZ function.

PRINCIPLE

Run AutoZ is the function by which the current Q-RPT reading is compared to a reference,

P_std,0, at atmospheric pressure to determine a new value of P_offset. The value of P_offsetis then

used by AutoZ to automatically correct the Q-RPT for possible changes in zero over time

(see Section 3.5.1, PRINCIPLE).

Running AutoZ in parallel mode (see Section 3.5.7.3) autozeros the Hi and Lo Q-RPTs

simultaneously and independently. There is are no Zoffset values specific to the HL Q-

RPT.

See Section 3.3.9 to run AutoZ.

Page 46

3. OPERATION

3.3.9.1

[AUTOZ] IN GAUGE AND NEGATIVE GAUGE MODE

PURPOSE

To “rezero” the active Q-RPT in gauge measurement mode.

See Section 3.5.1, Principle for a full explanation of the AutoZ function.

OPERATION

For the AutoZ function key to run AutoZ, AutoZ must be turned ON for the

active range and measurement mode. AutoZ ON is indicated by <z> to the

left of the Q-RPT designator on the first line of the main run screen. AutoZ

ON and OFF is set using [SPECIAL], <1AutoZ> (see Section 3.5.1). If AutoZ

is OFF for the active Q-RPT, and measurement mode, <AutoZ is off >

is displayed when [AutoZ] is pressed.

Running AutoZ in or parallel mode (see Section 3.5.7.3) autozeros both the

Hi and Lo Q-RPTs simultaneously.

To run AutoZ in gauge measurement mode, set gauge or negative gauge as the

measurement mode (see Section 3.3.3) and press [AutoZ] from the main run

screen. If the Q-RPT is a Gxxx or BGxxx type, the display is <Preparing to

AutoZ> for five seconds to allow time for the bypass valve between the TEST(+)

and TEST(-) sides of the Q-RPT to assure zero differential pressure and for the

pressure to stabilize (see Section 5.6, Figure 8). <Running gauge AutoZ> is

displayed briefly before returning to the main run screen.

Before running AutoZ in gauge mode, ensure that the pressure applied to

the Q-RPT is truly zero gauge (atmospheric pressure). If running AutoZ in

gauge mode results in a zero offset that RPM4 considers unusually large,

<Confirm 0 gauge P!> is displayed when AutoZ is pressed. Check that zero

gauge pressure is applied to the TEST(+) port and there is no differential

pressure across the TEST(+) and TEST(-) ports and press ENTER to

continue or ESCAPE to abort.

Allow the RPM4 to stabilize at atmospheric pressure and ambient

temperature for 1 to 2 minutes before running AutoZ in gauge mode.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

3.3.9.2

[AUTOZ] IN ABSOLUTE MODE

PURPOSE

To “rezero” the active Q-RPT in absolute measurement mode

See Section 3.5.1, Principle for a full explanation of the AutoZ function.

OPERATION

For the AutoZ function key to run AutoZ, AutoZ must be turned ON for the

active Q-RPT and measurement mode. AutoZ ON is indicated by <z> to the

left of the range designator on the first line of the main run screen. AutoZ

ON and OFF is set using [SPECIAL], <1AutoZ> (see Section 3.5.1). If AutoZ

is OFF for the active range, and measurement mode, <AutoZ OFF> is

displayed when [AutoZ] is pressed.

Running AutoZ in or parallel mode (see Section 3.5.7.3) autozeros both the

Hi and Lo Q-RPTs simultaneously.

To run AutoZ in absolute measurement mode, set absolute measurement mode

(see Section 3.3.3) and press [AutoZ] from the main run screen. The display is:

1. Active Q-RPT designator.

AutoZ Hi abs by:

2. Current measurement mode (absolute).

1Entry 2COM2 3Lo RPT

3. Selection of source of P_std,0reference to which

to AutoZ.

Selecting <1Entry> allows the value of P_std,0to be entered from the front panel keypad.

Selecting <2COM2> allows the value of P_std,0to be read automatically from another

DHI RPMx connected to RPM4’s COM2 communications port.

Selecting <3Lo RPT> is shown only if the active Q-RPT is Hi and there is a Lo

Axxx Q-RPT in the RPM4. This selection allows the value of P_std,0for the Hi

Q-RPT to be read automatically from the RPM4s Lo Q-RPT.

Allow the RPM4 to stabilize at atmospheric pressure and ambient

temperature for 10 to 15 minutes before running AutoZ in absolute mode.

If running AutoZ results in a value of P_offsetthat is greater than ± 0.005 % FS of

the span of the Q-RPT that is being AutoZeroed, the Q-RPT and/or the reference

used as the source of P_std,0may be out of tolerance or the AutoZ process may

have been faulty. Before activating a new P_offsetgreater than ± 0.005 % FS of

the active Q-RPT, check to be sure that both the Q-RPT and the reference

were in good working order, properly vented to stable atmospheric pressure,

at the same height, and reading in the same pressure units when AutoZ was run.

Page 48

3. OPERATION

When the run AutoZ selection is made, if a HEAD correction is currently active

(see Section 3.3.7) the head correction is momentarily disabled while running

AutoZ to avoid “zeroing out” the head value.

The value of P_offsetis always displayed and entered in Pascal (Pa).

Run AutoZ by Entry

AutoZ by entry allows the value of P_std,0(see Section 3.5.1, PRINCIPLE) to be

entered directly from the RPM4 front panel. This provides a simple way of

AutoZeroing relative to an independent reference device such as a house

barometer that does not interface directly with RPM4.

To access run AutoZ by entry press [AutoZ], <1entry>. The display is:

1. Real time pressure reading (without head

correction), pressure unit of measure and

measurement mode of the active Q-RPT.

96.7755 kPa a

Pstd,0:0.00000

2. Active Q-RPT position designator.

3. Entry field for the value of P_std,0. in the current

pressure unit of measure.

Enter the value of the AutoZ reference (P_std,0) in the same unit of measure as the

top line display and press [ENT]. RPM4 logs the reading and calculates a new

AutoZ offset value. The next display is:

Press [ENT] to activate the new value of

P_offsetor [ESC] to start over with entry of a

new AutoZ reference (P_std,0) value.

Old P_offset: 0.0 Pa

New P_offset: 8.3 Pa

The value of P_offsetis always in Pascal (Pa). The value of P_std,0is entered in

the current pressure unit of measure.

Run AutoZ by COM2

AutoZ by COM2 allows the value of P_std,0(see Section 3.5.1 Principle) to be read

automatically from a DHI RPMx connected to the RPM4 COM2 communications

port. The RPMx is read and the new P_offsetis calculated automatically.

Page 49

RPM4™ OPERATION AND MAINTENANCE MANUAL

To access run AutoZ by COM2 press [AutoZ], <2COM2>. The display is:

1. Real time pressure reading (without head

correction), pressure unit of measure and

measurement mode of the active Q-RPT.

96.7755 kPa a

Pstd,0:0.00000

2. Active Q-RPT position designator.

3. Real time reading from the RPMx connected

to RPM4’s COM2 communications port.

Observe the displayed pressures and verify that they are stable. When ready,

press [ENT] to cause AutoZ to run. RPM4 logs both readings and calculates a

new AutoZ offset value. The display is:

Old P_offset: 0.0 Pa

New P_offset: 3.1 Pa

Press [ENT] to activate the new value of

P_offsetor [ESC] to start over.

For RPM4 to communicate with an RPMx connected to its COM2 port, the

RPM4 and the RPMx RS-232 interfaces must be set up properly

(see Section 3.5.2). If, the RPM4 is unable to communicate with an RPMx via

COM2 when running AutoZ by COM2, it times out after 6 seconds and

displays <RPM NOT detected>.

The value of P_offsetis always displayed and entered in Pascal (Pa).

Run AutoZ by Lo RPT

AutoZ by Lo RPT is available only if the active Q-RPT is the Hi Q-RPT and there

is an Axxx Lo Q-RPT. AutoZ by Lo RPT allows the Lo Q-RPT in an RPM4 to serve

as the AutoZ reference (source of P_std,0) (see Section 3.5.1, PRINCIPLE).

The Lo Q-RPT is read and the new P_offsetis calculated automatically.

To access run AutoZ by Lo RPT press [AutoZ], <3Lo RPT>. The display is:

1. Real time pressure reading (without head

correction), pressure unit of measure and

96.7755 kPa a

Pstd,0:97.7786

measurement mode of the active Q-RPT.

2. Active Q-RPT position designator.

3. Real time reading from the Lo Q-RPT.

Observe the displayed pressures and verify that they are stable. When ready,

press [ENT] to cause AutoZ to run. RPM4 logs both readings and calculates a

new AutoZ offset value. The display is:

Old P_offset: 0.0 Pa

New P_offset: 3.1 Pa

Press [ENT] to activate the new value of

P_offsetor [ESC] to start over.

The value of P_offsetis always displayed and entered in Pascal (Pa).

Page 50

3. OPERATION

3.3.9.3

AUTOZ IN DIFFERENTIAL MODE

PURPOSE

To compensate for the offset between the Hi Q-RPT and the Lo Q-RPT at the

operating “line pressure” in differential measurement mode.

See Section 3.5.1, Principle for a full explanation of the AutoZ function.

OPERATION

For the AutoZ function key to run AutoZ, AutoZ must be turned ON for the

active range and measurement mode. AutoZ ON is indicated by <z> to the

left of the Q-RPT designator on the first line of the main run screen. AutoZ

ON and OFF is set using [SPECIAL], <1AutoZ> (see Section 3.5.1). If AutoZ

is OFF for the active Q-RPT, and measurement mode, <AutoZ is off > is

displayed when [AutoZ] is pressed.

To run AutoZ in differential measurement mode, set differential as the

measurement mode (see Section 3.3.3) and press [AutoZ] from the main run

screen. <Running differential AutoZ> is displayed briefly before returning to the

main run screen.

Before running AutoZ in differential mode, set the “line pressure” at which

the differential measurements will be made and assure that a common

pressure is applied to both Q-RPTs. If running AutoZ in differential mode

results in a zero offset that RPM4 considers unusually large, <Confirm 0

DP> is displayed when AutoZ is pressed. Check that zero differential

pressure is applied across the Hi and Lo TEST(+) ports and press ENTER to

continue or ESCAPE to abort.

Allow the RPM4 to stabilize at atmospheric pressure and ambient

temperature for 2 to 3 minutes before running AutoZ in differential mode.

3.3.10 [ENT] (RUN AUTOTEST)

PURPOSE

To run the AutoTest function which AutoRanges the RPM4 and runs a calibration test based

on user entries of pressure unit, measurement mode, full scale, increment and DUT

tolerance.

Run AutoTest is accessed by pressing [ENT] from the Rate or Clean DISPLAY mode (see

Section 3.3.6.2). In other DISPLAY modes, the function of [ENT] is specific to the mode.

Page 51

RPM4™ OPERATION AND MAINTENANCE MANUAL

PRINCIPLE

This feature not available at the time of release of this manual. Check www.dhinstruments.com

for new RPM4 embedded software releases and manual updates.

OPERATION

Feature not available at the time of release of this manual.

3.4

[SETUP]

PURPOSE

[SETUP] accesses a menu of functions and features commonly used in setting up and using RPM4.

OPERATION

1range 2res 3stab

4UL 5ATest

To access the SETUP menu, press [SETUP] from the MAIN RUN

screen. The display is:

SETUP menu choices include:

<1range>

<2res>

Save and delete ranges created by AutoRange (see Section 3.4.1).

Adjust the resolution of pressure displays (see Section 3.4.2).

<3stab>

Adjust the pressure stability test that is the criterion for the Ready/Not Ready indication

(see Section 3.3.3).

<4UL>

Adjust upper and lower pressure limit alarms (see Section 3.4.4).

<5ATest>

View data files resulting from running QDUT AutoTests (See Section 3.4.5).

3.4.1

<1RANGE>

PURPOSE

Save AutoRange ranges and associated settings for recall. Delete previously saved AutoRange ranges.

PRINCIPLE

The RPM4 AutoRange function creates a range and automatically sets various operating

parameters proportionally to the range (see Section 3.3.4). Operating settings can then be

changed by the user. Many operating settings are specific to the current range (see Table 4).

[SPECIAL], <1range> allows the AutoRange range and associated settings to be saved for

recall using the [RANGE] key (see Section 3.3.1). This can avoid having to recreate

frequently used ranges and settings.

[SPECIAL], <1range> is also used to delete ranges that have been saved but are no longer needed.

3.4.1.1

SAVING AN AUTORANGE RANGE

OPERATION

To save a range created by AutoRange, the range must be the active range.

Use AutoRange to create the range (see Section 3.3.4) and then make any

desired feature and setting adjustments.

Page 52

3. OPERATION

Once the AutoRange range is set up as desired, press [SETUP], <1range>,

<1save>. The display is:

1. Indication that this is a range to be saved.

2. Designator and position of the Q-RPT used by

the range to be saved.

Save range A700K Hi

3. Pressure unit of measure of the range to be

kPa 300g/100a

saved.

4. Full scale pressure of the range to be saved in

gauge mode and absolute mode if available.

Press [ENT] to save the range or [ESC] to return to the MAIN RUN screen without

saving the range.

Default (<DF>) Q-RPT ranges cannot be saved. They are permanent.

Duplicate AutoRange ranges cannot be saved. A duplicate AutoRange range

is a range that has the same measurement mode and full scale and uses the

same Q-RPT as a range that has already been saved.

3.4.1.2

DELETING AUTORANGE RANGES

OPERATION

To delete a single saved AutoRange range, press [SETUP], <1range>, <2delete>.

If there are any saved ranges available to delete, the display is:

1. Indication that the cursor control keys may be

used to toggle through the saved ranges to

select the one to be deleted.

2. Designator and position of the Q-RPT used by

< and > A700K Hi

the range to be deleted.

kPa 300g/100a

3. Pressure unit of measure of the range to be

deleted.

4. Full scale pressure of the range to be deleted

in gauge mode and absolute mode if available.

Use the cursor control keys to toggle through the ranges available to be deleted.

When the desired range to be deleted is displayed, press [ENT]. If you are sure you

want to delete this range, press [ENT] again in response to the <Delete?> query.

[ESC] returns to the <AutoRange:> screen without deleting a range.

To delete all of the saved AutoRange ranges, press [SETUP], <1range>,

<3delete all>. If you are sure you want to delete all the ranges, respond <1yes>

to the <Delete all saved ranges?> query. If not, respond <2no>.

3.4.2

<2RES> (RESOLUTION)

PURPOSE

To set the resolution with which measured pressures and other pressure indications and

settings are displayed.

PRINCIPLE

The resolution with which RPM4 displays pressure values can be adjusted. This feature can

be used to reduce the resolution when lower precision measurements are being made and

excess resolution might confuse or distract the operator.

The resolution setting determines the number of digits with which pressure is displayed.

The resolution is calculated based on the span of the range and then rounded to the furthest

Page 53

RPM4™ OPERATION AND MAINTENANCE MANUAL

digit to the right. For example, resolution of 0.001 % on a range of 150 kPa is

150 X 0.001 % = 0.0015 which is rounded down to 0.001 kPa.

Default resolution is 10 ppm of active range span. Resolution is set automatically by

AutoRange (see Section 3.3.4).

OPERATION

Display resltn: Hi

0.0010 %FS < and >

To access the resolution function, press [SETUP],

<2res>. The display is:

Use the cursor control keys to set the desired level of resolution. Press [ENT] to return to the

MAIN RUN screen with the new resolution setting active or [ESC] to make no changes.

The resolution setting is range specific. A resolution setting made in one range does NOT

affect other ranges.

The measured pressure resolution is fixed for altitude units at 1 m in meters and 1 ft in feet.

The maximum resolution setting is limited in AutoRange ranges that are less than 10% of the

Q-RPT default full scale.

3.4.3

<3STAB>

PURPOSE

To view and/or adjust the stability test that is the Ready/Not Ready criterion for the active

RPT and range.

See Section 3.2.1 Pressure Ready/Not Ready Indication.

PRINCIPLE

RPM4 continuously monitors the rate of change of pressure measured by the active RPT and

range and compares this rate to the stability limit to make a Ready/Not Ready determination

(see Section 3.2.1 Pressure Ready/Not Ready Indication). The stability function allows the

stability limit to be adjusted by the user to increase or decrease the stability required for a

Ready condition to occur.

The default stability limit is + 0.005% FS of the active range.

The stability limit is separate and different from the Rate DISPLAY function (see Section

3.3.6.2) which allows the current rate of change of pressure to be displayed.

Page 54

3. OPERATION

OPERATION

Stability:

0.020 Pa

To access the stability setting adjustment, press

[SETUP], <3stab>. The display is:

Edit the desired stability limit setting if desired. [ENT] activates the stability limit for the active

range and returns to the main run screen Press [ESC] to return to the MAIN RUN screen

with no change to the stability limit.

The stability setting is range specific. A stability setting made in one range does NOT

affect other ranges.

3.4.4

<4UL> (UPPER LIMIT)

PURPOSE

To set the upper and lower pressure limit values for a pressure range and measurement mode.

PRINCIPLE

The UPPER LIMIT function provides the user with settable pressure limits at which an alarm

sounds. Absolute and gauge measurement modes (see Section 3.3.3, PRINCIPLE) have

upper limits only. Negative gauge mode and the BA100K also have a lower limit.

When the limit is reached, RPM4’s beeper sounds intermittently as long as pressure is

outside the limit.

The UPPER LIMIT function has two purposes. First, when UL is set to its default value, it serves

as a warning that the maximum pressure of the active range (and lower pressure in negative

gauge mode) is about to be exceeded. Second, UL can be set by the user to a value other

than the default value to provide an alarm that a specific pressure limit has been exceeded.

This feature is often used to help protect an external device or system on which RPM4 is

being used to measure pressure. For example, it might be set just over the full scale of a

device under test (DUT) that is being calibrated. Note that using AutoRange automatically

sets the UL to just above the AutoRange full scale (see Section 3.3.4).

The default upper limit is 105 % of AutoRange span or 102 % of Q-RPT default (maximum)

range, whichever is lower. The default lower limit (negative gauge mode only ) is – 110 kPa

(- 16 psi), except with the BG15K Q-RPT in which the default lower limit is the negative

equivalent of the upper limit. The default lower limit of the BA100K Q-RPT is 66 kPa (9.6 psi).

In parallel measurement mode (see Section 3.5.7.2), the default and maximum UL is the

UL of the Lo Q-RPT.

In differential measurement mode (see Section 3.3.3.1), UL has upper and lower limits.

The default upper differential UL is the maximum pressure of the Hi Q-RTP. The default lower

UL is the negative value of the upper limit.

In differential measurement mode, the ULs on the Lo Q-RPT and Hi Q-RPT default range are

also active so that line pressure (Lo Q-RPT) and total pressure (Hi Q-RPT) upper limit can be

set and monitored in addition to a differential limit.

Page 55

RPM4™ OPERATION AND MAINTENANCE MANUAL

OPERATION

To view or edit upper and lower limits press [SETUP], <4UL>.

If the current measurement mode is absolute or gauge, there is an upper limit only.

The display is:

Upper limit:

204.000 kPa a

1. Entry field for upper limit value in active pressure unit of

measure and measurement mode.

Edit the upper limit value as desired. The maximum upper limit is 105 % of span in an

AutoRange range or 102 % of default Q-RPT full scale, whichever is smaller. Press [ENT] to

return to the MAIN RUN screen with the new upper limit active. Press [ESC] to return to the

MAIN RUN screen with no change to the upper limit.

If the current measurement mode is negative gauge, there is an upper limit and a lower limit.

The display is:

1. Entry field for upper limit value.

Upper: 104.00

2. Entry field for lower limit value and active range pressure unit

of measure and measurement mode indication.

Lower:-110.00 kPa g

Edit the upper and lower limit values as desired. Use the cursor control keys to move

between the two edit fields. The lower limit must be a negative value. Press [ENT] to return

to the MAIN RUN screen with the new upper and/or lower limit active. Press [ESC] to return

to the MAIN RUN screen with no change to the limits.

When the upper or lower limit has been exceeded, the display of current pressure flashes

and a buzzer sounds for 3 seconds on/2 seconds off intervals. Change the pressure applied

to RPM4 so that it is within the upper and/or lower limit to return to normal operation.

Upper limit values are specific to each range and measurement mode. Be careful not to

assume that the upper limit set in one measurement mode will apply to the other.

For example, if you change the upper limit in gauge mode, the upper limit will not be

changed in negative gauge mode.

Upper limits are always specified and displayed in the current pressure unit except for

altitude units. When in altitude units, upper limits are expressed in kPa if the altitude

unit is meters (m) and psi if the altitude unit is feet (ft).

In Hi Q-PRT differential mode (see Section 3.3.3.1) there are two UL values for the Hi Q-

RPT. One is the upper and lower limts for differential pressure, with a default value equal

to the span of the Lo RPT. The other is the UL on the base mode of the Hi Q-RPT DF

range to monitor the maximum pressure on the Hi Q-RPT. In differential mode, the Lo Q-

RPT UL is also active to provide monitoring of the differential mode line pressure.

Page 56

3. OPERATION

3.4.4.1

OVER PRESSURE FUNCTION

In addition to the UL function, RPM4 has an over pressure function.

The over pressure function executes when a Q-RPT measures a pressure that is

104 % of its default span. The G15K and BG15K Q-RPTs also have a negative

over pressure function. The negative over pressure function executes when the

Q-RPT measures a pressure less than - 17.5 kPa (- 2.3 psi).

The over pressure function causes the measured pressure display to flash.

If the Q-RPT module is equipped with SDS, SDS closes shutting off the TEST(-)

port (see Section 3.2.7). If the Q-RPT is a Gxxx or BGxxx, the TEST(+)/TEST(-)

bypass valve is opened (see Section 5.6, Figure 8). The overpressure function also

logs the time and date of the overpressure condition in both user and factory logs to

assist in incident diagnosis (see Section 3.5.7.5).

To recover from an overpressure condition, cycle RPM4 power. Be sure to

correct the condition that caused the overpressure before cycling power.

3.4.5

<5ATEST>

This feature not available at the time of this manual’s release. Check www.dhinstruments.com

for new RPM4 embedded software releases and manual updates.

3.5

[SPECIAL]

PURPOSE

[SPECIAL] accesses a menu of RPM4 functions and features that are less commonly used or not

normally used in regular operation.

OPERATION

1AutoZ 2remote 3head

Press [SPECIAL] from the MAIN RUN screen to access the

SPECIAL menu. The display is:

4SDS 5prefs 6Punit

7intern 8cal 9reset

Some screens, such as the SPECIAL menu, go beyond the two lines provided by the display. This is

indicated by a flashing arrow in the second line of the display. Press the cursor control keys to move the

cursor to access the lines that are not visible or directly enter the number of the hidden menu choice if you

know it.

SPECIAL menu choices include:

<1AutoZ>

<2remote>

Manage AutoZero function for the active Q-RPT (see Section 3.5.1).

View and edit COM port (RS-232) and IEEE-488 interface settings. Select remote syntax

style (see Section 3.5.2).

<3head>

<4SDS>

<5prefs>

Set HEAD function fluid and height unit of measure (see Section 3.5.3).

To view and set the ON/OFF and OPEN/CLOSED status of SDS for all Q-RPTs.

View and set screen saver time, keypad sound frequency, unit ID number, time/date,

security protection level (see Section 3.5.5).

<6Punit>

<7intern>

Customize the [UNIT] key pressure unit of measure selections (See section 3.5.6).

Access internal functions including on-board barometer viewing, read rate adjustment, parallel

measurement mode ON/OFF, direct control of Lo Vent valve(s), incident log viewing (see

Section 3.5.7).

<8cal>

View and adjust RPM4, Q-RPT and barometer calibration coefficients (see Sections 3.5.8, 5.2, 5.3).

Access RPM4’s various reset functions (see Section 3.5.9).

<9reset>

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RPM4™ OPERATION AND MAINTENANCE MANUAL

3.5.1

<1AUTOZ>

PURPOSE

To offset the RPM4 Q-RPT(s) readings relative to a reference value in order to compensate

for possible changes in Q-RPT zero between full recalibrations. In differential measurement

mode, to compensate for the difference between the reading of the Hi and Lo Q-RPTs at the

“line pressure” at which differential measurements are made.

To assure operation within measurement uncertainty specifications (see Section 1.2.2), it is

recommended that AutoZ be run (the value of P_offsetupdated) whenever vented in gauge mode,

whenever the line pressure is changed in differential mode and at least every 30 days or when

RPM4 has been exposed to temperature changes exceeding 15 ºC (36 ºF) in absolute mode.

PRINCIPLE

AutoZ Purpose and Principle

The main component of the change over time of the RPM4 Q-RPTs is change in zero or

offset, independent of span. Offsetting or “rezeroing” RPM4 Q-RPTs relative to a reference

between recalibrations allows measurement uncertainty specifications to be maintained with

less frequent full calibrations. AutoZ is also used to compensate for the difference between

the Hi and Lo Q-RPT at the “line pressure” at which differential measurements are made.

The RPM4 AutoZero function (AutoZ) provides full on-board support for the rezeroing

process to simplify its application by the user.

The AutoZero function uses three values:

1. P_std,0

The pressure value indicated by the AutoZ reference, the device that is acting as

the reference relative to which to offset the RPM4 Q-RPT.

For Axxx (absolute) Q-RPTs in absolute measurement mode, the pressure at which

AutoZ is performed is normally atmospheric pressure and the P_std,0value can be supplied

a) by manual entry, b) automatically from a DHI RPMx connected to RPM4 COM2

communications port, or c) automatically from an Axxx Lo Q-RPT if one is present in the

RPM4.

For Gxxx or BGxxx (gauge) Q-RPTs or Axxx (absolute) Q-RPTs in gauge measurement

mode, P_std,0is always zero (atmospheric pressure) which is supplied by definition when

the Q-RPT is vented to atmosphere.

For RPM4s with two Q-RPTs of the same type (Axxx, Gxxx, BGxxx) with the Hi Q-RPT in

differential measurement mode, P_std,0is the pressure indicated by the Lo Q-RPT when

the Hi and Lo Q-RPTs are connected to a common pressure.

2. P_u,0:

The pressure reading of the Q-RPT, with no AutoZ offset, at the time AutoZ is

performed.

3. P_offset,G, P_offset,Aand P_offset,D: The difference between the reading of the Q-RPT with no

AutoZ offset (P_u,0) and the indication of the AutoZ reference (P_std,0) for gauge (_G),

absolute(_A) or differential (_D) measurement mode:

P_offset= P_u,0- P_std,0

P_offsetrepresents the difference between the Q-RPT reading (P_u,0) and the AutoZ standard

(P_std,0). The AutoZ function manages the determination, storage and application of P_offsetto

correct the zero offset in absolute, gauge and differential measurement modes.

When the Q-RPT is calibrated, P_offsetis set to zero. P_offsetis then redetermined at regular

intervals using the AutoZ function. The most recent value of P_offsetis applied to the Q-RPT

reading to correct for change in zero.

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3. OPERATION

The AutoZ function can be turned ON and OFF. Table 7 summarizes the effect of AutoZ ON

and OFF for the three Q-RPT types in different measurement modes.

AutoZ in absolute measurement mode with an Axxx Q-RPT

Q-RPTs with the designation Axxx are intrinsically absolute. They have an evacuated and

sealed reference. Axxx Q-RPTs can measure absolute pressure (difference from vacuum).

In absolute measurement mode, the source of P_std,0must be an absolute pressure, nominally

atmospheric pressure, with uncertainty significantly better than that of the Q-RPT that is

being AutoZeroed. For higher range Q-RPTs, this is easily accomplished with a variety of

digital barometers or with a Lo Q-RPT in the RPM4. For lower range Q-RPTs, a piston gauge or

other standard may be required to provide P_std,0with low enough uncertainty.

When using an Axxx (absolute) Q-RPT in absolute measurement mode, with AutoZ ON,

absolute pressure is calculated as:

P_abs= P_u- P_offset,A

In absolute measurement mode, running the AutoZ function to update the AutoZ value

(P_offset,A), is initiated by the operator using [AutoZ].

AutoZ in gauge and negative gauge measurement modes with an Axxx Q-RPT,

dynamic compensation for atmospheric pressure

Q-RPTs with the designation Axxx are intrinsically absolute but they are also used in gauge

and negative gauge measurement modes (difference from atmosphere) (see Section 3.3.3,

PRINCIPLE). Gauge measurement mode is achieved by subtracting the value of

atmospheric pressure from the Q-RPT’s absolute reading using AutoZ and by dynamically

compensating for changes in atmospheric pressure between opportunities for AutoZ to

execute (see Section 3.2.2).

In gauge measurement modes on an Axxx Q-RPT, the value of P_std,0is always zero gauge

pressure. Zero gauge pressure, by definition, is applied to the Q-RPT when it is vented to

atmosphere. In gauge measurement modes, AutoZ is run when initiated by the operator

pressing [AutoZ] when the RPM4 is vented. This assures regular updating of the P_offset,G

value corresponding to atmospheric pressure. Gauge pressure is the measured absolute

pressure, P_u, minus P_offset,G

P_gauge= P_u- P_offset,G

When AutoZ is ON, dynamic compensation for atmospheric pressure is also applied to

compensate for changes in atmospheric pressure as measured by a barometer (ΔP_atm) between

AutoZ updates (see Section 3.2.2). The measured gauge pressure is calculated using ΔP_atm

to correct the value of P_offset.G

P_gauge= P_u- P_offset.G- ΔP_atm

In gauge measurement mode on an Axxx RPT, running the AutoZ function to update the

value of P_atm,0, is initiated by the operator using [AutoZ]. Updating of ΔP_atmoccurs

automatically and continuously.

When gauge or negative gauge mode is first activated on an Axxx Q-RPT, the value of

P_offset.Gsubtracted from the absolute pressure reading to achieve gauge pressure is

standard atmosphere of 101.325 kPa. This can cause a large zero error when gauge mode

is activated if atmospheric pressure is significantly different from standard atmospheric

pressure. When gauge mode is activated, always press [AutoZ] to run AutoZ and obtain

an actual value of P_offset.G

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RPM4™ OPERATION AND MAINTENANCE MANUAL

AutoZ in gauge measurement mode with a Gxxx or BGxxx Q-RPT

Q-RPTs with the designation Gxxx or BGxxx are intrinsically gauge. They have an atmospheric

(TEST(-)) reference port and measure gauge pressure (difference from atmosphere).

In gauge measurement mode the value of P_std,0is always zero gauge pressure. Zero gauge

pressure, by definition, is applied to the Q-RPT when it is vented to atmosphere.

When using a Gxxx Q-RPT in gauge measurement mode, with AutoZ ON, gauge pressure is

calculated as:

P_gauge= P_u- P_offset,G

In gauge measurement modes, AutoZ is run when initiated by the operator pressing [AutoZ]

when the RPM4 is vented. This assures the regular automated updating of the P_offset,Gvalue.

AutoZ in differential measurement mode

RPM4s with two Q-RPTs of the same type (Axxx, Gxxx, BGxxx) support differential

measurement mode (see Section 3.3.3.1) in which the measured pressure is the difference

between the pressure measured by the Hi Q-RPT and the Lo Q-RPT (Hi – Lo).

In differential measurement mode, the purpose of AutoZ is to compensate for the offset

between the Hi and Lo Q-RPT indications at the “line pressure” at which the differential

pressure is being measured. The value of P_std,0is the pressure indicated by the Lo Q-RPT at

the time of AutoZ.

When using an RPM4 with two Q-RPTs in differential measurement mode, with AutoZ ON,

differential pressure is calculated as:

P_differential= P_Hi- P_Lo- P_offset,D

In differential measurement mode, AutoZ is run when initiated by the operator pressing

[AutoZ] when both Q-RPTs of the RPM4 are connected to a common pressure..

AutoZ ON/OFF

The AutoZ function can be turned ON and OFF, separately for gauge, absolute and

differential measurement modes. Table 7 summarizes the effect of AutoZ ON and OFF.

Table 7. AutoZ ON and OFF

AutoZ

ROUTINE

RUNS

Q-RPT

TYPE

MEASUREMENT

MODE

AutoZ

STATUS

P_offset

APPLIED

ΔP_atm

APPLIED

When initiated

by operator

YES

Absolute

Not Applicable

OFF

Not available

Axxx

YES

When initiated

by operator

Gauge or

negative gauge

YES

OFF

When initiated

by operator

Gxxx

BGxxx

OFF

YES

Gauge or

negative gauge

Not Applicable

Not available

When initiated

by operator

Any, Hi Q-RPT

in dual Q-RPT

RPM4

YES

Differential

Not available

OFF

Recommendations for the Use of the AutoZ Function

The AutoZ function provides a powerful and easy to use tool for improving the stability over

time of RPM4 Q-RPTs and maximizing the recalibration interval by compensating for change

in zero between full recalibrations. In differential measurement mode, it minimizes the

uncertainty in the differential pressure due to the offset between the Hi and Lo Q-RPTs at the

Page 60

3. OPERATION

“line pressure”. The following simple recommendations will help assure that you use this

feature to best advantage.

•

In gauge and differential measurement mode: Always leave AutoZ ON when

operating.

In absolute measurement mode: Always leave AutoZ ON when operating if the AutoZ

routine has been run regularly using a valid atmospheric reference.

To assure operation within measurement uncertainty specifications (see Section 1.2.2),

run AutoZ whenever vented in gauge mode, whenever the line pressure is changed in

differential mode and at least every 30 days or when RPM4 has been exposed to

temperature changes exceeding 15 ºC (36 ºF) in absolute mode.

•

In absolute measurement mode:

Run AutoZ only when a reference whose

measurement uncertainty is known to be significantly better than that of the Q-RPT to be

AutoZeroed is available. Keep range ratios in mind when comparing uncertainty.

A ± 0.01 % FS barometer is roughly 10 times better than an ± 0.01 % 1 MPa (150 psi)

Q-RPT because the Q-RPT/barometer pressure ratio is 10:1. The measurement

uncertainty comparison should be made at 30 % of span for both standard class and

premium class Q-RPTs. Though it may not be practical and generally is not necessary,

the best possible reference with which to run AutoZ in absolute measurement mode is a

gas operated piston gauge (such as a DHI PG7601) applying atmospheric pressure to

the RPM4 test port. The best day to day reference is a properly calibrated DHI RPM4

with a BA100K Q-RPT interfaced directly as an external device to the RPM4 COM2 port.

•

In absolute measurement modes: Allow the RPM4 to stabilize at atmospheric pressure

and ambient temperature for 10 to 15 minutes before running AutoZ.

OPERATION

The AutoZ function and values are Q-RPT AND measurement mode (gauge/negative gauge

or absolute) specific.

To RUN the AutoZ routine that rezeroes the Q-RPT, use [AutoZ] (see Section 3.3.9).

To access the RPM4 AutoZ function press [SPECIAL], <1AutoZ>. The display is:

1. Active Q-RPT designator.

2. Indication of active measurement mode (<abs> for absolute,

1off 2view

3edit

<gage> for gauge and negative gauge, <dif> for differential).

abs ON

3. Indication of whether AutoZ is currently ON or OFF for this

Q-RPT and measurement mode.

Select <1off> (or <1on>) to change the AutoZ status for the current Q-RPT and

measurement mode from ON to OFF or vice versa.

AutoZ ON is indicated by a <z> in the MAIN RUN screen, top line, fourth character from

the right. When AutoZ is OFF, the character is blank.

Select <2view> to view the current value of P_offsetfor the active Q-RPT and measurement mode.

P_offsetshould be zero when the RPM4 is new or has just been calibrated. P_offsetshould be

roughly equal to atmospheric pressure for an Axxx (absolute) Q-RPT operating in gauge mode.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

Select <3edit> to edit the value of P_offsetfor the active Q-RPT and measurement mode

(see Section 3.5.1.1).

The value of P_offsetis always displayed and entered in Pascal (Pa).

3.5.1.1

EDIT AUTOZ

The edit AutoZ function should be used with great caution as entering

inappropriate values and turning ON AutoZ may result in out of tolerance

measurements. In normal operation, the value of the AutoZ offset, P_offset

should be changed by running AutoZ using [AutoZ] (seen Section 3.3.9).

Before editing P_offset, see Section 3.5.1, PRINCIPLE.

To edit the current P_offsetvalue for the active Q-RPT and measurement mode,

press [SPECIAL], <1AutoZ>, <3edit>. The display is:

1. Indication of active measurement mode

(<abs> for absolute, <gage> for gauge and

Poffset, Abs

8.4 Pa

negative gauge, <dif> for differential).

2. Active Q-RPT for which P_offsetis being viewed.

3. Edit field for value of P_offset

Edit P_offsetas desired and press [ENT] to activate the new value. Press [ESC] to

abandon changes.

The value of P_offsetis always displayed and entered in Pascal (Pa).

3.5.2

<2REMOTE>

PURPOSE

To configure the RPM4 COM1, COM2 and IEEE-488 (GPIB) communication ports. To test COM1

and COM2 communications. To select the remote programming communications format.

PRINCIPLE

The RPM4 has two RS-232 communications ports referred to as COM1 and COM2 and a

single IEEE-488 (GPIB) port. COM1 or the IEEE-488 port is for communicating with a host

computer (see Section 4), and COM2 is reserved for communicating with an external device

(e.g. an RPMx, a multimeter, etc.). These ports’ settings can be viewed and changed using

[SPECIAL], <2remote>.

RPM4 has two remote communications formats, classic and ENHANCED (see Section 4.3).

Which of these is active can be selected.

A self test is supplied for RS-232 communications. The self test allows verification that the

RPM4 RS232 ports (COM1 and COM2) are operating properly and that a valid interface

cable is being used.

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3. OPERATION

OPERATION

To access the communications settings, press [SPECIAL], <2Remote>.

•

Select <1COM1> to view and edit COM1 settings (see Section 3.5.2.1.).

Select <2COM2> to view and edit COM2 settings (see Section 3.5.2.1.).

Select <3IEEE> to view and edit IEEE-488 settings (see Section 3.5.2.2).

Select <4format> to select the remote communications command format (see Section 3.5.2.3).

Select <5RS232test> to run the COM1 and COM2 communications test (see Section 3.5.2.4).

3.5.2.1

<1COM1, 2COM2>

The COMx ports can be set for specific communications settings. The settings

are baud rate, parity, data bits and stop bits. The available options are:

Baud

300, 600, 1 200, 2 400, 4 800, 9 600, 19 200, 28 800, 38 400

Parity

NONE, ODD or EVEN

Length

Stop Bit

7 or 8

1 or 2

The default is <2 400, E, 7,1> for both COM1 and COM2.

The user can also specify one or two termination characters as well as define

these characters. These are referred to as “Term1” and “Term2”. These define

the characters that mark the end of commands that are sent to the RPM4. The

RPM4 looks for an ASCII(13) (carriage return) to terminate a received command

but responds with both and ASCII(13) (carriage return) and an ASCII(10) (line

feed). There are no other options.

3.5.2.2

<3IEEE-488>

The IEEE-488 port’s primary address can be set from 1 to 31 in this screen.

The factory default value is 10. Secondary addressing is not used or supported.

This address must not conflict with the address of any other device on the same

IEEE-488 bus.

The receiving terminating character must be a line feed and EOI. Carriage returns

are ignored if received. The RPM4 sends a line feed and asserts the EOI line to

terminate a reply. These settings are fixed to agree with IEEE Std. 488.2. If you

change the address, the IEEE interface will reset (PON) and become idle.

3.5.2.3

<4FORMAT>

The RPM4 has two different syntax formats available for the remote program

commands.

The classic remote command format is highly intuitive and conforms with

previous DHI PPC and RPM products.

The enhanced remote command format generally uses the same commands as

the classic format, but in addition it follows the syntax, format, and status

reporting features of IEEE Std 488.2.

The details of each format are covered in Section 4.3.

[SPECIAL], <2remote>, <4format> allows the remote program command

syntax to be selected. The cursor is on the active format. Select <1classic> or

<2enhanced> as desired.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

3.5.2.4

<5RS232 SELF-TEST>

The RS232 self-test is provided to check the RPM4 COM ports and the interface

cable independently of an external device or computer.

If you are having difficulty communicating with RPM4 from a host computer

using RS232, the RS232 self test can help establish that the RPM4 COM1 port

you are trying to communicate with and the interface cable you are using are good.

To run a self test of the RS232 ports (COM1 and COM2), press [SPECIAL],

<2remote>, <5RS232test>.

The display prompts you to connect COM1 to COM2 using a standard pin-to-pin

DB-9F to DB-9M RS232 cable (see Section 4.2.1.1, 4.2.1.3).

Once the cable has been installed, press [ENT] to run the self-test. The test is first

executed in the COM1→COM2 direction and then in the COM2→COM1 direction.

If the COM1→COM2 test passes:

<PASSED> displays briefly and the test

proceeds to COM2→COM1.

If COM2→COM1 passes:

<PASSED> is displayed briefly followed

by the conclusion, <The RS232 test has

PASSED>.

If a test fails:

Execution is suspended until [ENT] is

pressed.

The RPM4 RS232 test can fail for three reasons:

1. The RS232 cable being used is incorrect (Section 4.2.1.1, 4.2.1.3 for

information on the correct cable).

2. COM1 and COM2 do NOT have the same serial communications settings

and therefore cannot communicate together (see Section 3.5.2.1 to set

the COM ports).

3. COM1 or COM2 is defective.

The reason for failed communications is almost always a cable or incorrect

RS232 interface settings. Be sure that these are correct before concluding

that a COM port is defective.

3.5.3

<3HEAD>

PURPOSE

To view or change the properties of the HEAD function (see Section 3.3.7) including the unit of

measure of length for head height entry and the test fluid type and species for density calculations.

OPERATION

From the MAIN RUN screen, pressure [SPECIAL], <3Head>.

Select the desired height unit of measure and press [ENT].

Select <1gas> or <2liqud> depending on the pressurized medium between the RPM4 and

the height at which pressure is to be calculated. Select the gas or liquid species. The liquid

selection <3User>, is to create a custom liquid with a user entered density.

Use [HEAD] to set a head height if desired.

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3. OPERATION

3.5.4

<4SDS>

PURPOSE

To open and close SDS temporarily for the Hi or Lo Q-RPT or to turn the SDS function ON

and OFF full time for the Hi or Lo Q-RPT.

See Section 3.2.7 for complete information on RPM4’s SDS (Self Defense System) feature.

PRINCIPLE

SDS is a self defense system to protect RPM4 Q-RPTs from overpressure (see Section 3.2.7).

Normally, opening and closing SDS is performed automatically by the RPM4 or by the

operator using the [SDS] key.

[SPECIAL], <4SDS> gives further control over the SDS function.

This includes:

a) the possibility of temporarily opening or closing SDS on either the Hi or Lo Q-RPT (see

Section 3.5.4.1), and; b) turning OFF SDS so that it is open full time and RPM4 can be

operated as if SDS were not installed (see Section 3.5.4.2).

The temporary opening or closing of SDS allows the SDS open/closed state to be set

immediately to the desired state. Following the change, normal automated operation of SDS

and control using the [SDS] key is still valid. This function is often used to open SDS on the

inactive Q-RPT in PRM4s with dual Q-RPTs.

Setting the SDS function to full time OFF eliminates the SDS function completely until is set

to full time ON again.

3.5.4.1

<1TEMP OPEN/CLOSE>

OPERATION

See Section 3.2.7 for complete information on RPM4’s SDS (Self Defense

System) feature.

To temporarily open or close the SDS of the Hi or Lo Q-RPT press [SPECIAL],

<4SDS>, <1temp open/close>. If the RPM4 has two Q-RPTs and both have

SDS, the Q-RPT must then be selected. The next display is:

The cursor is on the current state of SDS for the

designated Q-RPT. Select <1close> to close

SDS temporary:

1close 2open

SDS or <2open> to open SDS and return to the

MAIN RUN screen. [ESC] to return without

making changes.

If <2open> is selected and SDS for the Q-RPT is not already open, the SDS

opening screen with indication of the maximum pressure of the Q-RPT is displayed.

This is the same screen used when opening SDS using the [SDS] key (see

Section 3.3.8). Check that the pressure applied to the Q-RPT module TEST(+)

port does not exceed the Pmax! value before confirming that SDS should be opened.

Opening SDS with a pressure greater than Pmax! applied to the test port

may cause overpressure damage to the Q-RPT.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

3.5.4.2

<2FULL TIME ON/OFF>

OPERATION

See Section 3.2.7 for complete information on RPM4’s SDS (Self Defense

System) feature.

Turning SDS “full time OFF” for a Q-RPT module eliminates normal SDS

operation so that the Q-RPT module TEST(+) port remains open. However,

the SDS overpressure function (see Section 3.4.4.1) remains active.

To turn SDS full time ON or OFF for a Q-RPT module, press [SPECIAL],

<4SDS>, <2full time on/off >. If the RPM4 has two Q-RPTs and both have SDS,

the Q-RPT must then be selected. The next display is:

The cursor is on the current state of SDS for the

designated Q-RPT. Select <1on> to set SDS for

normal operation and return to the main run SDS full time:

1on 2off

screen. Select <2off> to open SDS permanently

so operation is as if SDS were not installed.

[ESC] to return without making changes.

If <2off> is selected and SDS for the Q-RPT is not already open, the SDS opening

screen with indication of the maximum pressure of the Q-RPT is displayed. This is

the same screen used when opening SDS using the [SDS] key (see Section

3.3.8). Check that the pressure applied to the Q-RPT module TEST(+) port does

not exceed the Pmax! value before confirming that SDS should be opened.

Opening SDS with a pressure greater than Pmax! applied to the test port

may cause overpressure damage to the Q-RPT.

3.5.5

<5PREFS>

PURPOSE

To access a menu of RPM4 operational preferences and functions.

OPERATION

1ScrSvr 2sound 3time

4ID 5level

To access the PREFS menu press [SPECIAL],

<5prefs>. The display is:

The PREFS menu includes:

<1ScrSvr> View and change the screen saver activation time (see Section 3.5.5.1).

<2sound>

<3time>

<4ID>

View and change the keypress sounds (see Section 3.5.5.2).

View and edit the internal time and date settings (see Section 3.5.5.3).

View the RPM4 serial number (SN) and view or edit the ID number

(see Section 3.5.5.4).

<4level>

View and set user security level and/or password (see Section 3.5.5.5).

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3. OPERATION

3.5.5.1

<1SCRSVR>

PURPOSE

To adjust the idle time after which RPM4’s SCREEN SAVER activates.

PRINCIPLE

RPM4 has a SCREEN SAVER function which causes the display to dim after a

front panel key is NOT pressed for a certain amount of time. The default is for the

screen saver to activate after 10 idle minutes. The screen saver activation time

can be adjusted by the user or screen saving can be completely eliminated.

Setting screen saver time to zero eliminates the SCREEN SAVER function so

that the display permanently remains at full brightness.

OPERATION

To access the SCREEN SAVER function, press [SPECIAL], <5prefs>,

<1ScrSav>. Edit, in minutes, the idle time after which screen saver will activate

to dim the screen. Set the time to zero to eliminate the SCREEN SAVER function.

3.5.5.2

<2SOUND>

PURPOSE

To adjust or suppress the RPM4 valid key press sound.

PRINCIPLE

RPM4 provides audible feedback by a brief “beep” when a valid key press is

made. The tone frequency of this beep may be selected from three choices or it

may be completely suppressed. Invalid key presses are indicated by a

descending two tone “blurp” which cannot be suppressed.

OPERATION

To access the keypad sound adjustment function press [SPECIAL], <5prefs>,

<2sound>.

Select between <2lo>, <3mid> or <4hi> to adjust the valid key press tone frequency.

Select <1none> to suppress the valid key press tone.

The sound function only affects the valid key press tone. The invalid key

press tone and other RPM4 sounds cannot be adjusted or suppressed.

3.5.5.3

<3TIME>

PURPOSE

To view and edit the RPM4 internal time and date settings.

OPERATION

access the

TIME

function

Edit: 1time 2date

press [SPECIAL], <5prefs>, <3time>.

08:32:11 am 20030125

The display is:

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RPM4™ OPERATION AND MAINTENANCE MANUAL

Select <1time> to edit the time. Edit hours, then minutes, then am/pm by

pressing [ENT] after each entry. Seconds go to zero when minutes are entered.

This can be used to synchronize the time with a time standard.

Select <2date> to edit the date. The date must be specified in YYYYMMDD format.

The RPM4 date and time are set to United States Mountain Standard Time

in the final test and inspection process at the factory. If desired, use the

TIME and DATE function to set your local time and date.

3.5.5.4

<4ID>

PURPOSE

To view or edit the RPM4 user ID and to view the RPM4 serial number.

OPERATION

To access the ID function press [SPECIAL] and select <5prefs>, <2ID>.

Select <1view> to view the current ID.

Select <2edit> to edit the ID.

The ID has twelve characters. When the edit screen is opened, the cursor is on

the first character. Numerical values can be entered directly from the keypad. In

addition, the cursor control keys can be used to toggle through a list of available

alphanumeric characters. Holding the key slews through the characters.

Character order going up is: blank space, symbols, lower case letters, upper

case letters, numbers. After selecting a character, press [ENT] to activate it and

move to the next character field.

When a character is selected the cursor moves to the next character. To leave a

blank character, press [ENT] with the field for that character blank. Use this for

the trailing characters if the ID being entered is less than twelve characters.

After the last of the twelve characters has been entered, the <Save ID?> option is offered.

Select <1no> to return to the ID edit screen. Select <2yes> to save the edited ID.

The ID can be set remotely from a computer which is quite a bit more

convenient than entering characters from the keyboard (see Section 4.4.4,

ID command). The ID is not cleared or reset by any RESET function

(see Section 3.5.9).

3.5.5.5

<5LEVEL> (SECURITY)

PURPOSE

To set user protection levels to restrict access to certain functions and to edit the

password required for changing user levels.

PRINCIPLE

RPM4’s front panel user interface provides the means to access all RPM4 user

defined data, settings and functions including calibration data. Inadvertent,

uninformed or unauthorized altering or deleting of data, settings and functions

could require extensive reconfiguration by the user and might cause invalid

readings and behavior. For these reasons, depending upon the application in

which RPM4 is being used, it may be desirable to restrict access to some

functions. The user level function provides a means of restricting access to certain

functions. Four different levels of security are available.

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3. OPERATION

Access to changing security levels can be left open, or be protected by a password.

Security Levels

The security levels are structured to support typical operating environments as follows:

None

Low

This level is intended for use only by the system manager and/or

calibration facility. It allows access and editing in all areas including

critical metrological information.

Low security is designed to protect the specific metrological

information and SYSTEM DIAGNOSTIC AND MAINTENANCE

functions of the system against accidental alteration. It is intended for

an advanced operator performing many different tasks. Low security

is the default user level setting.

Medium

High

Medium security is designed to protect specific metrological

information in the system and to assure that the RPM4 is operated

using consistent operational parameters.

High security is designed to protect all operating parameters. It is

intended to minimize operator choices, for example to perform

repeated identical calibrations under consistent conditions.

RPM4 is delivered with the security level set at low to avoid inadvertent

altering of critical internal settings but with access to changing security

levels unrestricted. It is recommended that the low security level be

maintained at all times. If there is a risk of unauthorized changing of the

security level, changing authority should be password protected

(see OPERATION of this section).

The security levels are structured to support typical levels of operation as shown

in Table 8. Specifically, the security levels prevent execution of the functions

accessed by the key strokes marked by “•”:

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RPM4™ OPERATION AND MAINTENANCE MANUAL

Table 8. Security Levels

FUNCTION

LOW

MEDIUM

HIGH

[RANGE]

•

[ENT] (AutoTest)

[UNIT]

[MODE]

[AutoRange]

•

[LEAK CK]

[DISPLAY]

[HEAD]

[SDS]

[AutoZ] (in absolute mode)

[SETUP]

•

[SETUP], <1range>

[SETUP], <2res>

[SETUP], <4UL>

[SPECIAL]

•

[SPECIAL], <1AutoZ>

[SPECIAL], <1AutoZ>, <1on/1off>

[SPECIAL], <1AutoZ>, <3edit>

[SPECIAL], <2remote>

•

[SPECIAL], <2remote>, make changes

[SPECIAL], <3head>

•

[SPECIAL], <4SDS>

[SPECIAL], <5pref>, <1ScrSvr>

[SPECIAL], <5pref>, <2sound>

[SPECIAL], <5pref>, <3time>

[SPECIAL], <5pref>, <3time>, make changes

SPECIAL], <5pref>, <4ID>, <2edit>

[SPECIAL], <6Punit>

•

[SPECIAL], <7internal>

[SPECIAL], <7internal>, <3RPT2x>

[SPECIAL], <7interrnal>, <5log>, clear log

[SPECIAL], <8cal>

•

[SPECIAL], <8cal>, <2edit> under any selection

[SPECIAL], <4reset>

•

[SPECIAL], <4reset>, <4cal>

[SPECIAL], <4reset>, <5all>

Remote communications disabled

•

“•” indicates the function/menu is NOT accessible.

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3. OPERATION

OPERATION

RPM4 is delivered with no active password and access to the User Level menu is

open. The user level is set to <1Low>. User levels can be changed freely until a

password has been created.

access

the

LEVEL

function

1change user level

2edit password

press [SPECIAL], <5prefs>, <5level>.

The display is:

Restrictions: 1none

2low 3medium 4high

Selecting <1change user level> brings

up the restriction menu:

The cursor is on the current restriction level. Select a different level or

or [ESC] back to the MAIN RUN screen.

If no password is active, selecting

<2edit password> displays the user

password and allows it to be edited.

Password: pppppp

0 disables password

Once a password has been entered, the user level cannot be changed without

reentering the password.

Passwords can be up to six numbers in length and cannot start with a zero.

If <0> is entered, the password is made inactive and the user will not be required

to enter a password to access the user level menu. This condition, with a

security level of <2low>, is the factory default.

If there is an active password, the

RPM4 password entry screen appears.

The user must enter the user defined

password or the factory secondary

RPM4 SNnnnn-xx

Password: pppppp

password to proceed further:

The first field, <nnnn>, is the serial number of the RPM4, followed by a second field,

<xx>, that represents the number of times that a secondary password has been

used. The second field, <xx>, increments each time a secondary password is

used. The third field, <pppppp> is for user entry of the normal password.

The factory secondary password is available in case the user’s password has

been misplaced or forgotten. It can be obtained by contacting a DHI

Authorized Service Center (see Table 29). The factory secondary password

is different for all RPM4’s and changes each time it is used.

3.5.6

<6PUNIT>

PURPOSE

To customize the selection of pressure units of measure that are available in the [UNIT] key menu.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

PRINCIPLE

The [UNIT] function key makes available a choice of six default pressure units (US or SI units

depending on whether the RPM4 has been factory set as US or SI) (see Section 3.3.2).

RPM4 also supports many commonly used units other than those included in the default set up.

These units can be made available for active selection by customizing the UNIT function

using [SPECIAL], <6PresU>. This allows RPM4 to offer a very wide selection of units while

simplifying day to day operation. The typical user customizes the [UNIT] function key to

support his/her six most commonly used units.

OPERATION

To customize the [UNIT] function key, from the MAIN RUN screen press [SPECIAL],

<6PresU>. The display is:

1. Entry field to specify which unit position (1 to 6) of the [UNIT]

Set up unit #6

function key menu is to be changed.

Unit#6 1SI 2other

3altitude 4user

Enter the number of the unit position that you would

like to change. The display becomes:

Select the desired pressure unit category (SI units include units based on SI units such as

mmHg), then select the desired unit from the unit menu.

The units of measure available are listed in Table 9.

Table 9. UNIT Function - Available Units of Measure

<1SI>

<2OTHER>

<3ALTITUDE>

<4USER>

<1Pa>

<2hPa>

<1psi>

<2psf>

<1feet>

<2meters>

<3kPa>

<3inHg>

<4inWa>

<5kcm2>

<6Torr>

<7mTor>

<4MPa>

<5mbar>

<6bar>

<7mmHg>

<8mmWa>

If <4user> is selected, the user unit must be defined. The display is:

Define user unit:

1.000000 unit/Pa

1. Entry field.

Enter the number of user units per Pascal (Pa) in the entry field. Pressing [ENT] defines the

user unit and returns to the <Set up unit #n> screen.

The user defined unit label can be customized to any alphanumeric, four character label

using the remote command “UDU” (see Section 4.4.4).

See Section 7.2.1 for the pressure unit conversion factors used by RPM4.

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3. OPERATION

3.5.7

<7INTERNAL>

PURPOSE

To view, set, adjust, and maintain various aspects of RPM4’s internal operation.

OPERATION

1baro 2ReadRt 3RPT2x

4lo vnt 5log

To access the internal selections press [SPECIAL],

<7internal>. The display is:

The INTERNAL menu choices include:

<1baro>

View the real time output of the on-board barometer, if present (see Section

3.5.7.1).

<2ReadRt>

<3RPT2x>

Turn ON and OFF RPM4’s automated, rate of change dependent, reading

integration rate feature (see Section 3.5.7.2).

Enable and disable RPM4 parallel measurement mode in which two Q-RPT

modules are used to measure in parallel and their readings are averaged

(see Section 3.5.7.3).

<4lo vnt>

<5log>

Operate Q-RPT module Gxxx and BGxxx low VENT valve directly

(see Section 3.4.7.4).

View the RPM4 incident log (see Section 3.5.7.5).

3.5.7.1

<1BARO>

PURPOSE

To view the value of atmospheric pressure as measured by the RPM4 on-board

barometer.

There is no on-board barometer in RPM4’s that have Gxxx (gauge) internal

Q-RPTs only.

PRINCIPLE

RPM4’s that include an Axxx (absolute) and/or BGxxx (bi-directional gauge)

Q-RPT are equipped with a separate, on-board barometer. The atmospheric

pressure measurements made by the on-board barometer are used for dynamic

compensation of atmospheric pressure when using an Axxx Q-RPT to make gauge

pressure measurements (see Sections 3.3.3, PRINCIPLE and 3.2.2) and for static

pressure compensation when using a G15K or BG15K Q-RPT.

See Section 5.5, Figure 7 and Section 5.6, Figure 8 for a photo and

schematics showing the position of the on-board barometer in RPM4.

The on-board barometer is a low accuracy sensor used only for measuring

small changes in atmospheric pressure over short periods of time

(see Section 3.2.2) and for line pressure compensation when using a G15K or

BG15K Q-RPT. RPM4 measurement uncertainty does not depend on the

measurement uncertainty of the on-board barometer.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

OPERATION

RPM4’s that have only G100K or G200K Q-RPTs (no Axxx, G15K or BG15K)

are NOT equipped with an on-board barometer.

To view the current reading of the on-board barometer press [SPECIAL],

<7internal>, <1baro>. The display is in the active pressure unit of measure

(see Section 3.3.2). The display resolution is fixed to 0.01 Pa, or its equivalent.

3.5.7.2

<2READRT>

PURPOSE

To turn ON and OFF RPM4’s automated, rate of change dependent, reading

integration rate feature.

PRINCIPLE

To obtain maximum resolution from RPM4 Q-RPT pressure measurements, an

integration time of about 1.2 second per reading is used. In most situations,

maximum precision is needed when pressures are stable so a relatively slow

display update rate presents no disadvantage. However, when pressure is

changing quickly, more rapid pressure updates are usually more important than

obtaining maximum precision on individual readings. The RPM4 read rate

function automatically adjusts pressure measurement integration time depending

on the rate of change of pressure. When pressure is changing rapidly, reading

rate is increased. When pressure is evolving slowly, reading rate is decreased

and maximum precision is obtained.

When the automated read rate function is ON, three pressure rate of change

dependent read rates are used. The result is three display update rates:

Table 10. READRT - Display Update Rates

PRESSURE

RATE OF CHANGE

DISPLAY

UPDATE

> 3 % of range span/s

≈ 0.2 s

≈ 0.6 s

≈ 1.2 s

> 0.5 and < 3 % of range span/s

< 0.5 % of range span/s

For situations in which maximum reading precision is desired regardless of pressure

rate of change, the RPM4 automated read rate function can be turned OFF.

In this case, the reading rate is always the high resolution rate of about 1.2 readings

per second.

OPERATION

To turn the automated read rate function ON or OFF or check its current status,

press [SPECIAL], <7internal>, <3ReadRt>.

Auto read rate:

The display is:

1on 2off

The cursor is on the current selection.

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3. OPERATION

Selecting <1on> activates the automated reading rate and returns to the MAIN

RUN screen. Selecting <2off> turns OFF the automated reading rate and

returns to the MAIN RUN screen.

The default RPM4 condition is auto read rate ON.

Auto read rate ON/OFF is NOT Q-RPT or range specific. Turning auto read

rate ON or OFF in one range turns it ON or OFF for all RPM4 ranges.

3.5.7.3

<3RPT2X>

PURPOSE

To enable and disable the RPM4 parallel measurement mode in which two

Q-RPT modules are used to measure in parallel and their readings are averaged.

PRINCIPLE

RPM4s that have two Q-RPT modules of the same type (Axxx, Gxxx or BGxxx)

support parallel measurement mode. In this mode, both Q-RPTs are used to

measure the same pressure in parallel and their readings are averaged.

Parallel measurement mode sets up a third Q-RPT designated HL (combination

of Hi and Lo). The HL RPT can be selected by the [RANGE] function and

supports other RPM4 functions such as UNIT, MODE and DISPLAY.

When parallel measurement mode is set up, the resulting HL Q-RPT can be a

third Q-RPT in addition to the Hi and Lo RPTs. It is also possible to make the HL

Q-RPT the sole Q-RPT, suppressing the Hi and Lo Q-RPTs. This feature is used

when an RPM4 will always be used in parallel measurement mode and the

availability of the individual Hi and Lo Q-RPTs is not desired.

[SPECIAL], <7internal>, <3RPT2x> is used to set up or suppress parallel

measurement mode in RPM4s that support it.

In parallel measurement mode, the maximum pressure is the maximum

pressure of the Lo Q-RPT.

OPERATION

Parallel measurement mode is only available on RPM4s with two Q-RPTs of

the same type (Axxx, Gxxx, BGxxx).

To access the parallel measurement mode enable/disable function press

[SPECIAL], <7internal>, <3RPT2x>.

The cursor is on the number corresponding to the current setting.

Select <1off> to disable parallel measurement mode. This will eliminate the HL

Q-RPT.

Select <2on> to enable parallel measurement mode. This creates the HL

parallel mode Q-RPT. The Hi and Lo Q-RPTs are also still available.

Select <3on, w/ Hi & Lo RPT off> to enable parallel measurement mode and

disable access to the Hi and Lo Q-RPTs individually. This creates the HL

parallel mode Q-RPT and makes it the sole Q-RPT available for selection.

When using parallel measurement mode, if RPM4 detects an excessive

difference between the pressure measured by the Hi and Lo Q-RPTs, a warning

is given by rapid beeps for 8 seconds and displaying <Check RPT connection>.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

Operation returns to normal when the disagreement between the two Q-RPTs

returns to normal.

When using parallel measurement mode, the Hi and Lo Q-RPTs should be

connected IN PARALLEL to the pressure to be measured (both Q-RPTs

connected to the same pressure). The measured pressure indicated in

parallel measurement mode is the average of the Hi and Lo Q-RPTs.

3.5.7.4

<4LO VNT>

PURPOSE

To cause an RPM4’s Gxxx or BGxxx Q-RPT TEST(-) vent valve to stay open or

closed rather than open and close automatically.

This feature is active only when the active Q-RPT is a Gxxx (gauge) or

BGxxx (bi-directional gauge) Q-RPT.

PRINCIPLE

An RPM4 equipped with a Gxxx (gauge) or BGxxx (bi-directional gauge) Q-RPT has

a TEST(-) vent valve in its Q-RPT module (see Figure 8, Gxxx, BGxxx, Valve C).

The TEST(-) vent valve is used to open the TEST(-) port to atmosphere which

also connects the Q-RPT and the device or system under test low side to atmosphere.

In normal RPM4 operation, the TEST(-) valve is closed to isolate the low pressure

circuit from fluctuations in ambient pressure when the Q-RPT is being used to

measure pressure. It is open only when SDS is closed (see Section 3.2.7).

However, it may be desirable to open the TEST(-) port to atmosphere while

measuring pressure and/or without closing SDS. For example, this may be

necessary to assure that the pressure on the low side of the Q-RPT and the

system under test does not move too far away from atmosphere. [SPECIAL],

<7internal>, <4lo vnt> allows the TEST(-) vent valve to be set to be

permanently open, permanently closed or to operate in its default, automated

condition. It also allows the current status of the valve to be viewed.

OPERATION

The normal, default setting for the TEST(-) vent valve is <1auto> in which RPM4

automatically controls the valve based on current Q-RPT module operation.

Setting other than <1auto> should only be selected by advanced users.

To access the LO VNT function press [SPECIAL], <7internal>, <4lo vent>. If the

RPM4 does not have a Gxxx (gauge) or BGxxx (bi-directional gauge) Q-RPT, the

display is: <Available with Gxxx or BGxxx Q-RPT only>. If the RPM4 has

more than one Gxxx or BGxxx Q-RPTs, the Hi or Lo Q-RPT must be selected.

Test(-) vent:1auto

The next display is:

2open 3close 4view

Select <1auto> for the TEST(-) vent valve operation to be controlled automatically

by RPM4 based on current operation. This is the default and recommended setting.

Select <2open> to cause the TEST(-) valve to open and remain open regardless

of RPM4 operation until the setting is changed. If RPM4 detects a condition

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3. OPERATION

in which it determines there could be a risk of overpressure to the Q-RPT

by opening the TEST(-) vent valve, the message <Cannot open lo vent,

DP overpressure risk> is displayed. If this message is displayed, return to

normal operation, vent the RPM4 Q-RPT module and try again.

Select <3close> to cause the TEST(-) vent valve to close and remain closed

regardless of RPM4 operation until the setting is changed.

Select <4view> to view the current condition of the TEST(-) valve. The display

indicates whether current valve operation is controlled by the RPM4

(<Auto TEST(-) vent>) or has been set manually (<Manual TEST(-) vent>)

followed by the current valve status (<Open> or <Close>).

If the RPM4 is being used as an external device to a PPC3 pressure controller

(see Section 3.5.7.4), the Lo Vent setting may be changed from the PPC3

(see the PPC3 Operation and Maintenance Manual).

3.5.7.5

<5LOG>

PURPOSE

To view and/or clear the RPM4 event log.

PRINCIPLE

RPM4 records to a log each time one of the following events occurs:

•

Pmax! of an internal RPM4 Q-RPT or utility sensor is exceeded (see Section

3.4.4.1).

•

A memory fault occurs.

OPERATION

To view the event log press [SPECIAL], <9Log>.

Use [ ] and [ ] to move back and forth between older and newer log entries.

Each log entry has two screens, one with the event description and one with the

even time and date. Use [ ] and [ ] to toggle between the two screens. The

oldest logged event appears.

After the last log has been viewed, the option to clear the log, <1no>, <2yes> is

presented. Use <2yes> to remove all entries from the log. Use <1no> to

continue without altering the log.

To leave the log, use [ESC].

3.5.8

<8CAL>

PURPOSE

To calibrate the RPM4 Hi and Lo Q-RPTs and adjust the on-board barometer. These

functions are considered part of RPM4 maintenance and are covered in the maintenance

section of this manual (see Sections 5.2, 5.3).

PRINCIPLE

See Sections 5.2, 5.3.

OPERATION

See Sections 5.2, 5.3.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

3.5.9

<9RESET>

PURPOSE

To reset various RPM4 settings to default or factory values.

PRINCIPLE

RPM4 stores its user definable settings in non-volatile memory. The reset menu allows the

user to selectively or completely reset these settings to factory defaults. This clears any

settings that the user has made, and should be used only to restore the RPM4 to a known

state. RPM4 goes through its power up sequence after any type of reset is executed.

RPM4 reset functions will change current settings to factory defaults. These may include

settings vital to RPM4 operation and affecting the calibration of the quartz reference

pressure transducers (Q-RPTs). Reset functions should only be used by qualified personnel

with knowledge of reset consequences. Reset functions should never be used “experimentally”.

OPERATION

1sets 2units 3ATest

4cal 5all

To access the RESET menu, press [SPECIAL],

<9reset>. The display is:

RESET menu choices include:

<1set>

to reset general system operating parameters (see Section 3.5.9.1).

<2units> to reset unit of measure functions (see Section 3.5.9.2).

<3ATest> to reset AutoTest parameters and clear the AutoTest data log (see Section 3.5.9.3).

<4cal>

<5all>

to reset internal calibration coefficients and modes (see Section 3.5.9.4).

to reset all settings except ID and security password to factory default values

(see Section 3.5.9.5).

3.5.9.1

<1SETS>

PURPOSE

Sets most general operating parameters back to default values. Does not affect

calibration coefficients, remote interfaces or AutoRange ranges. The Reset – Sets

resets are itemized in Table 11.

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3. OPERATION

Table 11. Reset – Sets

RESET

[UNIT]

RESULT

SEE SECTION

Pressure unit of measure to first of the six available

3.3.2

Measurement mode to the native mode of the Q-RPT

Hi Q-RPT default range

3.3.3

3.3.1

3.3

[MODE]

[RANGE]

[HEAD]

0 cm height and Nitrogen medium

Stability Limit

Upper Limit

Resolution

AutoZ

0.005 % of Hi Q-RPT default range

3.4.3

3.4.4

3.4.2

3.5.1

Hi Q-RPT default range default value

0.001 % FS of Hi Q-RPT default range

AutoZ ON for all Q-RPTs and measurement modes.

Z_offsetvalue not affected

AutoZ

3.5.1, 3.2.2

3.3.5

_atm,0set to 101.325 kPa a

Leak Check

Screen Saver

Key Sounds

Lo Vnt

15 second run time. Clear logged results

10 minutes to activation

Medium tone valid key press sound

Automatic

3.5.5.1

3.5.5.2

3.5.7.4

3.5.7.2

ReadRate

Automatic

3.5.9.2

<2 UNITS>

PURPOSE

Sets the six pressure units available under the UNIT function to the SI or US

default selections depending on whether the RPM4 has been factory set for SI or US

(see Section 3.3.2).

Sets the user defined unit to 1.000/Pa (see Section 3.5.6).

Sets the reference temperature for inWa unit to 20°C.

3.5.9.3

<3ATEST>

•

PURPOSE

Resets Auto Tests to default characteristics (see Section 3.3.10).

Clears AutoTest data log (see Section 3.4.5).

•

3.5.9.4

<4 CAL>

PURPOSE

The Reset - Cal function will reset Q-RPT, utility sensor and barometer

calibration coefficients and settings and reset AutoZ values to zero. This

will change the RPM4 calibration and could cause it to make out of tolerance

measurements.

Clears all user values affecting the calibration of Q-RPTs and the on-board

barometer. The Reset – Cal resets are itemized in Table 12.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

Table 12. Reset – Cal

RESET

RESULT

SEE SECTION

All Q-RPT Calibration

Coefficients

PA to zero, PM to 1

5.2.1.1, 5.2.7

Axxx Q-RPT absolute and

negative gauge mode

5.2.5

5.3

On-board Barometer

Calibration Coefficients

PA to zero, PM to 1

Set all dates to 19800101

Calibration Date

AutoZ values

5.2.7, 5.3

3.5.1

Axxx Q-RPTs: All P_offsetvalues to zero for

absolute mode and 101325 Pa for gauge and

negative gauge modes

Gxxx, BGxxx Q-RPTs: All P_offsetvalues to zero

ON, all Q-RPTs, all measurement modes

AutoZ function

3.5.1

3.5.9.5

<5 ALL>

PURPOSE

The reset - all function clears and deletes large amounts of user defined

information including critical calibration data.

Combines all resets in one global reset command that clears the entire user

section of non-volatile memory except the ID function (see Section 3.5.5.4) and

the security level password (see Section 3.5.5.5) returning RPM4 to the

“as delivered” condition. The Reset – All resets are itemized in Table 13.

Table 13. Reset – All

RESET

Reset – Sets

RESULT

All the resets of Reset - Sets

All the resets of Reset - Units

All the resets of Reset - ATest

All the resets of Reset - Cal

SEE SECTION

3.5.9.1

Reset – Units

Reset – Atest

Reset – Cal

3.5.9.2

3.5.9.3

3.5.9.4

Remote Interfaces

COM1, COM2 and IEEE-R88 interfaces to

default settings.

3.5.2

Remote Communications

Level (Security)

Remote command format to Classic

Reset security level to low

Off

3.5.2.3

3.5.5.5

3.5.7.3

3.5.4.2

Parallel Measurement Mode

SDS

All SDS full time ON

Page 80

4. REMOTE OPERATION

4.1

OVERVIEW

Most of the RPM4 front panel functions can also be executed by commands from a remote computer.

The host computer can communicate to the RPM4 using the RPM4’s COM1 RS232 port or it’s IEEE-488 port.

Before writing test code using RPM4 remote commands, familiarize yourself with its operating principles

by reading Section 3 of this manual.

4.2

INTERFACING

Sending a program message to the RPM4 places it into remote mode. The remote indicator to the right

of the display window lights when the RPM4 is in remote mode. It also flickers when a program message

is received. The menus usually accessed from the front panel are locked out while in remote. The [ESC]

key returns the RPM4 to local operation unless the <REMOTE> program message, which locks out all

keypad operation, was sent to the unit.

4.2.1

RS232 INTERFACE

4.2.1.1

COM1

The RPM4 COM1 RS232 interface is located on the back of the unit. It is a 9-pin

male DB-9F connector configured as a DCE device. Data is transmitted out of

the unit using pin 2, and is received on pin 3. This allows a normal pin-to-pin

DB-9M to DB-9F RS232 cable to be used to connect to a DTE host.

Handshaking is not required or supported. The COM1 receive buffer is

80 bytes deep. If you overflow the buffer by sending too much data, the data will

be lost. Because of this, you must send a single program message at a time

and you must wait for the RPM4 to reply from the previous command before

issuing another command.

Table 14. COM1 Pin Designations and Connections

RPM4 COM1 DB-9F PIN DESIGNATIONS

PIN #

FUNCTION

DESCRIPTION

TxD

RxD

Grn

This pin transmits serial data from the RPM4 to the host.

This pin accepts serial data from the host computer.

This pin is the common return for the TxD and RxD signals.

IBM PC/XT DB-9F

CONNECTIONS

IBM PC/XT DB-9M TO RPM4 DB9F

CONNECTION

DB-25M

DB-9F

DB-9M

DB-9F

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RPM4™ OPERATION AND MAINTENANCE MANUAL

4.2.1.2

IEEE-488

The RPM4 IEEE-488 interface is located on the back of the unit. The physical

and electrical interface conforms to IEEE Std 488.1-1987 Subset E2 and IEEE

Std. 488.2-1992. You should not attempt to communicate with the IEEE-488

interface while using the COM1 interface. The IEEE-488 receive buffer is 250

bytes deep. If you attempt to overflow the buffer, the RPM4 will hold off release

of the NRFD handshake line until it can service and empty the receive buffer.

This keeps the buffer from overflowing. It is recommended that you check for

errors using the “ERR?” query after sending a group of non-query program

messages. When using queries, ensure that you wait for a reply to each query to

ensue proper operation and order of command execution. Replies to queries

remain in the reply queue until the host gets them, so they can “stack up”,

causing replies to appear out of sequence.

4.2.1.3

COM2

The RPM4 COM2 RS232 interface is located on the back of the unit. It can be used

to allow the host computer to communicate with another device through the RPM4.

This allows the user to use one host COM port to communicate with the RPM4 and

an additional RS232 device. Refer to the “#” remote program command for

details. When using the RPM4 as a reference for a PPC3, another RPM4 can be

connected to the first RPM4’s COM2 port, allowing the PPC3 to communicate

with both RPM4s (see Section 3.2.5).

COM2 is a 9-pin female DB-9F connector configured as a DTE device. Data is

transmitted out of the RPM4 using pin 3, and is received on pin 2. This allows a normal

pin-to-pin DB-9M to DB-9F RS232 cable to be used to connect to a DCE device.

Handshaking is not required or supported.

Table 15. COM2 DB-9F Pin Designations

PIN #

FUNCTION

DESCRIPTION

RxD

TxD

DTR

Grn

This pin transmits serial data from the RPM4 to a device.

This pin accepts serial data from the external device.

This pin is Data Terminal Ready (DTR) (held at + 5 V).

This pin is the common return for the TxD and RxD signals.

4.3

PROGRAMMING FORMATS

RPM4 supports two program message formats, the “classic”, and the “enhanced” formats. The user

must select which format to use. Selection can be accomplished from the front panel (see Section

3.5.2.3) or remotely using the “L2” or “L3” program message (see Section 4.4.4). The ”MSGFMT”

command can also be used to select the format, but is not recommended for new designs.

The main difference between the “classic” and “enhanced” formats is that when using the IEEE-488 interface,

a query operator “?” must be included in an enhanced command to yield a reply from the RPM4. When

using the COM1 port in classic or enhanced mode or using the IEEE-488 port in classic mode, every

command has a reply which the host must wait for before continuing. In addition, the enhanced message

format supports IEEE Std 488.2 syntax, format and status reporting. The default is the classic format.

In either format, it is recommended that you start out a command sequence with the “*CLS” command,

which clears all of the communication and error queues. The basic commands are similar for both the

classic and enhanced formats, but the usage, syntax, format and status reporting are different.

Many RPM4 classic and enhanced commands are common with PPC2+, PPCK+ and PPC3

Pressure/Controller Calibrators.

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4. REMOTE OPERATION

4.3.1

CLASSIC PROGRAM MESSAGE FORMAT

Each program message sent is also a query. You can only send one program message to

the RPM4 at time. After sending any program message, you must wait for the RPM4 to reply

before sending another program message. This reply will contain data, or a numeric error

message if the program message was invalid. You must wait for this reply before issuing

another program message to the RPM4. This insures that the RPM4 has completed the

program message. Most remote program messages will return a reply within 500 ms except:

“PR?”, “PRR?”, “SR?”, “ATM?”, “RATE?”: Up to 2 seconds.

“RPT”, “ARANGE”, “AUTOZERO=RUN”: Up to 3 seconds

The syntax and format used for each program message in the classic mode is listed next to

the keyword “Classic”’ in each program message summary in Section 4.4.4.

4.3.2

ENHANCED PROGRAM MESSAGE FORMAT

The enhanced program message format uses the IEEE Std. 488.2 format, syntax and status

reporting. Errors are reported using the IEEE Std. 488.2 status reporting model. If an error is

reported, the error is put into an Error Queue and the “ERR?” query program message can

be used to get a text description of the most recent error. If you are using the IEEE-488 port,

the service request line can be setup to be asserted if this occurs (see Section 4.5.2). In the

enhanced format, there are two possible program message types for every program

message. Each of these two types starts with the same basic text referred to as the program

message header. The two types are COMMAND type and QUERY type commands.

4.3.2.1

USING COMMAND TYPE COMMANDS

Enhanced format commands DO NOT reply when using the IEEE-488

interface unless a “?” is included in the command. Do not expect a response

from the RPM4’s IEEE-488 interface to non-query (no “?”) commands as

there is none. Remote software will time-out waiting for a response from

RPM4. However, in RS232 communications, there is always a response and

the response MUST be read prior to issuing another command.

The COMMAND type of program message executes a process and can

additionally send data to the RPM4 in the form of comma delimited arguments.

This data is usually a setting of some sort that is stored in the RPM4. If data is

specified, it must be preceded by at least one white space from the program

message header and be within the range and format described in the program

message description. The keyword “Command:” appears to the left of the

required syntax in each program message description in Section 4.4.4.

If you are using the IEEE-488 port, the Command type does not generate a reply

unless you place a query operator “?” immediately after the command. You also

may send multiple program messages at once by separating each program

message with a semicolon. The commands are queued and executed in as

received order after the entire message stream has been received, so care in

determining order of execution is needed.

If you are using the RS232 port COM1, the Command type will always generate

a reply so you must wait for a reply before issuing another program message.

Because of this, you can only send one Command program message at a time

while using the COM1 port.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

Examples:

•

IEEE-488 enhanced mode command series using query operator:

“*CLS?” (Clear the error queue. Wait for reply)

“UNIT? KPA” (Generates a reply. User must wait for reply before continuing)

“MMODE? A” (Generates a reply. User must wait for reply before continuing)

“PR?”

IEEE-488 enhanced mode commands without query operator:

“*CLS” (Clear the error queue. No reply)

(Generates a reply. User must wait for reply before continuing)

•

“UNIT KPA” (No reply)

“MMODE A” (No reply)

“ERR?”

(Wait for reply. User should use “ERR?” query following a

series of non query commands to check for errors that may

have occurred)

•

IEEE-488 enhanced mode multiple commands without query operator:

“*CLS”

(Clear the error queue. No reply)

(Two command at once. No reply)

“UNIT KPA;MMODE A”

“ERR?”

(Wait for reply. User should use “ERR?”

query following a series of non query

commands to check for errors that may

have occurred)

COM1 enhanced mode command:

“*CLS” or “*CLS?”

(Clear the error queue. Wait for reply)

“UNIT KPA” or “UNIT? KPA” (Generates a reply. User must wait for

reply before continuing)

“MMODE A” or “MMODE? A” (Generates a reply. User must wait for

reply before continuing)

“PR” or “PR?”

(Generates a reply. User must wait for

reply before continuing)

4.3.2.2

USING QUERY TYPE COMMANDS

The QUERY type of program message just requests data from the RPM4.

Placing the query operator “?” immediately after the command creates a query.

You must wait for a reply with a query. If you send any type of program

message to the RPM4 after a query before receiving a reply, the program

message is discarded and an error is generated. Errors are reported using the

IEEE Std. 488.2 status reporting model. A Query program message always ends

with a question mark. Most queries return a reply within 200 ms except:

“PR?”, “PRR?”, “SR?”, “ATM?”, “RATE?”: Up to 2 seconds.

“RPT”, “ARANGE”, “AUTOZERO RUN”: Up to 3 seconds

The syntax for using a QUERY program message is listed next to the keyword

“Query:” in each program message summary in Section 4.4.4. Please note that

queries in enhanced mode via the IEEE-488 port that results in an error will not

result in a reply. You must check the error queue (use the “ERR” querie) to see

if an error has occurred.

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4. REMOTE OPERATION

4.4

COMMANDS

4.4.1

PROGRAMMING MESSAGES

Some commands accept an optional suffix. This suffix can be used to specify the explicit Q-RPT

to address. In most cases, each Q-RPT in the RPM4 operates as an independent

measurement device. If the suffix is not specified, then the “Active” Q-RPT is assumed.

The “RANGE” or “ARANGE” command can be used to select the “Active” Q-RPT. There are

some limitations to use of the suffix when the RPM4 is in differential mode (see Section

3.3.3.1) or the “HL” Q-RPT is active (see Section 3.2.4). See the program message

descriptions for suffix use with a specific command.

Table 16. Program Message List

COMMAND

DESCRIPTION

‘n’ indicates an

optional suffix

Send a command string out of the RPM4 COM2 port.

Stop pending operations

Read or set a new AutoRange to use.

Read the current atmospheric pressure (on-board barometer).

Read or set the status of the AutoZ automatic zeroing function.

Run AutoZero.

Read or set the on-board barometer calibration

Read or set the configuration of the COM1 port.

Read or set the configuration of the COM2 port.

Enable continuous measurements

ABORT

ARANGEn

ATM

AUTOZEROn

AUTOZEROn=RUN

CALAMB

COM1

COM2

CONTn

DATE

Read or set the current date.

Read the last error message.

ERR

Read or set the GPIB interface address.

GPIB

Read or set the fluid head settings.

HEAD

Read or set the RPM4 alphanumeric asset ID tag.

Selects “classic” program message format

Selects “enhanced” program message format

Read or set the lower limit for the current range (negative gauge and differential

modes only).

LLn

Return control to the RPM4 front panel.

Read the power-up memory test status.

LOCAL

MEM

Read or change the active measurement mode.

Read or set the type of program message format to use.

Read or set the status of low vent valve (Gxxx or BGxxx Q-RPT only)

Read or set the user Lo Q-RPT calibration information.

Read or set the user Lo Q-RPT calibration information (old command).

Read the next RPM4 pressure.

MMODEn

MSGFMT

NVENTn

PCALn

PCAL:XX

PRn

Read the next RPM4 pressure, rate, and ATM.

Read the last RPM4 pressure, rate and ATM.

Select a Q-RPT to be “active” in it’s default full scale range

Read the next available rate of change of pressure.

Read or set the Q-RPT measurement read rate and mode

Read or set a flag that is cleared by a Not Ready condition.

Enable remote local lockout operation.

Read or set the pressure display resolution for the current Q-RPT and range.

Reset the RPM4 to default user parameters.

Read the available Q-RPT data.

PRRn

QPRRn

RANGE

RATEn

READRATEn

READYCKn

REMOTE

RESn

RESET

RPTn

Read or set the front panel screen saver period.

Read or set the SDS state for a specific Q-RPT

Read or set the active Q-RPT SDS state

Read or set the SDS mode for a specific Q-RPT

Read the serial number of the RPM4.

SCRSAV

SDSn

SDSACT

SDSAUTOn

Read the next available pressure status (Ready/Not Ready).

Read or set the stability required for a Ready condition.

Read or set the stability required for a Ready condition (% span/ s).

Read or set the current time of day.

SRn

SSn

SS%n

TIME

Convert a pressure in Pascal to pressure in the current units.

Read or set the user defined pressure unit.

UCOEFn

UDU

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RPM4™ OPERATION AND MAINTENANCE MANUAL

COMMAND

DESCRIPTION

‘n’ indicates an

optional suffix

Read or set the upper limit for the current range.

ULn

Read or set the pressure unit of measure for the current range.

Read the RPM4 software version.

UNITn

VER

Read or set the AutoZero Z_offsetfor the specified Q-RPT.

Read or set the AutoZ Z_offsetfor the specified Q-RPT (old command).

ZOFFSETn

ZOFFSET:XX

4.4.2

ERROR MESSAGESS

Table 17. Error #s and Descriptions

DESCRIPTION

ERR# 0

ERR# 2

“OK”

“Text argument is too long”

“Arguments cannot be 0”

“External device not detected”

Not used

ERR# 3

ERR# 4

ERR# 5

ERR# 6

“Numeric argument missing or out of range”

“Missing or improper command argument(s)”

“External device time-out error”

“Unknown command”

ERR# 7

ERR# 8

ERR# 9

ERR# 10

ERR# 11

ERR# 12

ERR# 13

ERR# 14

ERR# 17

ERR# 18

ERR# 19

ERR# 20

ERR# 21

ERR# 22

ERR# 23

ERR# 25

ERR# 26

ERR# 27

ERR# 28

ERR# 29

ERR# 30

ERR# 31

ERR# 32

ERR# 37

ERR# 38

ERR# 39

ERR# 45

ERR #46

ERR #52

ERR# 53

“Missing or invalid command suffix”

“Command missing argument”

“System overpressured” or “overpressure may result”

“Text queue overflow”

“User unit not defined”

Not used

“Command not yet available”

“Not available with absolute units”

“Not available with gauge device”

Not used

“Pressure is not stable”

“Option not available or installed”

Not used

“COM port failed to initialize”

“Internal device failure”

“Device failure”

“Device not available”

“Must be on range HI”

“Exceeds upper or lower limit”

“Not stable enough”

“Data table is full”

“Selected range is not available”

“Data verify error”

“Argument not allowed”

“Argument cannot be negative”

“Command obsolete”

“Not Available”

Page 86

4. REMOTE OPERATION

4.4.3

PROGRAM MESSAGE DESCRIPTION OVERVIEW

Each program message description is separated into the following sections:

Purpose

A brief description of the programs message’s function.

Command

This is the Enhanced program message syntax to send data to the RPM4 or to execute an

RPM4 function. The RPM4 must be set to use the enhanced format (see Section 3.5.2.3)

to use the syntax and style shown. It may be sent alone, or followed by at least one white

space and additional argument(s) to show that arguments can be passed. If there are

multiple arguments, then commas must separate them. If you are using the IEEE-488 port,

multiple command type program messages can be sent in one message if you separate

them with a semicolon. There will be no reply from the RPM4 using the IEEE-488 port

unless the command is immediately followed by the query operator “?”. If you are using

the COM1 port, the PPC1 will reply and you must wait for this reply. If this field is not

listed in the program message description, then the Command type is not supported when

using the Enhanced format.

Query

This is the Enhanced program message syntax to request data from the RPM4. The RPM4

must be set to use the enhanced format (see Section 3.5.2.3). The RPM4 will always

reply to a query. You must wait for this reply before issuing another program message. If

this field (Query) is not listed in the program message description, then the Query type for

the program message is not supported when using the Enhanced format.

This is the Classic program message syntax to send data to the RPM4, to execute an

RPM4 function, or to query for data. The RPM4 must be set to use the classic format

(see Section 3.5.2.3). The command may be followed by a ‘(=)’ and additional argument

characters to show that argument(s) can be passed. If there are multiple arguments, then

commas must separate them. The RPM4 will always reply to a Classic program message.

You must wait for this reply before issuing another program message. If this field is not listed

in the program message description, then it is not supported when using the classic

format.

Classic

Suffix

Some commands support an optional suffix. This suffix is used to specify a Q-RPT to which

the command applies, since many settings are Q-RPT specific:

Suffix of ‘1’ for Hi Q-RPT access

Suffix of ‘2’ for Lo Q-RPT access

Suffix of ‘3’ for HL Q-RPT access.

If an optional suffix is allowed but not given, then the “Active Q-RPT” will be addressed. The

“Active Q-RPT” is the Q-RPT that is currently displayed on the top line of the front panel of the

RPM4, and is identified by the text label in the upper right of the pressure display screen. The

last Q-RPT ranged or selected using the “RANGE” or “ARANGE” commands is the “Active” Q-

RPT. The “ARANGE”, “RANGE” or “RPT” command query can be used to determine which

Q-RPT is currently active. With the Hi Q-RPT In differential mode of operation, there are some

limitations on access to the Lo Q-RPT, and with the HL Q-RPT there are limitations on access

to both the Hi and the Lo Q-RPTs independently.

Arguments

Default

If the program message can be used to set data inside the RPM4, then this section describes

the arguments and their limits.

If the program message can be used to set data inside the RPM4, then this line shows

(using the enhanced format) the default setting from the factory.

Remarks

Example

This field has the details and remarks about the command.

Examples are given for the enhanced and classic methods.

Enhanced:

An example of the use of an enhanced format program message to be

sent to the RPM4 is shown. The message sent to the RPM4 appears after

the “Cmd sent:” label. If only a Query type exists, the “Query sent:”

label is shown instead. Directly under this label, “Query reply” shows a

typical reply to a query type. “Reply:” shows that a query format does

not exist. It may have a short description next to it.

Classic:

An example of the use of a classic program message to be sent to the

RPM4 is shown. The command sent to the RPM4 appears after the

“Cmd sent:” label. The “Reply” label shows a typical reply to the

“Sent” example. It may have a short description next to it.

Errors

If the program message can report an argument error, the types of errors are listed.

If using the classic format or the COM1 port, the error message is replied after receiving

the program message. If using the enhanced format via the IEEE-488 port, the error

condition is handled by the status reporting model which stores the errors in an Error

Queue and can be programmed to assert the IEEE-488 SRQ line to signal an error has

occurred. In either case, the “ERR” or “ERR?” program message can be used to

retrieve a text description of the error.

See Also

Indicates related commands (“----“) and refers to manual sections giving detail on RPM4

operation corresponding to the program message.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

4.4.4

PROGRAM MESSAGE DESCRIPTIONS

Purpose

Classic

Arguments

To allow the host PC to communicate with a device connected to the RPM4 COM2 port.

“#xx”

xx:

The string to send out of the RPM4 COM2 port. It must be less than

40 characters long.

Remarks

The RPM4 COM2 port can be used to communicate to another RS232 device (such as

another RPM4). This allows the user to use a single COM port or IEEE-488 port on the

host computer to communicate with the RPM4 and another RS232 device. A carriage

return and a line feed (<CR><LF>) are added to the string.

After this program message is issued, the RPM4 will reply back every string received by

the RPM4 COM2 port that is terminated with a carriage return. Line feeds are discarded.

This will discontinue when the next query is sent to the RPM4.

There is no other reply from this program message. Prior to using this program message,

you must ensure that the RPM4 COM2 port is correctly set up to communicate with the

device on COM2. Refer to the “COM2=“ program message.

Example

(classic)

Sent:

Reply:

“#VER”

“DH INSTRUMENTS, INC RPM4 us A1000/A0015 Ver2.00 ”

This example assumes that a second RPM4’s COM1 port is connected to the RPM4

COM2 port. This example gets the version of the second RPM4.

See Also

“COM2”

3.5.2

ABORT

Purpose

Cancels any pending data requests by the “PR”, “PRR” “RATE”, “SR” or “CONT”

commands.

Command

Classic

“ABORT”

Remarks

Example

(enhanced)

Example

(classic)

See Also

This program message is usually used to ensure the RPM4 is in an idle condition.

Cmd sent:

Reply:

“ABORT”

“ABORT” (no reply if IEEE-488)

Sent:

“ABORT”

Reply:

“ABORT”

“PR”, “PRR” “RATE”, “SR” or “CONT”

3.2.1

Page 88

4. REMOTE OPERATION

ARANGEn

Purpose

Command

Read or set a new AutoRange range to use.

“ARANGEn Range, unit, mode (,RptLabel)” (set to user defined range)

“ARANGE Q-RPTLabel”

(set to Q-RPT default range)

Query

“ARANGEn?”

Classic

“ARANGEn= Range, units, mode (,RptLabel)” (set to user defined range)

“ARANGE= Q-RPTLabel”

(set to Q-RPT default range)

Query

“ARANGEn”

Optional Suffix

“n”

A suffix may be used instead of “RptLabel”

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT

Arguments

Range:

Unit:

Mode:

The AutoRange maximum pressure. Cannot be negative.

The unit of measure of the Range argument.

The measurement mode of the Range argument:

“A” for absolute

“G” for gauge

“N” for negative gauge

Measured pressure values are returned with “g” to identify measurement

mode for both gauge and negative gauge measurement modes.

RptLabel:

(optional)

One of the Q-RPTs that is available.

“IH”: Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF. HL Q-RPT if

the Hi and Lo Q-RPTs are OFF.

“IL”: Lo Q-RPT

“HL”: HL Q-RPT.

Remarks

The ARANGE command is used to define an RPM4 range by specifying a desired unit of

measure, measurement mode and maximum pressure, and have the RPM4 pick the best

available Q-RPT and make adjustments to optimize operation in that range.

The optional suffix or the “RptLabel” argument can be used to specify which Q-RPT you

wish to use for the AutoRange range instead of allowing the RPM4 to pick the best Q-

RPT. By using this option you can override the internal logic that picks the most suitable Q-

Q-RPT. This Q-RPT specified must be valid for the maximum pressure and measurement

mode specified.

The reply indicates the current range data, including the Q-RPTLabel used for the range.

If “inWa” is specified for the unit, the temperature reference can be given after the unit

text (“inWa4”, “inWa20” or “inWa60” corresponding to inWa at 4 °C, 20 °C or 60 °F). If no

number is given, a default of 20 °C is assumed. There is no indication of the temperature

reference in the reply.

If you just specify the Q-RPTLabel without any other arguments, the Q-RPT specified will

become active in it’s last range and settings. The previously set unit and measurement

mode for the Q-RPT specified will become active.

Example

(enhanced)

Example

(classic)

Example

(enhanced)

Example

(classic)

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Cmd sent:

“ARANGE?”

“100.00, psi, A, IH”

“ARANGE”

“100.00, psi, A, IH”

(read the current range in the current units)

“ARANGE? 250, inWa4, G (range of 250 inWa @ 4 °C in gauge mode)

“250.00 inWa, G, IH”

“ARANGE=500, kPa, G

“500.00 kPa, G, IL”

(Lo Q-RPT is used)

(range of 500 kPa in gauge mode)

(Lo Q-RPT is used)

(range of 50 psi in absolute mode on

the Lo Q-RPT)

Example

(enhanced)

“ARANGE2 50, psi, A

Query reply:

Cmd sent:

“50.000 psi, A, IL”

“ARANGE IH

“500.000 kPa, A, IH”

(No reply if GPIB-488)

(Hi Q-RPT’s prev range made active)

(No reply if GPIB-488)

Example

(enhanced)

Query reply:

ERR# 6:

ERR#10:

Errors

“Range“ maximum pressure exceeds available Q-RPTs or is negative.

RPT specified by the optional suffix is not valid for the current operating

conditions

ERR# 19:

ERR# 20:

ERR# 29:

ERR# 53:

Cannot Range to ‘0’ with absolute units.

Cannot Range to ‘0’ with gauge units.

Correct type of Q-RPT for the selected “Mode” is not available.

RPT specified is not available.

See Also

“RPT”, “RANGE”, “MMODE”, “UNIT”

3.3.4, .3.2.4, 3.3.3, 3.3.2

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RPM4™ OPERATION AND MAINTENANCE MANUAL

ATM

Purpose

Reads the next measured pressure from RPM4’s on-board barometer (if present).

Query

“ATM?”

Classic

Remarks

“ATM”

The atmospheric pressure as measured by the RPM4 on-board barometer is returned in

the current pressure units of the active Q-RPT (always absolute). This measurement is

followed by the units text. Not all RPM4s are equipped with an on-board barometer.

Example

(enhanced)

Example

(classic)

Errors

Query sent:

Query reply:

Sent:

Reply:

ERR# 23:

3.5.7.1

“ATM?”

“97.12348 kPa a”

“ATM”

“97.12384 kPa a”

RPM4 is not equipped with a barometer.

See Also

AUTOZEROn

Purpose

Command

Query

Read or set the status of the AutoZ function.

“AUTOZEROn state”

“AUTOZEROn?”

Classic

“AUTOZEROn= state”

“AUTOZEROn”

Default

“AUTOZERO1”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Arguments

Remarks

‘state’:

’0’ Autozero OFF

’1’ Autozero ON

The RPM4 AutoZ function can be turned ON and OFF. There is a separate AutoZ flag for

the gauge, absolute, and differential measurement modes for each Q-RPT. This

command sets the AutoZ status for the current mode of the specified or the active Q-RPT

only. To set the sate of AutoZ for a measurement mode, you must be in that mode.

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Sent:

Query reply:

ERR# 7:

“AUTOZERO 0”

“0”

“AUTOZERO=0”

The argument was other than ‘0’ or ‘1’.

The suffix is invalid.

(No reply if GPIB-488)

ERR# 10:

See Also

“ZOFFSET”, “MMODE”

3.5.1

AUTOZEROn=RUN

Purpose

Command

Query

Run the AutoZero routine.

“AUTOZEROn RUN (,Pref)”

“AUTOZEROn? RUN (,Pref)”

“AUTOZEROn= RUN (,Pref)”

Classic

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

The AutoZ reference pressure in Pa. Optional when the RPM4 is not in

absolute measurement mode, as the reference is usually “0”.

Arguments

Remarks

‘Pref’:

The RPM4 AutoZ function can be remotely run with this command only if AutoZero is

ON. You should ensure that the pressure is stable for valid determination of Z_offset. If in

differential mode, the previous 5 measurements of the Q-RPTs are averaged for Z_offset

calculation so you should ensure that the RPM4 has been stable for at least 5

measurement cycles before running a remote AutoZ in differential mode.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“AUTOZERO RUN”

“OK”

(No reply if GPIB-488)

“AUTOZERO? RUN, 97283”

“OK”

“AUTOZERO=RUN”

“OK”

An argument was not given for the AutoZ reference in absolute mode.

(abs AutoZero to 97283 Paa)

Query reply:

ERR# 6:

ERR# 10:

ERR# 53

Invalid suffix

AutoZero is currently OFF.

See Also

“ZOFFSET”, “MMODE”, “AUTOZERO”

3.5.1

Page 90

4. REMOTE OPERATION

CALAMB

Purpose

Command

Query

Read or set the on-board barometer calibration.

“CALAMB adder, mult, CalDate”

“CALAMB?”

Classic

“CALAMB=adder, mult, CalDate”

“CALAMB”

Defaults

“CALAMB = 0.0, 1.0, 19800101”

Arguments

Adder:

Mult:

CalDate:

The Barometer calibration adder (PA), in Pascal.

The Barometer calibration multiplier (PM) from 0.1 to 100.

The date of the calibration in the format “YYYYMMDD”

Remarks

The barometer calibration information can be accessed with this program message. Using this

program message overwrites the current calibration coefficients, so caution must be used.

Changes made take effect immediately.

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Sent:

Reply:

ERR# 6:

3.5.7.1, 5.3

“CALAMB? 2.1, 1.000021, 20011201”

2.10, 1.000021, 20011201”

“CALAMB=2.1, 1.000021, 20011201”

2.10, 1.000021, 20011201”

One of the arguments is out of range.

“

See Also

COM1

Purpose

Command

Query

Read or set the RS232 settings for the COM1 port.

“COM1 baud, parity, data, stop”

“COM1?”

Classic

“COM1=baud, parity, data, stop”

“COM1”

Arguments

Baud:

Parity:

Data:

Stop:

The baud rate. This may be ‘300’, ‘600’,’1200’,’2400’,’4800’, ‘9600’ or ‘19200’.

The data parity. This may be ‘O’ for odd, ‘E’ for even, or ‘N’ for none.

The number of data bits. This may be ‘7’ or ‘8’.

The number of stop bits. This may be ‘1’ or ‘2’.

Defaults

Remarks

“COM1 2400,E,7,1”

The COM1 port is used to communicate to the RPM4. When the COM1 port configuration of the

RPM4 is changed, the program message reply (COM1 use only) is sent at the old COM1 settings,

but all subsequent communications are accomplished at the new COM1 settings.

A 250ms or longer delay after receiving the reply to this command will ensure that the RPM4 has

changed the COM port settings and is ready for communications at the new settings.

Example

(enhanced)

Cmd sent:

Query reply:

“COM1 9600,N,8,1”

“9600,N,8,1” (No reply if GPIB-488)

Example

(enhanced)

Cmd sent:

Query reply:

“COM1? 9600,N,8,1”

“9600,N,8,1”

Example

(classic))

Sent:

Reply:

“COM1=9600,N,8,1”

“9600,N,8,1”

Errors

See Also

ERR# 7:

“COM2”

3.5.2.1

Missing or improper program message argument(s).

COM2

Purpose

Command

Query

Read or set the RS232 settings for the COM2 port.

“COM2 baud,parity,data,stop”

“COM2?”

Classic

“COM2= baud,parity,data,stop”

“COM2”

Arguments

baud:

parity:

Data:

stop:

The baud rate. This may be ‘300’, ‘600’,’1200’,’2400’,’4800’, ‘9600’ or ‘19200’.

The data parity. This may be ‘O’ for odd, ‘E’ for even, or ‘N’ for none.

The number of data bits. This may be ‘7’ or ‘8’.

The number of stop bits. This may be ‘1’ or ‘2’.

Defaults

Remarks

“COM2 2400,E,7,1”

COM2 is generally used to allow the host computer to communicate through the RPM4 to an

additional device connected to COM2. This can be useful if the host computer does not have 2

serial ports available.

Example

(enhanced)

Cmd sent:

Query reply:

“COM2 9600,N,8,1”

“9600,N,8,1”

(No reply if GPIB-488)

Example

Cmd sent:

“COM2? 9600,N,8,1”

(enhanced)

Query reply:

“9600,N,8,1”

Example

(classic)

Sent:

Reply:

“COM2=9600,N,8,1”

“9600,N,8,1”

Errors

ERR# 7:

Missing or improper program message argument(s).

See Also

“COM1”

3.5.2.1

Page 91

RPM4™ OPERATION AND MAINTENANCE MANUAL

CONTn

Purpose

Query

Have the RPM4 reply continuously as each new measurement becomes available.

“CONTn?”

Classic

“CONTn”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

This command is somewhat different than most as it enables the RPM4 to continuously output the

selected Q-RPT’s measurement without further queries. This continues until the next query is

received by the RPM4, or if the ABORT” or “*CLS” command is received. The frequency of the

measurements is determined by the readrate of the Q-RPT. The data returned includes the

pressure of the specified or active Q-RPT, current unit of measure and measurement mode.

Example

(enhanced)

Example

(classic)

Query sent:

Query reply:

Query sent:

Reply:

“CONT1?”

“1936.72 kPa a” (repeats every measurement cycle)

“CONT”

“1936.72 kPa a” (repeats every measurement cycle)

See Also

“PR”, “READRATE”

DATE

Purpose

Command

Query

Read or set the RPM4 date.

“DATE date”

“DATE?”

Classic

“DATE= date”

“DATE”

Arguments

Remarks

date:

The date in the numerical only format “YYYYMMDD”

The RPM4 has an internal real time calendar clock. The span of acceptable dates ranges

from 19800101 to 20791231. The reply is always in the YYYYMMDD format.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

Reply:

ERR# 6:

“TIME”

“DATE 20030115”

“20030105”

“DATE? 20030105”

“20030105”

“DATE=20021201”

“20021201”

Missing or improper program message argument(s).

(No reply if GPIB-488)

See Also

3.5.5.3

ERR

Purpose

Query

Read the new available error message from the Error Queue.

“ERR?”

Classic

Remarks

“ERR”

This program message obtains additional details about an error that has occurred. If the user

receives an “ERR# nn” reply, or the enhanced mode is enabled using the IEEE-488 interface and

an error has been detected, the error is put into a FIFO Error Queue. The “ERR” program

message pulls and replies the oldest error message available. In “classic” mode only the most recent

error can reside in the queue. “OK” is replied if there are no error messages left. If an error occurs in

enhanced mode using the IEEE-488 interface, no reply is generated even if the command was a

query.

Example

(enhanced):

Example

(classic)

Query sent:

Query reply:

Sent:

“ERR?”

“Numeric argument missing or out of range”

“ERR”

“Numeric argument missing or out of range”

Reply:

See Also

4.4.2

Page 92

4. REMOTE OPERATION

GPIB

Purpose

Command

Query

Read or set the GPIB interface address.

“GPIB addr”

“GPIB?”

Classic

“GPIB=addr”

“GPIB”

Defaults

“GPIB 10”

Arguments

Remarks

Addr:

The address of the IEEE-488 (GPIB) interface (1 to 30)

The GPIB address is changed following the reply of this command. Each device on a GPIB

interface bus requires a unique address.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Cmd sent:

Query reply

Cmd sent:

Query reply

Sent:

“GPIB 21”

“21”

“GPIB? 21”

“21”

“GPIB=21”

“21”

(No reply if GPIB-488)

Reply:

Errors

See Also

3.5.5.4

Page 93

RPM4™ OPERATION AND MAINTENANCE MANUAL

L2 / L3

Purpose

Read or set the type of program command format to use (classic or enhanced).

Command

“L2”enables “classic” mode

“L3”enables “enhanced” mode

Defaults

Remarks

“L2”

(Classic mode)

The user can select the type of remote command format using these simplified commands.

There is no query format. This format must agree with the format sent to the RPM4. This

command is a replacement for the “MSGFMT” command.

Example

(enhanced)

Example

(classic)

Cmd sent:

Query reply:

Sent:

“L3”

“L2”

(No reply if IEEE-488)

Reply:

See Also

“MSGFMT”

4.3, 3.5.2.3

LLn

Purpose

Read or set the lower pressure limit for the active range and measurement mode (negative

gauge or differential measurement mode only).

Command

Classic

“LLn limit”

“LLn =limit”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL

Q-RPT is not active.

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement

mode is not differential.

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.

Arguments

Remarks

"limit”:

The lower pressure limit for the current pressure range in the specified Q-

RPT’s current unit of measure unit and measurement mode. Value is always

a negative value of gauge pressure.

Negative gauge and differential modes in RPM4 have a lower limit. If the pressure is less

than the lower limit, the pressure display flashes. This feature should always be used to

prevent accidental over (under) pressure of a device under test.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Reply:

Cmd sent:

Reply:

Sent:

Reply:

ERR# 6:

ERR# 10

ERR# 23

“UL”, “MMODE”

3.4.4, 3.3.3

“LL -4”

“-4 kPa g”

“LL? -4”

“-4 kPa g”

“LL=-4”

“-4 kPa g”

The limit argument is invalid.

(no reply if IEEE-488)

The suffix is invalid

The mode must be negative gauge to specify a lower limit.

See Also

LOCAL

Purpose

Command

Classic

Returns control to the RPM4 front panel.

“LOCAL”

Remark

The REMOTE program message can lock the front panel out completely. The user can return

to local operation by sending the LOCAL program message, sending the IEEE-488 ‘GTL’

command (if in enhanced format), or by cycling RPM4 power.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Cmd sent:

Reply:

Cmd sent:

Reply:

Sent:

Reply:

“LOCAL”

“LOCAL?”

“LOCAL”

(no reply if IEEE-488)

See Also

“REMOTE”

Page 94

4. REMOTE OPERATION

MEM

Purpose

Query

Classic

Remarks

Read the status from the power-up memory test.

“MEM?”

“MEM”

The RPM4 system memory stores the user settings (units, resolution) and retains them when

the unit is OFF. On power-up, this memory is checked. If this memory is corrupted, all user

settings are reset to default , and the MEM status is set to reflect this.

Example

(enhanced)

Query sent:

Reply:

“MEM?”

“0” RPM4 data corrupted and was set to factory defaults.

“1” The memory was found to be OK on power-up.

“MEM”

“MEM=0” RPM4 data corrupted and was set to factory defaults.

“MEM=1” The memory was found to be OK on power-up.

Example

(classic)

Sent:

Reply:

See Also

3.5.9, 3.5.7.5

MMODEn

Purpose

Command

Query

Read or change the active measurement mode.

“MMODEn mode”

“MMODEn?”

Classic

“MMODEn=mode”

“MMODEn ”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL

Q-RPT is not active.

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement

mode is not differential.

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.

Arguments

Mode:

"A"

"G"

"N"

“D”

Absolute mode

Gauge mode

Negative gauge mode

Differential mode (available only for the Hi Q-RPT)

Measured pressure values are returned with “g” to identify measurement

mode for both gauge and negative gauge measurement modes. Differential

mode restricts access to settings on the Lo Q-RPT.

Remarks

The measurement mode can also be set using the “UNIT” command but the “UNIT” command

does not distinguish between gauge and negative gauge in it’s reply, while the “MMODE”

does. Measurement mode is range specific.

Example

(enhanced)

Example

(enhanced)

Example

(enhanced)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Cmd sent:

Query reply:

ERR# 6:

“MMODE A”

“A”

“MMODE? A”

“A”

“MMODE=G”

“G”

Invalid argument text.

(No reply if IEEE-488)

ERR# 7:

ERR#10:

ERR# 20:

Abs mode only with altitude units or gauge mode only with gauge Q-RPT.

The suffix indicating the Q-RPT is invalid for the current conditions.

Absolute or negative gauge mode not available with gauge Q-RPT.

Absolute Q-RPT with an absolute and negative gauge OFF calibration.

The current range cannot support gauge mode.

ERR# 53:

Gauge mode range would be negative.

Lo Q-RPT not suitable for differential mode.

See Also

“UNIT”, “ARANGE”

3.3.3

Page 95

RPM4™ OPERATION AND MAINTENANCE MANUAL

MSGFMT

Purpose

Command

Query

Read or set the type of program command format to use (enhanced or classic).

“MSGFMT mode

“MSGFMT?”

Classic

“MSGFMT= mode

“MSGFMT”

Arguments

mode:

‘1’ to use the enhanced command format.

‘0’ to use the classic command format.

Defaults

Remarks

“MSGFMT 0”

The user can select the type of remote command format to use. This format must agree with the

format sent to the RPM4

The enhanced query form of this command (“MSGFMT? n”) should always be used to set the

desired format, as it will be accepted regardless of the current format (classic or enhanced).

It is recommended to use the “L2” and “L3” commands instead of this command for new designs.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“MSGFMT 1”

“1”

“MSGFMT? 1”

“1”

“MSGFMT=1”

Missing or improper program message argument(s).

(No reply if IEEE-488)

Reply:

ERR# 6:

See Also

“L2 / L3”

4.3, 3.5.2.3

NVENTn

Purpose

Command

Query

Read or set the status of low (negative) vent valve (Gxxx or BGxxx Q-RPT only)

“NVENTn mode”

“NVENTn?”

Classic

“NVENTn= mode”

“NVENTn”

Default

“NVENTn AUTO”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given. The “Hi” Q-RPT is assumed if the

HL Q-RPT is active and no suffix is given.

‘1’ Specify the Hi Q-RPT

‘2’ Specify the Lo Q-RPT

Arguments

Remarks

Mode:

’0’ to close the low vent valve.

’1’ to open the low vent valve.

‘AUTO’ for the RPM4 to automatically open and close the low vent valve.

Gxxx or BGxxx Q-RPTs each have a low vent valve that is used to vent the TEST(-) port.

This valve is normally controlled automatically depending on current RPM4 operation but it can

be commanded to open or close using the “NVENT” command.

The reply includes two fields. The first indicates the low vent status. The second indicates

whether the low vent function is AUTO or MANUAL

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“NVENT? 0”

“0, MANUAL”

“NVENT? AUTO”

“1, AUTO”

“NVENT=1”

“0, MANUAL”

Query reply:

See Also

3.5.7.4

Page 96

4. REMOTE OPERATION

PCALn

Purpose

Command

Query

Read or set the calibration information for the Hi or Lo Q-RPT.

“PCALn adder, mult, CalDate”

“PCALn?”

Classic

“PCALn= adder, mult, CalDate”

“PCALn”

Defaults

“PCALn = 0.0, 1.0, 19800101”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given. The Hi Q-RPT is assumed if the HL

Q-RPT is active and no suffix is given.

‘1’ Specify the Hi Q-RPT

‘2’ Specify the Lo Q-RPT

Arguments

Remarks

Adder:

Mult:

CalDate:

The Q-RPT calibration adder (PA). In Pascal.

The Q-RPT calibration multiplier (PM) from 0.1 to 100.

The date of the calibration in the format “YYYYMMDD” by default. Any other

format up to 8 characters long is also accepted, and the replied format is in th

previously entered format.

The user defined pressure calibration information for the specified Q-RPT (Hi or Lo) can be

accessed with this program message. The HL Q-RPT does not have it’s own calibration

information. Using this program message overwrites the current calibration coefficients, so caution

must be used. Changes made using this program message take effect immediately.

For compatibility with the obsolete style PPC3 “PCAL:HI” and “PCAL:LO” commands, “:HI” and

“:LO” can be used in place of the suffix “n” but this is not recommended for new applications.

Example

(enhanced)

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“PCAL2? 2.1, 1.000021, 20011201”

2.10 Pa, 1.000021, 20011201” (No reply if GPIB-488)

“PCAL? 2.1, 1.000021, 20011201”

2.10 Pa, 1.000021, 20011201”

“PCAL:HI? 2.1, 1.000021, 20011201” (PPC3 style is OK)

2.10 Pa, 1.000021, 20011201”

“PCAL1=2.1, 1.000021, 20011201”

“ 2.10 Pa, 1.000021, 20011201”

“

Reply:

Errors

ERR# 6:

ERR# 10:

5.2

One of the arguments is out of range.

The suffix is invalid.

See Also

PRn

Purpose

Query

Read the next available pressure measurement.

“PRn?”

Classic

“PRn”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

The next available pressure value for the specified or active Q-RPT is read in the current pressure

units. The data returned also contains Ready/Not Ready information, and the pressure unit of

measure and measurement mode.

The reply field is always 20 characters long. The first 3 characters of the reply are reserved for the

ready status. The ready status is described in the “SR” program message. The pressure value and

pressure unit of measure are right justified in this field.

After receiving this program message, the RPM4 replies back with the data after a new pressure

measurement cycle is complete. This can take up to the current read rate period (1.2 seconds by

default).

Example

(enhanced)

Example

(classic)

Query sent:

Query reply:

Query sent:

Reply:

“PR?”

“R

“PR”

“R

1936.72 kPa a”

See Also

“PRR”, “QPRR”, “SR”, “ABORT”, “READRATE”

3.1.1, 3.2.1, 3.5.7.2

Page 97

RPM4™ OPERATION AND MAINTENANCE MANUAL

PRR

Purpose

Read the next available Ready condition, pressure measurement, rate and on-board

barometer reading.

Query

“PRR?”

Classic

“PRR”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

The next available Ready condition, Q-RPT pressure measurement, rate of pressure change,

and barometric pressure is replied in the current pressure unit of measure. . This can take up

to the current read rate period (1.2 seconds by default). Each data field is separated by a

comma, and is returned in the following order:

ready, pressure UNITS, rate UNITS/s, atm UNITS

Here are the field descriptions:

ready:

pressure:

Three character ready status field. Refer to the “SR” command.

The measured pressure for the active Q-RPT in the current pressure unit.

This is followed by the current pressure unit.

rate:

atm:

The measured rate of pressure change for the active Q-RPT in the current

pressure unit per second. This is followed by the current pressure unit of measure.

The pressure measured by the RPM4 on-board barometer in the current

pressure unit (and always absolute). This is followed by the current pressure

unit. Not all RPM4s are equipped with an on-board barometer. This field is

missing if the RPM4 is not equipped with an on-board barometer.

“PRR?”

Example

(enhanced)

Query sent:

Query reply:

“R,2306.265 kPaa,0.011 kPa/s,97.000 kPa a”

“R,2306.265 kPaa,0.011 kPa/s”

(no barometer)

Example

(classic)

See Also

Query sent:

Reply:

“PR”, “QPRR”, “SR”

3.1.1, 3.2.1, 3.5.7.1

“PRR”

“R,2306.265 kPaa,0.011 kPa/s,97.000 kPa a”

QPRR

Purpose

Read the last Q-RPT pressure measurement, pressure rate and on-board barometer output

immediately.

“QPRR?”

“QPRR”

Query

Classic

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

The last measured Ready/Not Ready condition, active Q-RPT pressure measurement, rate of

pressure change, and barometric pressure is replied in the current pressure unit of measure

immediately. This program message is useful when a rapid response of measured pressure

is needed. It does not result in quicker pressure measurements. Each data field is separated

by a comma, and is returned in the following order:

Ready, pressure UNITS, rate UNITS/s, atm UNITS

Here are the field descriptions:

ready:

pressure:

Three character ready status field. Refer to the “SR” command.

The measured pressure for the selected Q-RPT in the current pressure unit.

This is followed by the current pressure unit and measurement mode.

The measured rate of pressure change for the active Q-RPT in the current

unit of pressure per second. This is followed by the current pressure unit.

The pressure measured by the RPM4 on-board barometer in the current

pressure unit (but always absolute). This is followed by the current pressure

unit. Not all RPM4s are equipped with an on-board barometer. This field is

missing if the RPM4 is not equipped with a barometer.

“QPRR?”

rate:

atm:

Example

(enhanced)

Query sent:

Query reply:

“R,2306.265 kPa a,0.011 kPa/s,97.000 kPa a”

“R,2306.265 kPa a,0.011 kPa/s” (no barometer)

Example

(classic)

See Also

Query sent:

Reply:

“PR”, “PRR”, “SR”

“QPRR”

“R,2306.265 kPa a,0.011 kPa/s,97.000 kPa a”

3.1.1, 3.2.1, 3.5.7.1

Page 98

4. REMOTE OPERATION

RANGE

Purpose

Change the active range to the default range of the Hi, Lo or HL Q-RPT. Replies the active

range full scale, pressure unit and measurement mode.

Command

Query

“RANGE Rng”

“RANGE?”

Classic

“RANGE= Rng”

“RANGE ”

Default

“RANGE IH”

Rng:

“IH” for the Hi Q-RPT

“IL” for the Lo Q-RPT

“HL” for the HL Q-RPT

Remarks

The active Q-RPT must be selected before making changes to settings that are dependent on the

range. Q-RPTs selected with this command are used with their full default pressure range. The reply

indicates the active range in psi if the RPM4 is a “US” version or in kPa if the RPM4 is an “SI” version.

Used as a simple query, the active range is returned, which can be an AutoRanged range or a

default range (see “ARANGE” cmd).

Example

(enhanced)

Example

(classic)

Example

(classic)

Errors

Cmd sent:

Query reply:

Sent:

Reply:

Sent:

Reply:

ERR# 6:

ERR# 29:

“RANGE? IL”

“2.2 psi g,IL”

“RANGE= IH”

“1000 psi a, IH”

“RANGE”

“220 psi a,IL”

Invalid Rng argument.

The selected Q-RPT is not available.

(select internal Lo Q-RPT in it’s full default range)

(select internal Hi Q-RPT in it’s full default range)

(request current range)

See Also

“ARANGE”, “RPT”

3.2.3, 3.3.1, 3.3.4

RATEn

Purpose

Query

Read the next available pressure rate of change.

“RATEn?”

Classic

“RATEn”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

The next available pressure rate of change in the current pressure unit per second is returned.

After receiving this program message, the RPM4 replies back with the data once a new pressure

measurement cycle is complete. This can take up to the current read rate period (1.2 seconds

by default).

Example

(enhanced)

Example

(classic)

Query sent:

Query reply:

Sent:

“RATE?”

“0.01 kPa/s”

“RATE2”

“0.03 kPa/s”

Reply:

See Also

“PRR”, “QPRR”.”READRATE”

3.3.6.2

Page 99

RPM4™ OPERATION AND MAINTENANCE MANUAL

READRATEn

Purpose

Command

Query

Read or set the specified or active Q-RPT read rate or auto read rate mode.

“READRATEn period”

“READRATEn?”

Classic

“READRATEn= period”

“READRATEn”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL

Q-RPT is not active.

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement

mode is not differential.

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.

Period to integrate the measurement over (ms). Can be from 200 ms to 20000

ms. Set to ‘0’ to enable automatic read rate.

Arguments

Remarks

“period ":

The RPM4 can have the speed in which it integrates each measurement (“read rate”) automatically

adjusted based on the rate, or it can manually set to a fixed period. Increasing the read rate increases

the reply time for pressure and rate queries. In differential mode and when using the HL Q-RPT, the Lo

Q-RPT read rate is always set to the same read rate as the Hi.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

Reply:

ERR# 6:

ERR#10:

“READRATE 1000”

“1000”

(No reply if GPIB-488)

“READRATE? 1000”

“1000”

“READRATE=1000”

“1000”

The “period” argument is out of range.

The suffix ‘n’ is invalid

See Also

“PR”, “PRR”, “SR”

3.5.7.2

READYCKn

Purpose

Command

Query

Read or set the Ready check flag.

“READYCKn 1”

“READYCKn?”

Classic

“READYCKn=1”

“READYCKn”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

The internal ready check flag is cleared whenever the specified or active Q-RPT reaches a

Not Ready (NR) condition. The “READYCK” query returns the status of the flag. The flag is

set by sending the “READYCK 1” program message while the Q-RPT is in a Ready condition.

The “READYCK” program message query can then be used at a later time to determine

whether a Not Ready condition has occurred since the ready check flag was set.

Example

(enhanced)

Example

(enhanced)

Example

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Cmd sent:

Query reply:

“READYCK1 1”

“1” (no reply if GPIB-488)

“READYCK1?”

“1”

“READYCK?”

(enhanced)

“1” (if Q-RPT condition has stayed Ready)

“0” (if Q-RPT condition has NOT stayed Ready)

“READYCK=1”

“READYCK”

“READYCK=1” (if Q-RPT condition has stayed Ready)

“READYCK=0” (if Q-RPT condition has NOT stayed Ready)

Argument is not a ‘0’ or a ‘1’.

Example

(classic)

Example

(classic)

Sent:

Query reply:

Sent:

Query reply:

Errors

See Also

ERR# 6:

“SR”

3.2.1

Page 100

4. REMOTE OPERATION

REMOTE

Purpose

Command

Classic

Lock out the front panel keypads during remote operation.

“REMOTE”

Remarks

The RPM4 goes into remote mode whenever communications take place. The user can

return to local operation by pressing the [ESC] key. The REMOTE program message locks

out the front panel completely. The only way to unlock the front panel after the “REMOTE”

command is using the “LOCAL” program message, the IEEE-488 “GTL” command, or by

cycling the RPM4 power.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Cmd sent:

Reply:

Cmd sent:

Reply:

Sent:

Reply:

“REMOTE”

“REMOTE” (no reply if IEEE-488)

“REMOTE?”

“REMOTE”

See Also

“LOCAL”

RESn

Purpose

Command

Query

To read or set the pressure display resolution for the active range.

“RESn res”

“RESn”

Classic

“RESn= res”

“RESn”

Default

“RESn=0.001”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Arguments

Remarks

res:

The pressure display resolution in % span of the specified Q-RPT range (0.0001 to 1 %

FS).

The pressure display resolution is defined as % span of the active range. The setting is

separate for each range, and changes as the range is changed.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“RES .01”

“0.01” (No reply if GPIB-488)

“RES? .01”

“0.01”

“RES=.01”

“0.01”

The argument is invalid.

Reply:

ERR# 6

See Also

3.4.2

RESET

Purpose

Command

Classic

Reset the user’s settings to factory defaults.

“RESET”

Remarks

The RPM4 has user settings (units, resolution, etc.) that can be reset to factory defaults. The

remote “RESET” program message corresponds to the front panel “Reset - Sets”. System

calibration coefficients and communications settings are not affected. The reset cycle takes up

to 3 seconds to complete. Remote communications should not take place during this period.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Cmd sent:

Reply:

Cmd sent:

Reply:

Sent:

Reply:

“RESET”

“RESET?”

“RESET”

(no reply if IEEE-488)

See Also

3.5.9.1

Page 101

RPM4™ OPERATION AND MAINTENANCE MANUAL

RPTn

Purpose

Query

Classic

Read the available Q-RPT identification data.

“RPTn”

“n”

Optional Suffix

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

Up to two (three including the HL Q-RPT which is a combination of the Hi and Lo) internal Q-

RPTs can be available for use in an RPM4. You can query the RPM4 for information about

each particular Q-RPT. The Q-RPT data is returned in the following format:

RPTLabel, Q-RPTLocator, Serial#, RngGa, RngAbs, Q-RPTMode

RngLabel:

RPT type label. This label identifies the Q-RPT type and range. This is

the same label used on the RPM4 front panel screen.

RptLocator:

Text field identifying the Q-RPT position in the RPM4 system.

“IH” identifies this as an internal, Hi Q-RPT

“IL” identifies this as an internal, Lo Q-RPT

Serial#:

RngGa:

RngAbs:

The serial number of the Q-RPT.

The Q-RPT default gauge mode range in the current pressure unit.

The Q-RPT default absolute mode range in the current pressure unit.

“NONE” appears in the field if the Q-RPT is a Gxxx, BGxxx or Axxx with

absolute and negative gauge modes OFF.

RptMode:

‘A’ if Q-RPT is Axxx and supports absolute, gauge and negative gauge

measurement modes.

‘G’ if Q-RPT is gauge Gxxx or Axxx with absolute and negative gauge

modes OFF and supports only gauge measurement mode.

‘N’ if Q-RPT is BGxxx and supports gauge and negative gauge

measurement modes.

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

ERR#4:

“RPT2?”

“A350K, IL, 82345, 35, 50,A”

“RPT3” (Get information on the HL Q-RPT)

“A7M, HL, 82345, 1000, 1000,A”

External device not detected.

Invalid suffix.

(Get information on the Lo Q-RPT)

ERR# 10:

See Also

3.2.3, 3.2.4

SDSn

Purpose

Read or set the OPEN/CLOSE status for the specified or active Q-RPT SDS systems. This

is equivalent to use of the SDS temporary OPEN/CLOSE function from the RPM4 front panel.

Command

Query

“SDSn close”

“SDSn”

Classic

“SDSn=close”

“SDSn”

Default

“SDSn=1”

Optional Suffi

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT’s SDS if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT’s SDS if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT’s SDS.

‘3’ Specify the HL Q-RPT’s SDS if the HL Q-RPT is active

Arguments

Remarks

”close”:

‘0’ to OPEN the SDS system.

‘1’ to CLOSE the SDS system.

Each Q-RPT of designation A7M or less can have an “SDS” system, which can be either

“OPEN” or “CLOSED”. This command allows access to each one without affecting the other,

regardless of whether the SDS for the selected Q-RPT is currently full time “ON” or “OFF”.

Caution must be used in differential mode or when using the HL Q-RPT, as this command

can allow you to have one Q-RPT open while the other Q-RPT is closed. If the “HL” Q-RPT

SDS is specified, then both the Hi and the Lo Q-RPT SDS will be affected. This command

does not affect the power up status of the SDS system.

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

ERR# 7:

“SDS2? 1”

“1”

“SDS1=0”

(close the Lo Q-RPT SDS)

(open the Hi Q-RPT SDS)

Argument not a ‘0’ or a ‘1’

ERR# 10:

ERR# 23:

ERR# 53:

Invalid suffix.

SDS not installed on this Q-RPT and pressure is close to ATM.

SDS not installed on this Q-RPT and pressure not close to ATM.

See Also

“SDSAUTO”, “SDSACT”

3.2.7, 3.3.8, 3.5.4

Page 102

4. REMOTE OPERATION

SDSACT

Purpose

Read or set the status for both the Hi and Lo Q-RPT’s SDS systems. This is equivalent to

use of the [SDS] key from the RPM4 front panel.

Command

Query

“SDS state”

“SDS”

Classic

“SDS=state”

“SDS”

Default

“SDS=1”

Arguments

”state”:

‘0’ OPEN the SDS system on the active Q-RPT and CLOSE the SDS

system on the “inactive” Q-RPT.

‘1’ to CLOSE the SDS system on both Q-RPTs.

Remarks

This command can be used to select one Q-RPT at a time, ensuring that the “inactive” Q-RPT

SDS is closed. If a Q-RPT’s SDS is full time “OFF”, then it is not be affected by this

command. The status of the active Q-RPT’s SDS system is replied. If the RPM4 is in

differential mode or the HL Q-RPT is active, then this command opens or close both the Hi

and Lo SDS at the same time, unless the SDS is full time “off”.

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

ERR# 7:

“SDS? 1”

“1”

“SDS=0”

Argument not a ‘0’ or a ‘1’

Invalid suffix or command argument.

SDS not installed on this Q-RPT

ERR# 10:

ERR# 23:

See Also

“SDSAUTO”, “SDS”

3.2.7, 3.3.8, 3.5.4

SDSAUTOn

Purpose

Read or set the automatic full time ON/OFF status for the specified or active Q-RPT SDS

systems. This is equivalent to use of the SDS full time ON/OFF function from the RPM4

front panel.

Command

Query

Classic

“SDSAUTOn on”

“SDSAUTOn”

“SDSAUTOn=on”

“SDSAUTOn”

“SDSAUTOn=1”

Default

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given. If the “HL” Q-RPT is the active Q-

RPT, and no suffix is specified, then the “Hi” Q-RPT is assumed

‘1’ Specify the Hi Q-RPT SDS

‘2’ Specify the Lo Q-RPT SDS

Arguments

Remarks

” on”:

‘0’ to turn the SDS system OFF.

‘1’ to turn the SDS system ON

Turning an SDS system to full time “OFF” or “ON” affects how the remote command

“SDSACT” and the front panel SDS button can affect each Q-RPT’s SDS system.

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

ERR# 7:

“SDSAUTO2? 1”

“1”

“SDSAUTO1=0”

Argument not a ‘0’ or a ‘1’

Invalid suffix.

ERR# 10:

ERR# 23:

SDS not installed on this Q-RPT

See Also

“SDSACT”, “SDS”

3.2.7, 3.3.8, 3.5.4,

SCRSAV

Purpose

Command

Query

Read or set the front panel display screen saver activation time.

“SCRSAV n”

“SCRSAV?”

“SCRSAV=n”

“SCRSAV”

Classic

Arguments

Default

The inactivity period (0 – 99 minutes) after which screen saver activates.

“SCRSAV 10”

Remarks

The RPM4 front panel will dim after a period of keyboard and remote inactivity. Setting this

value to ‘0’ disables this feature.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“SCRSAV 30”

“30”

“SCRSAV? 30”

“30”

“SCRSAV=30”

“30”

The argument was invalid.

(No reply if GPIB-488)

Reply:

ERR# 6

See Also

3.5.5.1

Page 103

RPM4™ OPERATION AND MAINTENANCE MANUAL

Purpose

Query

To read the serial number of the RPM4.

“SN?”

Classic

“SN”

Remarks

Example

(enhanced)

Example

(classic)

See Also

The RPM4 is serialized. The serial number can be read using this program message.

Query sent:

Query reply:

Sent:

“SN?”

“321”

“SN”

Reply:

“321”

3.5.5.4

Purpose

Query

Classic

Optional Suffix

Read the next available Ready/Not Ready status.

“SR?”

“SR”

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

The current Ready status can be read using this program message.

Possible replies:

“NR”

“R ”

The pressure is not ready within the limits defined by the stability criterion.

The pressure meets the ready criteria. The status is replied when the next pressure

measurement is finished.

“OL”

The pressure of one of the active Q-RPTs has exceeded the user defined upper or

lower limits.

“OP”

“ER”

The pressure of one of the Q-RPTs has exceeded the Q-RPT’s maximum limits.

An internal device failure has occurred.

Example

(enhanced)

Example

(classic)

Query sent:

Query reply:

Sent:

“SR?”

“NR”

“SR”

“NR”

Reply:

See Also

“PR”, “PRR”, “HS”, “SS”, “UL”, “LL” Commands

3.2.1, 3.4.4, 3.4.4.1

SS%n

Purpose

Command

Query

Read or set the current stability limit as a % of range.

“SS% limit”

“SS%?”

Classic

“SS%=limit”

“SS%”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Arguments

Remarks

Example

(enhanced)

Example

(enhanced)

Example

(classic)

limit:

The stability limit in %FS of the current active range.

The stability limit can be read and set as a percent of the full scale range of the Q-RPT range.

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“SS% .1”

“0.10 %”(No reply from GPIB-488)

“SS%? .1”

“0.10 %”

“SS%=.1”

“0.10 %”

Reply:

Errors

ERR# 6:

ERR# 10:

“SS”

The argument was invalid.

Invalid or missing command suffix.

See Also

3.4.3

Page 104

4. REMOTE OPERATION

SSn

Purpose

Command

Query

Read or set the current pressure stability limit.

“SS limit”

“SS?”

Classic

“SS=limit”

“SS”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Arguments

Remarks

Limit:

The stability limit in the current pressure unit of measure.

The stability limit can be read and set as a pressure. The stability limit is used as the

Ready/Not Ready criteria..

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“SS .1”

“0.10 kPa/s”

“SS? .1”

“0.10 kPa/s”

“SS=.1”

“0.10 kPa/s”

The argument was invalid.

Invalid or missing command suffix.

(No reply from GPIB-488)

Reply:

ERR# 6:

ERR# 10:

“SS%”

See Also

3.4.3

TIME

Purpose

Command

Query

Read or set the RPM4 internal clock.

“TIME hh:mmXX”

“TIME?”

Classic

“TIME=hh:mmXX”

“TIME”

Arguments

hh:mm:

XX:

The time in a 12 hour format using a colon delimiter

”am” or “pm”

“TIME 12:52PM”

“12:52pm”

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

(No reply if GPIB-488)

“TIME? 12:52PM”

“12:52pm”

“TIME=12:52PM”

“12:52pm”

Reply:

ERR# 7:

“DATE”

3.5.5.3

Missing or improper program message argument(s).

See Also

UCOEFn

Purpose

Query

To identify the coefficient used to convert 1 Pascal to the current pressure unit of measure.

“UCOEFn?”

Classic

“UCOEFn”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active

Remarks

The RPM4 handles all pressure values internally in Pascal. The coefficient replied is

equivalent of 1 Pa in the current pressure unit of measure. This program message allows the

user to convert pressures

Example

(enhanced)

Example

(classic)

Query sent:

Query reply:

Sent:

“UCOEF?”

“0.0010000000”

“UCOEF”

“0.0010000000”

Reply:

See Also

3.3.2, 3.5.6, 7.2.1

Page 105

RPM4™ OPERATION AND MAINTENANCE MANUAL

UDU

Purpose

Command

Query

Read or set the user defined pressure unit.

“UDU label, ucoef”

“UDU?”

Classic

“UDU=label, ucoef”

“UDU”

label:

User unit label (4 alphanumeric char maximum). It cannot be an already

supported unit label.

Ucoef:

“User unit conversion coefficient (units/Pa).

Default

“UDU USER,1.0”

Remarks

The user defined unit must be set up with the program message prior to remote or local

selection.

Example

(enhanced)

Example

(enhanced)

Example

(enhanced)

Errors

Cmd Sent:

Query reply:

Cmd Sent:

Query reply:

Sent:

“UDU MYUN, .001”

“MYUN, 0.001000”

“UDU? MYUN, .001”

“MYUN, 0.001000”

“UDU=MYUN, .001”

“MYUN, 0.001000”

(No reply if GPIB-488)

Reply:

See Also

3.5.6, 3.3.2

ULn

Purpose

Command

Query

Read or set an upper limit for the specified or active Q-RPT.

“Uln limit”

“Uln?”

Classic

“Uln=limit”

“ULn”

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL

Q-RPT is not active.

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement

mode is not differential.

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.

The upper limit pressure in the specified Q-RPT’s current pressure unit and

measurement mode. If the unit is meters, this value is be interpreted in kPa. If

the unit is feet, this value is be interpreted in psi.

Arguments

Remarks

“limit":

The RPM4 has an upper limit for each range and for each measurement mode (gauge, absolute, and

differential). If the pressure does exceed the upper limit, the pressure display flashes. This

feature should always be used to prevent accidental over pressure of a device under test.

Example

(enhanced)

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Cmd sent:

Query reply:

Sent:

Reply:

ERR# 6:

“LL”

“UL 1000”

“1000.00 kPa a” (No reply if GPIB-488)

“UL? 1000”

“1000.00 kPa a”

“UL=1000”

“1000.00 kPa a”

The “limit” argument is out of range.

See Also

3.4.4

Page 106

4. REMOTE OPERATION

UNITn

Purpose

Command

Read or set the pressure unit of measure unit and measurement mode.

“UNITn unit (, ref”)”

“UNITn unitn (, ref”)”

“UNITn unitg (, ref”)”

“UNITn unita (, ref”)”

“UNITn unitd (, ref”)”

“UNITn?”

Query

Classic

“UNITn=unit (, ref”)”

“UNITn=unitn (, ref”)”

“UNITn=unitg (, ref”)”

“UNITn=unita (, ref”)”

“UNITn=unitd (,ref”)”

“UNITn”

Optional Suffix

Arguments

Remarks

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL

Q-RPT is not active.

Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF

‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement

mode is not differential.

‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.

The text corresponding to the pressure unit of measure. A unit mode

character can optionally be added to the end of the units:

‘a’ for absolute measurement mode.

Unit:

ref:

‘g’ for gauge measurement mode.

‘n’ for negative gauge measurement mode.

‘d’ for differential measurement mode (Hi Q-RPT only)

The optional unit reference temperature only if the unit is “InWa”

This program message determines what unit of measure and what measurement mode is used to

display pressure values. Refer to Table 13 for a detailed list of the units available and their labels.

If the unit text is not followed by an explicit mode character (‘a’, ‘g’, ‘n’ or ‘d’) then “gauge” mode is

assumed. There can be a space between the unit text and the ‘a’, ‘g’, ‘n’ or ‘d’.

If the unit specified is “InWa”, an optional second argument “ref” can be set. The “ref” can be 4, 20,

or 60 corresponding to InWa at 4 °C, 20 °C or 60 °F. If this second argument is not given when

the unit is “InWa”, then the reference temperature is assumed to be 20 °C. This can also be added

directly onto the end of the Unit argument if desired.

The fifth character of the reply is always ‘a’ for absolute mode, ‘g’ for gauge/negative gauge mode

or ‘d’ for differential mode. White spaces precede this character if needed. The temperature

reference is added to the reply only if the unit is “InWa”.

The reply includes the measurement mode character in the fifth position, with an ‘a’ indicating

absolute mode, a ‘g’ indicating gauge or negative gauge mode or a ‘d’ indicating differential mode.

The “MODE” command can also be used to set the desired measurement mode only.

Example

(enhanced)

Cmd sent:

Query reply:

Sent:

Query reply:

Sent:

Query reply:

Cmd sent:

Query reply:

Sent:

“UNIT? kPaa”

“kPaa”

“UNIT? InWag, 4”

“inWag, 4”

“UNIT? InWaa60”

“inWaa, 60”

“UNIT psi n”

“psi g”

“UNIT=kPaa”

“kPaa”

Example

(enhanced)

Example

(classic)

(‘g’ used to indicate both gauge & neg gauge modes)

Reply:

Sent:

Reply:

“UNIT=InWag, 4”

“inWag, 4”

Errors

ERR# 7:

ERR# 6:

ERR# 20:

The unit is invalid.

The ref is invalid.

Absolute measurement mode and altitude units are not allowed with a gauge Q-RPT.

See Also

“MMODE”, “MODE”

3.3.2, 3.3.3, 3.5.6, 7.2.1

VER

Purpose

Query

Identify the RPM4, US or SI units, the Q-RPT labels and the software version.

“VER?”

Classic

Remarks

“VER”

The software version of the RPM4 can be read. This is useful for checking for the presence of the

RPM4 and for reference purposes. It indicates the internal Q-RPT(s) and software version.

Example

(enhanced)

Example

(classic)

Query sent:

Query reply:

Query sent:

Query reply:

“ID”, “*IDN?”

None

“VER?”

“DH INSTRUMENTS, INC RPM4 us A350K/BG15K Ver1.00 ”

“VER?”

“DH INSTRUMENTS, INC RPM4 us A350K/BG15K Ver1.00 ”

See Also

Page 107

RPM4™ OPERATION AND MAINTENANCE MANUAL

ZOFFSETn

Purpose

Read or set the AutoZ pressure offset (P_offset) for the specified or active Q-RPT in the current

measurement mode.

Command

Query

“ZOFFSETn GaOffset , AbsOffset , DifOffset”

“ZOFFSETn?”

Classic

“ZOFFSETn =GaOffset , AbsOffset , DifOffset”

“ZOFFSETn”

Defaults

“ZOFFSETn = 0.0, 0.0, 0.0”

(Gauge Q-RPT)

“ZOFFSETn = 101325, 0.0, 0.0” (Absolute Q-RPT)

Optional Suffix

“n”

The active Q-RPT is assumed if no suffix is given.

‘1’ “:HI” Specify the Hi Q-RPT

‘2’ “:LO” Specify the Lo Q-RPT

Arguments

Remarks

GaOffset:

AbsOffset:

DifOffset:

The Q-RPT pressure offset (“Poffset”) for Gauge measurement mode (Pa).

The Q-RPT pressure offset for absolute measurement mode (Pa)

The Q-RPT pressure offset for differential measurement mode (Pa)

The pressure offset (P_offset) for the specified Q-RPT (Hi or Lo) can be accessed with this

program message. There are separate offsets for gauge, absolute and differential

measurement modes, but not all modes apply in all cases. Gauge Q-RPTs do not support

“AbsOffset”. “DifOffset” applies only to the “Hi” Q-RPT.

Using this program message overwrites the current offset, so caution must be used.

Changes made using this program message take effect immediately.

Example

(enhanced)

Example

(classic)

Errors

Cmd sent:

Query reply:

Sent:

“ZOFFSET1 2.1, 0, 0”

2.10 Pa, 0.00 Pa, 0.00 Pa”

“ZOFFSET=97293.1, 3.02, 0”

97293.10, 3.02, 0.00”

One of the arguments is out of range.

“

Reply:

“

ERR# 6:

3.5.1

See Also

4.5

STATUS REPORTING SYSTEM

The RPM4 status reporting system is used to track and report system status and errors. It follows the

model of the IEEE Std 488.2 and works for the COM1 and the IEEE-488 port with slight differences. The

RPM4 can be programmed to respond to various status conditions by asserting the SRQ of the IEEE-488

interface. The COM1 port cannot be supported in such a way, so polling must be used.

4.5.1

ERROR QUEUE

The RPM4 keeps track of remote errors by using an error queue. If an error occurs, it is pushed

onto the Error Queue. If you are using the COM1 port, the error number is immediately

replied in the form “ERR#nn where nn is the error code from 0 to 99. The “ERR?” (or “ERR”)

query can then be used to pull the error from the Error Queue in it’s descriptive text format.

If you are using the enhanced program message format, the Error Queue will accumulate

errors until full unless they are pulled from the queue. If you are using the classic program

format, the Error Queue is cleared every time a new program message is received.

4.5.2

STATUS BYTE REGISTER

The RPM4 contains an 8 bit Status Byte Register that reflects the general status of the

RPM4.

Table 18. 8 Bit Status Byte Register

OPER

RQS/MSS

ESB

MAV

N/A

ERROR

N/A

RSR

(128)

(64)

(32)

(16)

(8)

(4)

(2)

(1)

This register is affected by the RPM4 reply output queue, the Error Queue, the Standard

Event Status register and the Ready Event Status register.

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4. REMOTE OPERATION

Status Byte Register

^(“∗STB?” or ”∗SRE n”)

OPER

(128)

Standard Event Status Register

RQS/MSS

(64)

(“∗ESR?” or “∗ESE n”)

ESB

←←←

(32)

PON

URQ

CMD

EXE

DDE

QYE

RQC

OPC

(128)

(64)

(32)

(16)

(8)

(4)

(2)

(1)

MAV

←←←

(16)

OUTPUT

QUEUE

N/A

(8)

ERROR

←←←

(4)

ERROR

QUEUE

Ready Event Status Register

N/A

(2)

(“RSR?” or ” RSE n”)

RSR

N/A

MEAS

NDRY

RDY

N/A

MEAS

NRDY

RDY

←←←

(1)

(128)

(8)

(64)

(32)

(16)

(4)

(2)

(1)

Figure 6. Status Register Schematic

The Status Byte Register can be read using the “*STB?” query, or by performing a serial poll

on the IEEE-488 bus. If you read this using a serial poll then Bit 6 is the RQS. If the

“*STB?” query is used, then bit 6 is the MSS bit. All of the other bits are common to both types

of query.

Each of these status bits can cause a SRQ to occur. The Service Request Enable Register

(“*SRE” program message ) determines which of these flags are able to assert the SRQ line.

This enable register has a matching set of bits that each will enable the designated bit to

cause a SRQ, except for the RQS/MSS bit(s) which cannot cause a SRQ. If you set this

description of these bits are given as:

OPER

RQS

N/A Bit 7 (128)

Requested Service Bit 6 (64)

Indicates that the SRQ line of the IEEE-488 interface has been asserted by the

RPM4. This bit is cleared when a serial poll is performed on the RPM4, and is a

part of the Status Byte Register when read using a serial poll. This bit does not

apply if the COM1 port is being used.

MSS

Master Summary Status Bit 6 (64)

Indicates that an event or events occurred that caused the RPM4 to request service

from the Host, much like the RQS bit. Unlike the RQS bit, it is READ ONLY and can

be only cleared when the event(s) that caused the service request are cleared.

ESB

Event Summary Bit 5 (32)

Indicates if an enabled bit in the Standard Event Status Register became set

(see Section 4.5.3).

MAV

Message Available Bit 4 (16)

Indicates that at least one reply message is waiting in the RPM4 IEEE-488 output

queue.

ERROR

RSR

Error Queue Not Empty Bit 2 (4)

Indicates that at least one command error message is waiting in the RPM4 IEEE-

488 error message queue. Use the “ERR?” query to get this message.

Ready Summary Bit 0 (1)

Indicates that an enabled bit in the Ready Status Register became set.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

4.5.3

STANDARD EVENT REGISTER

The RPM4 contains an 8 bit Standard event register that reflects specific RPM4 events.

Enabled events in this register will set or clear the ESB bit of the Status Byte Register.

Table 19. 8 Bit Standard Event Register

PON

URQ

CMD

EXE

DDE

QYE

RQC

OPC

(128)

(64)

(32)

(16)

(8)

(4)

(2)

(1)

This register can be read using the “*ESR?” query, Each of these status bits can set the ESB

bit of the Status Byte Register, causing a SRQ to occur IF the ESB bit is enabled to do so.

The Standard Event Status Enable Register (“*ESE” program message ) determines which of

these flags are able to assert the ESB bit. The description of these bits are given as:

PON

URQ

CMD

EXE

DDE

QYE

Power On Bit 7 (128)

Indicates that the RPM4 power has been cycled since the last time this bit was

read or cleared.

User Request Bit 6 (64)

Indicates that the RPM4 was set to local operation manually from the front panel

by the user (pressing the [ESC] key).

Command Error Bit 5 (32)

Indicates that a remote command error has occurred. A command error is

typically a syntax error in the use of a correct program message.

Execution Error Bit 4 (16)

Indicates if a remote program message cannot be processed due to device

related condition.

Device Dependent Error Bit 3 (8)

Indicates that an internal error has occurred in the RPM4 such as a transducer time-

out.

Query Error Bit 2 (4)

Indicates that an error has occurred in the protocol for program message

communications. This is typically caused by a program message being sent to

the RPM4 without reading a waiting reply.

RQC

OPC

Request Control Bit 1 (2)

This bit is not supported as the RPM4 cannot become the active controller in charge.

Operation Complete Bit 0 (1)

Indicates that the RPM4 has completed all requested functions.

4.5.4

READY STATUS REGISTER

The RPM4 contains an 8 bit Ready Status Register that reflects specific RPM4 Q-RPT

measurement ready events. Enabled events in this register will set or clear the RSB bit of

the Status Byte Register.

Table 20. 8 Bit Ready Status Register

N/A

MEAS

NRDY

RDY

N/A

MEAS

NRDY

RDY

(128)

(8)

(64)

(32)

(16)

(4)

(2)

(1)

Page 110

4. REMOTE OPERATION

This register can be read using the “*RSR?” query, Each of these status bits can set the

RSB bit of the Status Byte Register, causing a SRQ to occur IF the RSB bit is enabled to do so.

The Standard Event Status Enable Register (“*RSE” program message ) determines which

of these flags are able to assert the RSB bit. The description of these bits are given as:

MEAS LO Lo-RPT measurement ready Bit 6 (64)

Indicates that the Hi Q-RPT has completed a Q-RPT measurement.

NRDY LO Lo Q-RPT pressure Not Ready Bit 5 (32)

Indicates that the Hi Q-RPT made a transition from Ready to Not Ready as

defined by the stability settings (see Section 3.2.1).

RDY LO

Lo Q-RPT pressure Ready Bit 4 (16)

Indicates that the Hi Q-RPT is Ready as defined by the stability settings (see

Section 3.2.1).

MEAS HI Hi Q-RPT measurement ready Bit 2 (4)

Indicates that the Hi Q-RPT has completed a Q-RPT measurement.

NRDY HI Hi Q-RPT pressure Not Ready Bit 1 (2)

Indicates that the Hi Q-RPT made a transition from Ready to Not Ready as

defined by the stability settings (see Section 3.2.1).

RDY HI

Hi Q-RPT pressure Ready Bit 0 (1)

Indicates that the Hi Q-RPT is Ready as defined by the stability settings (see

Section 3.2.1).

4.6

IEEE STD. 488.2 COMMON AND STATUS PROGRAM

MESSAGES

The RPM4 supports a set of commands that are common to all instruments conforming to IEEE Std. 488.2.

These command make it easy to perform basic function for any device that supports these commands.

These commands also cover the status reporting commands. See Section 4.5 for details on the status

registers mentioned in these commands.

Table 21. Program Message List

Clear all of the status & event structures.

∗CLS

∗ESE

∗ESR

∗IDN

Read or set the Standard Event Status Enable Register.

Read the Standard Event Status Register.

Identify the RPM4 version, range, and serial number.

Set the operation complete bit when all operations have completed.

Read the list of installed RPM4 options.

∗OPC

∗OPT

∗RST

∗TST

∗SRE

∗STB

∗RSE

∗RSR

Reset the RPM4 settings to factory settings.

Read the power on self test status.

Read or set the Service Request Enable Register.

Read the Status Byte Register.

Read or set the Ready Status Enable Register.

Read the Ready Status Register.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

4.6.1

PROGRAM MESSAGE DESCRIPTIONS

∗CLS

Purpose

Command

Remarks

Clear all of the status & event structures.

“∗CLS”

This program message clears the following events and status registers:

Standard Byte Register (STB)

Standard Event Status Register (ESR)

Error Queue

Pending OPC operations

Example

Sent:

Reply:

“∗CLS”

none

∗ESE

Purpose

Command

Query

Read or set the Standard Event Status Enable Register.

“∗ESE n”

“∗ESE?”

“∗ESE 0”

Default

Arguments

’0 to 255’ This is the decimal representation of the bit(s) to enable. To enable

the PON and QYE bits, the argument would be 128 + 4 = 132.

Remarks

The Standard Event Status Enable register determines which bits in the standard Event

Status Register are enabled and included in the Status Byte Register (ESB bit), and can

assert the SRQ line. The reply is in decimal numeric form.

Example

(enhanced)

Errors

Sent:

Query reply:

ERR# 6:

“∗ESE=128”(enables the PON bit)

“128” (no reply if IEEE-488)

n is not valid.

∗ESR

Purpose

Command

Remarks

Read the Standard Event Register.

“∗ESR?”

The Standard Event Register contents are cleared after reading. The reply is in decimal

numeric form.

Example

(enhanced)

Sent:

Reply:

“∗ESR?”

“20” (the QYE and EXE bits are set)

∗IDN

Purpose

Query

Identify the RPM4 version, range, and serial number.

“∗IDN?”

Remarks

The identification reply is made up of the manufacture, the model, the serial number and the

software version. Each is separated by a comma.

Sent:“∗IDN?”

Example

(enhanced)

Reply:“DH INSTRUMENTS INC, RPM4 A0100/A0015, 1234, Ver2.00 -dhf”

∗OPC

Purpose

Command

Query

Sets the operation complete bit when all operations have completed.

“∗OPC”

“∗OPC?”

Remarks

This Command enables the RPM4 to set the OPC bit in the Standard Event Status Register

when it has completed all pending functions.

The Query replies with a “1” when all functions are complete.

Example

(enhanced)

Sent:

Query reply:

“∗OPC”

“1”

∗OPT

Purpose

Reads the list of installed RPM4 options.

Query

“∗OPT?”

Remarks

This Query returns any registered option(s) installed in the RPM4. Each option is separated

by a comma. Possible options:

“IEEE-488:0”

The IEEE-488 option is installed,

Example

(enhanced)

Sent:

Reply:

“∗OPT?”

“IEEE-488:0”

∗RST

Purpose

Command

Remarks

Resets the RPM4 settings to factory settings.

“∗RST””

This Command sets the RPM4 settings to factory settings. This equivalent to a front panel

executed RESET/SET. This does not affect the communications settings.

Example

(enhanced)

Sent:

Reply:

“∗RST”

“∗RST” (no reply if IEEE-488)

See Also

Section 3.5.4.1, Reset – Sets

Page 112

4. REMOTE OPERATION

∗SRE

Purpose

Command

Query

Read or set the Service Request Enable Register.

“∗SRE n”

“∗SRE?”

“∗SRE 0”

Default

Arguments

’0 to 255’ This is the decimal representation of the bit(s) to enable. To allow the

MAV and ESB bits to assert the SRQ line, the argument would be 32 + 16 = 48.

Bit 6 (64) is reserved and cannot be set.

Remarks

The Service Request Enable Register determines which bits of the Status Byte can set the MSS

bit of the Status Byte and request service by asserting the SRQ line of the IEEE-488 interface.

Example

(enhanced)

Errors

Sent:

Query reply:

ERR# 6:

“∗SRE=48” (enables the MAV and ESB bits)

“48” (no reply if IEEE-488)

n is not valid.

∗STB

Purpose

Command

Remarks

Read the Status Byte Register.

“∗STB?”

The Status Byte Register reflects the general status of the RPM4. The ‘MSS’ bit state is

represented by bit 6.

Example

(enhanced)

Sent:

Reply:

“∗STB?”

“80” (The MSS and MAV bits are set)

∗TST

Purpose

Read the power on self test status.

Query

“∗TST?””

Remarks

The RPM4 system memory stores the user settings (units, resolution) and retains them when

the unit if OFF. On power-up, this memory is checked. If this memory is corrupted, all user

settings are reset to default (as if the “∗RST” program message was executed), and the ∗TST

query will return a non zero value. If the RPM4 passed the test on power-up OR if the ∗TST

query was used at least once since the RPM4 was powered up the reply will be a ‘0’.

Example

(enhanced)

Sent:

Reply:

“∗RST?”

“1”

*RSE

Purpose

Command

Query

Read or set the Ready Status Enable Register.

“RSE n”

“RSE?”

“RSE 0”

Default

Arguments

Remarks

’0 to 255’ This is the decimal representation of the bit(s) to enable. To enable

the RDY bit, the argument would be 1.

The Ready Status Enable Register determines which bits in the Ready Status Register are

enabled and included in the Status Byte Register (RSR bit), and can assert the SRQ line.

The reply is in decimal numeric form.

Example

(enhanced)

Errors

Sent:

Query reply:

ERR# 6:

“∗RSE=1” (enables the RDY bit)

“1” (no reply if IEEE-488)

n is not valid.

*RSR

Purpose

Command

Remarks

Read the Ready Status Register.

“RSR?”

The Ready Status Register contents are cleared after reading. The reply is in decimal

numeric form.

Example

Sent:

“RSR?”

(enhanced)

Reply:

“6” (The MEAS and NRDY)

Page 113

RPM4™ OPERATION AND MAINTENANCE MANUAL

NOTES

Page 114

5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

5. MAINTENANCE,

ADJUSTMENTS AND CALIBRATION

5.1

OVERVIEW

RPM4 was designed for maintenance free operation. No maintenance is required other than:

•

Regular AutoZeroing of quartz reference pressure transducer(s) (Q-RPT) (see Section 3.5.1).

Periodic calibration of Q-RPT(s) (see Section 5.2).

Adjustment of the on-board barometer, if present (see Sections 5.3).

This section provides information on maintenance, adjustment and calibration procedures, and recommended

overhaul procedures.

RPM4 is a sophisticated pressure measuring instrument with advanced on-board features and

functions. Before assuming that unexpected behavior is caused by a system defect or breakdown, use

this manual and other training facilities to become thoroughly familiar with RPM4 operation.

For rapid assistance in specific situations see Chapter 6 for troubleshooting information.

RPM4 is covered by a limited one (1) year warranty. Unauthorized service or repair during the warranty

period is undertaken at the owner’s risk and may cause damage that is not covered under warranty

and/or may void the warranty. For warranty service, contact a DHI Authorized Service Provide (see

Table 29).

5.2

CALIBRATION OF QUARTZ REFERENCE PRESSURE

TRANSDUCERS (Q-RPTS)

5.2.1

PRINCIPLE

RPM4 is equipped with one or two quartz reference pressure transducers (Q-RPTs)

used for low uncertainty pressure measurement.

To calibrate a Q-RPT, pressures from a reference standard are applied to the Q-RPT at

ascending and descending pressure increments over the range. The recommended

pressure sequence for a calibration varies depending on whether the Q-RPT is of Standard or

Premium class (see Section 1.2.2.1). The pressure defined by the standard and the

corresponding Q-RPT readings are recorded at each point. After all of the pressures have

been applied and recorded, adjustments are made to fit the Q-RPT pressure readings to the

standard. Fitting the readings means performing a linear regression to arrive at the lowest

value of the residuals of errors of the Q-RPT relative to the standard. The Q-RPT output is

adjusted by user settable coefficients: PA (an adder or offset) and PM (a multiplier or span

set) (see Section 5.2.1.1).

Page 115

RPM4™ OPERATION AND MAINTENANCE MANUAL

The calibration process is performed independently on each Q-RPT to arrive at its optimal fit.

CalTool for RPTs software provided with the RPM4 supports the calibration process of

RPM4 Q-RPTs. CalTool and its documentation are provided on a General Accessories Disk with a

new RPM4 and can be downloaded from www.dhinstruments.com. Most users should use

CalTool software to assist in the calibration of RPM4.

RPM4 is delivered with an interactive Q-RPT calibration utility that steps the operator through

the complete Q-RPT calibration procedure including applying the necessary pressures,

collecting data automatically, calculating new PA and PM values, previewing the results of

the new calibration and activating the results of the new calibration (see the CalTool for RPTs

manual on the General Accessories Disk). RPM4 also provides complete front panel and

remote access to Q-RPT calibration parameters so that Q-RPT calibrations can be performed

without using CalTool software (see Section 5.2.8).

5.2.1.1

PA AND PM COEFFICIENTS

The coefficients used to adjust Q-RPT readings are designated PA (an adder or

offset) and PM (a multiplier or span set). The coefficients affect the Q-RPT

reading following:

Corrected reading = (uncorrected reading • PM) + PA

PA is expressed in units of pressure (always the SI unit, Pascal).

PM is dimensionless.

Each Q-RPT has its own unique PA and PM values. The PA and PM values

currently in use can be viewed and edited from the front panel in the CAL

function (see Section 5.2.7). PA and PM values are automatically edited when

CalTool software results are activated.

As editing PA and PM values will change Q-RPT calibration, they should only

be edited by qualified personnel as part of the calibration process. Caution

should be taken to avoid accidental editing and a security system is

available to prevent access (see Section 3.5.5.5). Incorrect editing of PA

and PM values can cause out of tolerance measurements.

A new RPM4 is delivered with PA and PM values set to zero and 1 for all

ranges. This does not mean that the RPM4 has not been calibrated. In the

original factory calibration, privileged factory coefficients are used for

calibration with the user PA and PM set to zero and 1.

5.2.1.2

AS RECEIVED AND AS LEFT DATA

Frequently, calibration procedures require that as received and as left data be

reported. The necessary information to report as received and as left data on the

calibration of RPM4 Q-RPTs can be obtained in several ways.

When the RPM4 CalTool calibration assistance software is used, as received

data is displayed while running the calibration and is automatically recorded and

reported if desired. As left data is also calculated and presented.

At any time, a) reference pressures applied; b) associated Q-RPT readings;

c) PA and PM and P_offsetvalues, can be used to calculate as received and as left values.

For example, backing out PA and PM on the as left data yields the Q-RPT

Page 116

5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

readings with PA = 0 and PM = 1. Then applying the as received PA and PM

and P_offsetvalues to the readings calculates as received readings (the readings

that the transducer would have made with the old PA, PM and P_offset).

It is recommended that “as received” values of PA, PM and P_offset(for Axxx

Q-RPTs if absolute mode AutoZero is used in normal operation) be recorded for

each Q-RPT prior to running the calibration. The current PA, PM and P_offset(for

Axxx Q-RPTs) can be viewed by pressing [SPECIAL], <8cal>, <1view>.

5.2.2

EQUIPMENT REQUIRED

The recommended calibration standards for RPM4 Q-RPTs are DHI PG7000 piston

gauges (PG7102, PG7202, PG7601 for gas; PG7302 for oil). Contact DHI for additional

information.

5.2.2.1

GAS OPERATED Q-RPTS, A10M AND LOWER

Gas operated piston gauge (deadweight tester), with the following

characteristics:

•

Measurement uncertainty of ± 0.0025 % of reading for Standard Class

Q-RPTs or ± 0.002 % of reading for Premium Class Q-RPTs. A standard

with higher measurement uncertainty may be used but RPM4 measurement

uncertainty may be degraded proportionally from published specifications.

•

If the Q-RPT is Axxx (absolute) and will be used in the absolute and/or

negative gauge measurement modes, the reference must be able to apply

absolute pressures: Absolute pressures may be defined either by operation

relative to an evacuated bell jar or, for higher pressures, by addition of

atmospheric pressure measured by a suitable barometer. Axxx (absolute)

Q-RPTs that will not be used in absolute or negative gauge

measurement modes (as is often the case for higher pressure Q-RPTs)

do not require the application of absolute pressure for calibration and

may be calibrated using a gauge pressure standard.

Axxx (absolute) Q-RPTs calibrated in gauge measurement mode by

applying gauge reference pressure values should be used in gauge mode

only (see Sections 3.3.3, PRINCIPLE, 5.2.5).

•

Able to supply the recommended sequence of pressure points in the

range to be calibrated:

See Section 5.2.4 for information on the

recommended calibration point sequence for various Q-RPT types

and classes.

5.2.2.2

OIL OR GAS OPERATED Q-RPTS A14M AND HIGHER

Gas or oil operated piston gauge (deadweight tester), with the following

characteristics:

Do not put oil or other liquids in a Q-RPT that is meant to be operated

with gas.

Page 117

RPM4™ OPERATION AND MAINTENANCE MANUAL

•

Measurement uncertainty of ± 0.008 % of reading for Standard Class

Q-RPTs or ± 0.005 % of reading for Premium Class Q-RPTs. A standard

with higher measurement uncertainty may be used but RPM4 measurement

uncertainty may be degraded proportionally from published specifications.

If the Q-RPT is Axxx (absolute) and will be used in the absolute and/or

negative gauge measurement modes, the reference must be able to apply

absolute pressures: Absolute pressures may be defined by adding

atmospheric pressure measured by a barometer to gauge pressure defined by a

piston gauge. Axxx (absolute) Q-RPTs that will not be used in absolute or

negative gauge measurement modes (as is very often the case for higher

pressure Q-RPTs) do not require the application of absolute pressure

for calibration and may be calibrated using a gauge pressure standard.

Axxx (absolute) Q-RPTs calibrated in gauge measurement mode by

applying gauge reference pressure values should be used in gauge mode

only (see Sections 3.3.3, PRINCIPLE, 5.2.5).

•

Able to supply the recommended sequence of pressure points in the

range to be calibrated:

See Section 5.2.4 for information on the

recommended calibration point sequence for various Q-RPT types and

classes.

5.2.3

SET-UP AND PREPARATION

To set-up and prepare an RPM4 for calibration of a Q-RPT:

Set the RPM4 on a stable surface near the calibration standard at a height as close as

possible to the calibration standard’s reference height. Consider the connections that

may need to be made to the rear panel and access to the front panel display and keypad.

Connect the calibration standard output to the TEST(+) port of the Q-RPT module to be

calibrated on the RPM4 rear panel (1/8 in. NPT F or DH500F depending on range, see

Section 2.3.5).

If the Q-RPT module has a TEST(-) port, leave it unobstructed or connect it to the

reference standard’s TEST(-) port if available.

Open SDS (Self Defense System) if present (see Section 3.3.8) for the Q-RPT to be

calibrated. When the RPM4 indicates <SDS CLOSED>, the TEST(+) port is isolated from

the Q-RPT to be calibrated.

Opening SDS with a pressure greater than Pmax! applied to the test port may cause

overpressure damage to the Q-RPT.

The Q-RPTs of RPM4s used in parallel measurement mode must be adjusted separately.

PA and PM for the Hi and Lo Q-RPT need to be determined and set individually. Therefore,

data to be used in determining calibration coefficients cannot be taken in parallel mode

(see Section 3.5.7.3). Do not run a calibration with the HL (parallel mode) Q-RPT active.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

5.2.4

RECOMMENDED CALIBRATION POINT SEQUENCE

Calibration adjustments to RPM4 Q-RPTs are made by altering calibration coefficients,

PA and PM (see Section 5.2.1.1). To adjust these coefficients to optimum values giving the

best results over the Q-RPTs complete operating range, specific calibration point sequences

are recommended. The recommended point sequence depends upon whether the Q-RPT

being calibrated is a Standard or Premium Class (see Section 1.2.2.1). The class of the

RPM4 Q-RPTs is indicated in the model number on the product label and on the rear panel

Q-RPT label (<s> for standard, <p> for premium, for example A7Ms or A7Mp).

Prior to running the calibration point sequence, the Q-RPT should be exercised by:

a) Setting full scale pressure.

b) Dwelling at full scale pressure for 5 minutes.

c) Returning to atmospheric pressure (vented). If the Q-RPT is a gas operated Axxx type,

use vacuum rather than atmospheric pressure.

d) Dwelling for twenty minutes.

A dwell time after setting the pressure of at least 60 seconds before taking data at each point

is recommended.

Section 5.2.4.1 gives calibration point sequences for Standard Class Q-RPTs and Section 5.2.4.2

gives calibration point sequences for Premium Q-RPTs.

It is not required that the calibration pressure standard apply precisely the nominal

pressure value of each calibration point as long as the exact value of the applied pressure

is known. Best results are obtained if the actual applied pressure is within 2 % of the

recommended nominal point.

5.2.4.1

STANDARD CLASS Q-RPTS

See additional information in Section 5.2.4 concerning exercising the Q-RPT and

dwell time at pressure points.

Table 22. Calibration Point Sequence, Standard Class,

Axxx and Gxxx Q-RPTs

CALIBRATION

SEGMENT

POINT

NO.

POINT

[% OF SPAN]

Lowest Pressure¹

25 %

Ascending

50 %

75 %

100 %

75 %

50 %

Descending

25 %

Lowest Pressure¹

1. In absolute mode, the lowest point that can be set reliably by

the reference piston gauge, or atmospheric pressure for ranges

> A1.4M. Zero (vented) in gauge mode.

Axxx (absolute) Q-RPTs that will NOT be used in absolute or

negative gauge measurement modes may be calibrated in

gauge measurement mode with a gauge pressure standard.

Axxx (absolute) Q-RPTs calibrated in gauge measurement

mode should be used in gauge mode only (see Sections 3.3.3,

PRINCIPLE, 5.2.5).

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Table 23. Calibration Point Sequence, Standard Class,

BGxxx Q-RPTs

CALIBRATION

SEGMENT

POINT

NO.

POINT

[% OF SPAN]¹

0 %

25 %

50 %

75 %

100 %

75 %

50 %

25 %

0 %

Ascending

Descending

1. The BG15K span is

–

15 to

15 kPa, 30 kPa total.

Therefore, 0 % is – 15 kPa, 25 % is – 7.5 kPa, 100 % is

+ 15 kPa, etc.

BGxxx (bi-directional gauge) Q-RPTs that will NOT be used

in negative gauge measurement mode may be calibrated in

gauge (positive pressures) measurement mode only. Use the

Standard Class gauge mode (Gxxx) calibration point

sequence (see Table 22). BGxxx Q-RPTs calibrated in gauge

measurement mode only should not be used in negative

gauge mode.

Table 24. Calibration Point Sequence, Standard Class,

BA100K Q-RPT

CALIBRATION

SEGMENT

POINT

NO.

POINT

[% OF SPAN]¹

0 %

25 %

50 %

75 %

100 %

75 %

50 %

25 %

0 %

Ascending

Descending

The BA100K span is 70 to 110 kPa absolute.

5.2.4.2

PREMIUM CLASS Q-RPTS

See additional information in Section 5.2.4 concerning exercising the Q-RPT and

dwell time at pressure points.

Verification of Premium Class Q-RPTs

When verifying (as opposed to calibrating) a Premium Q-RPT, it is not necessary

to include the higher density of points that is recommended for determination of the

calibration coefficients. A 5 points up, 2 points down (50%, low point) run is

adequate. To verify that the uncertainty turndown with AutoRange (see Sections

3.3.4, 1.2.2.1) is in tolerance, it is recommended that the verification of a Premium

Q-RPT include verification of an AutoRanged span of 30 % of the maximum

Q-RPT span. For example, verify an A7M Q-RPT in the default range of 0 to 7 MPa

(1 000 psi) and in the AutoRange range of 2.1 MPa (300 psi).

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

Table 25. Calibration Point Sequence, Premium Class,

Axxx and Gxxx Q-RPTs

CALIBRATION

SEGMENT

POINT

NO.

POINT

[% OF SPAN]

Lowest Pressure¹

5 %

10 %

15 %

20 %

Ascending

30 %

40 %

50 %

60 %

80 %

100 %

80 %

50 %

Descending

20 %

Lowest Pressure¹

In absolute mode, lowest point that can be set reliably by the

reference piston gauge. Zero (vented) in gauge mode.

Axxx (absolute) Q-RPTs that will NOT be used in absolute or

negative gauge measurement modes may be calibrated in

gauge measurement mode with a gauge pressure standard.

Axxx (absolute) Q-RPTs calibrated in gauge measurement

mode should be used in gauge mode only (see Section 5.2.5).

Table 26. Calibration Point Sequence, Premium Class,

BGxxx Q-RPTs

CALIBRATION

SEGMENT

POINT

NO.

POINT

[% OF SPAN]¹

0 %

15 %

30 %

40 %

45 %

50 %

55 %

60 %

70 %

85 %

100 %

70 %

50 %

30 %

0 %

Ascending

Descending

1. The BG15K span is – 15 to + 15 kPa, 30 kPa total. Therefore,

0 % is – 15 kPa, 25 % is – 7.5 kPa, 100 % is + 15 kPa, etc.

BGxxx (bi-directional gauge) Q-RPTs that will not be used in

negative gauge measurement mode may be calibrated in

gauge (positive pressures) measurement mode only. Use the

Premium Class gauge mode (Gxxx) calibration point sequence

(see Table 25).

BGxxx Q-RPTs calibrated in gauge

measurement mode only should not be used in negative

gauge mode.

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5.2.5

TURNING OFF ABSOLUTE AND NEGATIVE GAUGE

MEASUREMENT MODES FOR AXXX (ABSOLUTE) Q-RPTS

PURPOSE

To prevent operation in absolute and negative gauge measurement modes on an Axxx

(absolute) Q-RPT that has been calibrated for gauge mode only.

PRINCIPLE

Axxx (absolute) Q-RPTs are frequently used in gauge measurement mode only (see Section

3.3.3, PRINCIPLE). Axxx Q-RPTs that are used in gauge mode only, may be calibrated in

gauge mode with a reference that applies gauge pressures. Calibration with an absolute

reference is not necessary. However, if an Axxx Q-RPT is calibrated in gauge mode, it is not

possible to know if it is in or out of tolerance in absolute and negative gauge modes. To avoid

using absolute and negative gauge measurement modes with an Axxx Q-RPT that is

calibrated for gauge mode only, access to absolute and negative gauge modes can be turned

OFF. This is accomplished in the [SPECIAL], <8cal> menu.

OPERATION

See Section 5.2.7 for more detailed information on editing and viewing Q-RPT calibration

information.

Turning absolute and negative gauge mode operation ON and OFF for a Q-RPT occurs in the

same area in which calibration coefficients are edited. To access the Q-RPT calibration editing area

press [SPECIAL], <8cal> and select the desired Q-RPT. Then select <1edit> to make changes.

Allow abs and

[ENT] through the calibration information screens.

After viewing the values of PA and PM the display is:.

neg g mode? 1yes 2no

The cursor is on the number corresponding to the current selection. Make the desired selection.

<1no> causes absolute and negative gauge modes to be unavailable for the Q-RPT.

5.2.6

5.2.7

Q-RPT CALIBRATION USING CALTOOL FOR RPTS

SOFTWARE

To calibrate RPM4 Q-RPTs using CalTool software, refer to Sections 5.2.1,

PRINCIPLE, 5.2.2, and 5.2.3 in this manual and then refer to the CalTool for

RPTs Software Manual.

CalTool for RPTs software and manual are supplied on the RPM4

General Accessories Disk and can be downloaded from www.dhinstruments.com.

EDITING AND VIEWING Q-RPT CALIBRATION

INFORMATION

PURPOSE

View and/or edit Q-RPT calibration information fields including:

•

The calibration date – This field is normally used to record the date on which the Q-RPT

is calibrated.

•

The value of absolute mode AutoZero P_offset(Axxx Q-RPTs only) – See Section 3.5.1

for complete AutoZero information. This value is normally set to zero following absolute

measurement mode calibration of an Axxx Q-RPT.

•

The value of PA – The pressure adder for the selected Q-RPT (see Sections 5.2.1.1).

The value of PM – The pressure multiplier for the selected Q-RPT (see Sections 5.2.1.1).

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

•

Absolute and negative gauge measurement modes ON or OFF (Axxx Q-RPTs only)

– See Section 3.3.3, PRINCIPLE for complete information on measurement modes.

This is set to OFF if an Axxx Q-RPT was calibrated in gauge mode with a gauge

pressure standard.

OPERATION

As editing PA and PM values will change the calibration of the Q-RPTs, the edit function

should only be used by qualified personnel as part of the calibration process. Caution

should be taken to avoid accidental editing. A user level security system is available to

control access (see Section 3.5.5.5).

A new RPM4 is delivered with PA and PM values set to zero and 1 for all ranges. This does

not mean that the RPM4 has not been calibrated. In the original factory calibration, privileged

factory coefficients are used for calibration with the user PA and PM set to zero and 1.

To access Q-RPT calibration information viewing or editing press [SPECIAL], <8Cal>.

Select the desired Q-RPT. The <1view> selection displays the calibration information fields.

The <2edit> function displays the fields and allows them to be edited. The display is:

1. Date of last calibration in YYYYMMDD format.

Cal date:20030325 Hi

AbsPoffset: 0.0 Pa

2. Position designator of the Q-RPT being viewed.

3. Current value of absolute mode P_offset

This line is blank if the Q-RPT is not an Axxx type.

If in edit mode, the calibration information fields can be edited. Edits to P_offsetare common

with changes made in the AutoZ edit or run function (see Section 3.5.1). Pressing [ENT] on

the last field goes to the next view/edit screen:

1. Value of PA.

PA: 0.0 Pa

2. Position designator of the Q-RPT being viewed.

3. Value of PM.

PM: 1.000000

If in edit mode, the calibration fields can be edited. If the selected Q-RPT is an Axxx Q-RPT,

pressing [ENT] in the PM field goes to the next calibration information display (this display is

skipped if the Q-RPT is a Gxxx or BGxxx type):

1. Position designator of the Q-RPT being viewed.

Absolute and

2. Cursor is on current ON or OFF selection.

neg g mode: 1on 2off

The cursor is on the current setting. If in edit mode, the ON or OFF status can be changed

by selecting <1on> or <2off> (see Section 5.2.5). [ENT] in view mode returns to the

view/edit screen. [ENT] in edit mode goes to confirmation of change activation if changes have

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RPM4™ OPERATION AND MAINTENANCE MANUAL

been made in any of the calibration screens. Pressing [ESC] in any edit screen exits the edit screen

without activating any changes.

The value of PA is always in Pascal (Pa). The value of PM is dimensionless.

5.2.8

Q-RPT CALIBRATION/ADJUSTMENT WITHOUT CALTOOL

FOR RPTS SOFTWARE

PRINCIPLE

The RPM4 Q-RPTs can be calibrated and adjustments made without using CalTool for RPTs

software. This requires:

•

Applying pressures with a calibration standard and recording the pressures measured by RPM4.

Calculating new PA and PM values and entering them.

Setting P_offsetto zero for Axxx Q-RPTs.

Before proceeding to calibrate a reference pressure transducer without using CalTool for RPTs

software, Sections 5.2, Calibration of Reference Pressure Transducers, 5.2.1 PRINCIPLE,

5.2.2 Equipment Required, 5.2.3 Setup and Preparation should be reviewed thoroughly.

The Q-RPTs of RPM4s used in parallel measurement mode must be adjusted separately.

PA and PM for the Hi and Lo Q-RPT need to be determined and set individually. Therefore,

data to be used in determining calibration coefficients cannot be taken in parallel mode

(see Section 3.5.7.3).

OPERATION

The typical procedure for calibrating a Q-RPT is:

Set-up and prepare the RPM4 for calibration (see Sections 5.2.2, 5.2.3).

Use the [RANGE] function key to select the Q-RPT to be calibrated (see Section 3.3.1).

Be sure to set the DF range (not an AutoRanged range).

Use [HEAD] to set the HEAD to zero (see Section 3.3.7). Use [UNIT] to set the desired

pressure unit of measure (see Section 3.3.2). Use [MODE] to set the desired pressure

measurement mode (see Section 3.3.3). Axxx (absolute) Q-RPTs that will be used in

gauge measurement mode only, may be calibrated in gauge measurement mode with a

gauge pressure standard (see Section 5.2.5).

Use [SPECIAL], <1AutoZ> to access the AutoZ function (see Section 3.5.1).

If calibrating in absolute measurement mode, turn AutoZ ON if it is left ON in normal

RPM4 operation.

If calibrating in gauge measurement mode, always turn AutoZ ON.

Use [SPECIAL], <8cal>, <1Hi RPT> or <2Lo RPT>, <1view>, to read and record the

current values of PA and PM for the Q-RPT to be calibrated. If calibrating in absolute mode,

also record the value of P_offset

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

Run the recommended calibration point sequence for the Q-RPT (see Section 5.2.4).

Record the pressure applied by the standard and the RPM4 reading at each calibration

point. Dwell at least 60 seconds at each point after setting the reference pressure to

allow full stabilization The data recorded is the “as received” data for this calibration.

Enter the calibration pressures and RPM4 readings into a spreadsheet. Calculate the

“non-corrected” RPM4 readings by backing out the PA, PM and P_offset(P_offsetin the case of

Axxx (absolute) Q-RPTs in absolute mode only, do not back out P_offsetfor for gauge mode

calibrations) recorded in Steps and above, following:

non-corrected reading = ((corrected reading - PA)/PM ) + P_offset

Perform a linear regression to find the offset and slope that best fit the non-corrected

RPM4 readings to the calibration standard pressures. The offset is the new value of PA,

the slope is the new value of PM.

Press [SPECIAL], <8Cal>, <1Hi RPT> or <2Lo RPT>, <2edit> and write the new

calibration date and the new values of PA and PM for the Q-RPT calibrated (see Section

5.2.7). If this is an Axxx Q-RPT and the calibration was performed in gauge mode, turn

absolute and negative gauge modes OFF to avoid their being used after the calibration.

Calculate as left data for the calibration if desired following:

as left reading = (non-corrected reading • new PM) + new PA

Perform additional verification pressure runs as desired.

5.3

ADJUSTMENT OF ON-BOARD BAROMETER

PURPOSE

To adjust the output of the on-board barometer (see Section 1.2.2.2).

RPM4’s that have only G100K or G200K Q-RPTs (no Axxx or G15K or BGxxx) are NOT equipped with an

on-board barometer.

PRINCIPLE

The on-board barometer output can be adjusted using PA and PM values in the same manner as

Q-RPTs (see Section 5.2.1.1).

The on-board barometer is a low accuracy sensor used only for measuring changes in atmospheric

pressure over short periods of time (see Section 3.2.2) and the line pressure for G15KK and BG15K

line pressure compensation. RPM4 measurement uncertainty does not depend on the measurement

uncertainty of the on-board barometer.

OPERATION

To edit the values of PA and PM for the barometer, press [SPECIAL], <8cal>, <3barometer>. Pressing

[ENT] steps through displays of the calibration date (YYYYMMDD) and PA and PM. In edit mode, the

values can be edited. Pressing [ENT] after the last screen activates the edited values.

To view the current output of the on-board barometer, press [SPECIAL], <7Internal>, <3baro>.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

5.4

RELOADING EMBEDDED SOFTWARE INTO FLASH

MEMORY

RPM4 uses FLASH memory. This allows the embedded software that controls RPM4 operations and

functions to be loaded into RPM4 over its COM1 port from a computer with a simple FLASH loading utility

program.

To replace corrupted software or upgrade your software, access the DHI worldwide web site at

www.dhinstruments.com and go to SOFTWARE. A FLASH loading utility and the latest RPM4

software are available for download at no charge. If you do not have access to the web or have difficulty

downloading or loading software, contact your DHI representative or a DHI Authorized Service Provider

(see Table 29) for assistance.

If you believe you have discovered an error or “bug” in RPM4 software, please report it with complete

details by email to [email protected] or submit an on-line Quality Feedback Report

under CALIBRATION & REPAIR at www.dhinstruments.com.

The DHI flash software loading utility and RPM4 embedded software are available for download from

www.dhinstruments.com in the SOFTWARE section.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

5.5

SUBASSEMBLY DESCRIPTION AND LOCATION

1. Micro Card

3. Driver Board

6. Hi Q-RPT module

(< A7M style shown)

2. Power Supply Module

(beneath Driver Board)

4. On-Board Barometer (if present)

7. Display

5. Lo Q-RPT module (if present)

(< A7M style shown)

Figure 7. Internal View

5.5.1

MINI MICRO BOARD

The micro board supports a Motorola 68302 micro-controller, EPROM, EEPROM, 128k x 16

bit NVRAM, 8 Mbit flash memory; RS-232 and IEEE-488.2 communications; keypad and

display control. An I/O port controls other ports and devices in RPM4.

5.5.2

POWER SUPPLY MODULE

+ 12 V DC (± 2 %) @ 2.1 Amps

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RPM4™ OPERATION AND MAINTENANCE MANUAL

5.5.3

DRIVER BOARD

The driver board is controlled by the mini micro board (see Section 5.5.1). It supports:

•

12 V drivers for internal solenoid valve actuation

Frequency counters (2) for reading Q-RPTs (see Section 5.5.5)

On-board barometer power and output (see Section 5.5.4)

Utility sensor (if present) power and output

Power to the system cooling fan

Remote [ENT]

Keypad and display

Beeper

5.5.4

ON-BOARD BAROMETER

The on-board barometer supports a board mounted, barometric range, micromachined

silicon sensor and an ambient temperature sensor. The barometer readings are used for

dynamic atmospheric pressure compensation when measuring gauge pressure with an

absolute quartz reference pressure transducer (see Section 3.2.2). The temperature sensor

is used for temperature compensation of the barometric sensor.

RPM4s that have only G100K or G200K Q-RPTs (no Axxx or G15K or BGxxx) are NOT

equipped with an on-board barometer.

5.5.5

Q-RPT MODULE

The Q-RPT module is an integrated Quartz Reference Pressure Transducer (Q-RPT)

assembly. The module includes a Q-RPT, brackets to hold the transducer, interconnecting

tubing, a manifold with TEST(+),TEST(-) (A70M and lower only) and VENT (ATM on A100M

and higher) ports and SDS (Self Defense System) solenoid valves (A7M and lower, gas

operated, only).

A Q-RPT provides very high precision, low uncertainty pressure measurement. The basic

sensing principle is the measurement of the change in the natural oscillating frequency of a

quartz tuning fork in response to changes in temperature and mechanical stress resulting

from the change in pressure applied to a connecting bellows or bourdon tube. Two independent

quartz elements are used. One quartz element is subjected to pressure related stress. The

other quartz element is used only to monitor temperature. See Section 1.2.2.1 for Q-RPT

specifications.

See Figure 8 for pneumatic schematics of different Q-RPT module configurations.

5.5.5.1

HI Q-RPT MODULE

RPM4 is always equipped with a Hi Q-RPT module. The Hi Q-RPT module is in

the Hi Q-RPT position. It is always the higher range in two Q-RPT RPM4s.

5.5.5.2

LO Q-RPT MODULE

RPM4 may be equipped with a Lo Q-RPT module. The Lo Q-RPT provides a

lower measurement range than the Hi Q-RPT. See Section 1.2.2.1 for complete

Q-RPT specifications.

5.5.6

DISPLAY

2 x 20 character vacuum fluorescent display.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS

5.6

Q-RPT MODULE PNEUMATIC SCHEMATICS

Axxx Q-RPT >A10M

(No SDS)

Axxx Q-RPT <A10M

VALVE

STATE

CONDITION

SDS Open

SDS Closed

Power off

Gxxx or BGxxx Q-RPT

VALVE

STATE

CONDITION

SDS Open

SDS Closed

Power off

Figure 8. Pneumatic/hydraulic schematics of RPM4 with Single Q-RPT Module

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RPM4™ OPERATION AND MAINTENANCE MANUAL

The pneumatic schematic for RPM4’s with two Q-RPT modules is the same as for the single Q-RPT

modules in Figure 8 with the following exceptions:

•

If both modules use the barometer, the barometer is connected to teed to both module barometer

connection points.

An exception is the combination of an Axxx with SDS (<A10M) and a G15K or BGxxx shown below.

Axxx Q-RPT <A10M with G15K or

BGxxx

Figure 9. Pneumatic/hydraulic schematics of RPM4 with Two Q-RPT Modules

Page 130

6. TROUBLESHOOTING

RPM4 is a sophisticated pressure setting and measuring instrument with advanced on-board features

and functions. Before assuming that unexpected behavior is caused by a system defect or breakdown,

the operator should use this manual and other training facilities to become thoroughly familiar with

RPM4 operation. This troubleshooting guide is intended as an aid in identifying the reason for RPM4

behavior and determining whether the behavior is due to normal operation or an internal or external problem.

Identify the symptom or unexpected behavior you are observing from the SYMPTOM list below.

A PROBABLE CAUSE is provided and a SOLUTION is proposed including references to manual

sections that provide information that may be of assistance.

Table 27. Troubleshooting Guide

SYMPTOM

Will not power up.

PROBABLE CAUSE

SOLUTION

Blown fuse.

Replace fuse.

Cannot access certain functions

>ACCESS RESTRICTED<

User level has been set that restrict access

to certain functions.

Change user level or consult system

manager. 3.5.5.5

Cycle power to clear. Please record

conditions leading up to event including

the numbers displayed when [ENT] is

pressed and report to your DHI

Displays <FATAL ERROR> or

<FATAL FAULT>.

Encountered unresolved internal software

conflict.

Authorized Service Provider. Table 29

Front panel keys seem to be

disabled.

<remote> command has been sent from a

host computer.

Send <local> command from host

computer or cycle RPM4 power. 4, 4.4.4

Measured pressure display or

other displays have too much/not

enough resolution.

Resolution setting needs to be changed.

Change resolution setting. 3.4.2

Resolution setting is limited when

AutoRanging under 10 % of Q-RPT default

range.

Can’t increase resolution to level

desired in AutoRanged range.

Operation is normal. Table 6

Values that should be non-zero

are displayed as zero.

Resolution setting needs to be increased to

view significant digits.

Change resolution setting. 3.4.2

Keypad presses make undesired

sounds or NO sounds.

Use keypad function to set keypad

sounds as desired. 3.5.5.2

Keypad sound settings are incorrect.

Bottom line of display has

changed and you want to change

it back.

The DISPLAY function has been used to

change the display.

Use [DISPLAY] to set bottom line to

desired display. 3.3.6

Second line of display is

and front keypad is locked out.

The RPM4 has been initialized as an

external device to a PPC3 pressure

controller and is still in external device mode.

Cycle RPM4 power to take it out of

external device mode and restore local

operation. 3.2.5

Operation is normal. Use [DISPLAY] to

change bottom line display if desired.

3.3.6

Bottom line of display is blank.

DISPLAY mode is “clean”.

The pressure units available

under the [UNIT] function key are

not the ones you want.

Use PresU function to customize the

UNIT function or reset units to default.

3.5.6

UNIT function needs to be customized.

Screen saver option has activated.

Operation is normal. Press any key to

resume full screen power. Adjust screen

saver time, if desired. 3.5.5.1

Front panel display is dim.

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RPM4™ OPERATION AND MAINTENANCE MANUAL

SYMPTOM

PROBABLE CAUSE

SOLUTION

The Q-RPT range does not cover the desired Check that Q-RPT default range is high

AutoRange.

enough to cover the AutoRange. Table 1

The specified operating mode is absolute or

negative gauge and absolute and negative

modes are OFF for the desired Q-RPT

AutoRange is not selecting the

desired Q-RPT for the specified

range.

Check that absolute/negative gauge is ON

for the Q-RPT. 5.2.5

The Q-RPT is Gxxx (gauge only) and the

specified operating mode is absolute or

negative gauge..

Check that the Q-RPT type supports the

desired measurement mode. 3.3.3

Range will NOT change. Displays The pressure currently applied to the range

Reduce pressure applied to test port to

less than UL of target range. 3.4.4

“Pressure on Hi (or Lo) RPT

exceeds RR upper limit”.

that is being selected exceeds the UL (upper

limit) set for that range.

Pressure display is flashing and

beeper is sounding intermittently.

Current upper limit of active range has been

exceeded.

Reduce pressure. Change UL and/or

active range if needed. 3.4.4

Pressure display is flashing and

beeper is sounding intermittently

while operating in differential

mode.

Reduce differential pressure and/or

pressure on Hi Q-RPT to be less than

upper limit values or change upper limit

value(s). 3.4.4, 3.3.3.1

Differential pressure upper limit OR Hi Q-

RPT upper limit is exceeded.

Pressure display is NOT flashing

and beeper is sounding

intermittently while operating in

differential mode.

Lo Q-RPT upper limit is exceeded. If Lo Q-

RPT is displayed on second line, its

measured pressures is flashing.

Reduce pressure on Lo Q-RPT or

change its upper limit. 3.4.4, 3.3.3.1

“Hi (or Lo) RPT EXCEEDED

PMAX” displays alternating with

normal display.

Correct the overpressure condition and

cycle power ON and OFF to clear.

3.4.4.1

RPM4 Q-RPT has been overpressured

(Pmax! exceeded).

If parallel measurement mode is not

desired, change ranges or turn it off.

If parallel measurement is desired,

check that the Hi and Lo Q-RPTs are

connected to the same pressure.

RPM4 is in parallel measurement mode and

the disagreement in pressure measured by

the two Q-RPTs indicates they may not be

connected in parallel.

Rapid beeping for 8 seconds and

displayed in second line.

Ignore if having the two Q-RPTs on two

different pressures is intentional. 3.5.7.3

A Ready (green Ready/Not Ready Stability settings is too tight and/or existing

Adjust stability setting or correct other

conditions. 3.4.3, 3.2.1

indicator) indication is never

achieved.

conditions will not allow Ready to be

achieved.

Cannot select absolute or negative

gauge measurement mode.

Q-RPT is Gxxx and does not support

absolute and gauge measurement modes or

Operation is normal. 3.3.3

RPM4 must have two Q-RPTs of the same

type (Axxx, Gxxx, BGxxx) and the current

range must be the default range (<DF>) of

the Hi Q-RPT for differential measurement

mode to be available.

If RPM4 has two Q-RPTs of the same type,

set the default range of the Hi Q-RPT.

3.3.3.1

Cannot select differential

measurement mode.

Q-RPT is Axxx (absolute) but

cannot select absolute or negative mode have been turned off in the calibration

gauge measurement mode.

Absolute and negative gauge measurement

Check that absolute/negative gauge is ON

for the Q-RPT. 5.2.5

function.

Display update rate of indicated

pressure changes when changing

pressure.

RPM4 automated read rate function is ON to

automatically adjust read rate depending

upon rate of change of pressure.

Operation is normal. Turn automated

read rate function OFF if desired. 3.5.7.2

Pressure is changing but display

of pressure is NOT and the

bottom right hand corner of the

display is a numerical countdown

followed by <avg>.

Average DISPLAY function is ON and

pressure display is updating only with the

average value at the end of each averaging

cycle.

Go to a DISPLAY function other than

average or press [+/-] to get the

instantaneous value Average DISPLAY.

3.3.6

Display update of indicated

pressure is too slow when

pressure is changing quickly.

Turn automated read rate function ON to

automatically adjust read rate depending

on pressure rate of change. 3.5.7.2

RPM4 automated read rate function is OFF.

Purge and clean affected systems.

Contact DHI Authorized Service

Provider if RPM4 is contaminated

internally. Table 29

Pressure measurement seems

erratic when measuring gas

pressure.

The RPM4 and/or the connection to the test

system is contaminated with liquids.

Pressure indicated by RPM4

never becomes stable.

These is a leak in the pressure system to

which RPM4 is connected.

Find and correct leak. Consider using

RPM4 leak check function. 3.3.5

Page 132

6. TROUBLESHOOTING

SOLUTION

SYMPTOM

PROBABLE CAUSE

Compare differences observed to

tolerances on Q-RPT measurements.

1.2.2.1

Disagreement between two Q-RPTs Difference is actually within tolerance and

in system appears excessive.

acceptable disagreement.

Apparent inaccurate pressure

control/measure and little or no

response from Q-RPT:

Reference transducer destroyed by

overpressure.

Contact DHI Authorized Service Provider.

Table 29

Set desired pressure units and/or

measurement mode. Consider reference

temperature if unit is inWa. 3.3.2, 3.3.3

Incorrect pressure units and/or measurement

mode (gauge or absolute).

Apparent inaccurate pressure

measurement.

Q-RPT calibration coefficients have been

altered.

Check and correct calibration coefficients if

needed. 5.2

AutoZ has been run and turned ON with an

incorrect standard for zero.

Check value of P_offset. Rerun AutoZ with a

valid reference. 3.5.1

Apparent inaccurate pressure

measurement and <h> is

displayed on top line of screen.

An unplanned “head” correction is active or

head height or fluid is incorrect.

Operation is normal. Remove or change

“head” correction. 3.3.7

Need to run AutoZ to rezero in gauge mode.

Run AutoZ. 3.3.9

Pressure applied is zero gauge

but reading is NOT zero.

Check measurement mode setting and

set to gauge if gauge pressure

measurements are desired. 3.3.3

Current measurement mode is absolute and

RPM4 is indicating atmospheric pressure.

Operation is normal. Check

Pressure applied is atmospheric

but RPM4 indicates near zero.

Current measurement mode is gauge and

RPM4 is indicating zero gauge pressure.

measurement mode setting and set to

absolute if absolute pressure

measurements are desired. 3.3.3

A third Q-RPT designated HL is

available but RPM4 has only two

Q-RPTs.

Parallel measurement mode has been

activated.

Operation is normal. Turn off parallel

measurement mode if desired. 3.5.7.3

NOT reading pressure applied to

the test port and <SDS CLOSED>

is flashing over the pressure

indication.

SDS is CLOSED for the active Q-RPT so the

pressure applied to the test port is NOT

getting to the Q-RPT.

After taking precautions to assure that

pressure applied to test port is safe for

the RPT, OPEN SDS. 3.2.7, 3.3.8

Familiarize yourself with your RPM4

configuration. Connect pressure to be

measured to correct TEST(+) port.

2.3.5, 5.6

RPM4 may have two TEST(+) ports and the

pressure to be measured is connected to the

wrong Q-RPT’s port

Is NOT reading pressure applied

to the TEST(+) port.

RPM4 may have two TEST(+) ports and

pressure to be measured is connected to

correct port but active Q-RPT is NOT the

Q-RPT on that TEST port.

Familiarize yourself with your RPM4

configuration. Select active range to be

on the Q-RPT to which the pressure to

be measured is corrected. 5.6, 3.3.1

<SDS CLOSED> is displayed

alternating with the measured

pressure.

Operation is normal. OPEN SDS if

desired. 3.3.8

SDS is CLOSED for the active Q-RPT.

SDS should be present on a

Q-RPT but does not seem to be

active.

SDS has been turned full time OFF for the

Q-RPT.

Turn SDS full time ON. 3.5.4.2

When not in differential or parallel

measurement mode, SDS on the inactive

Q-RPT can only be OPENED using direct

SDS control.

SDS will not OPEN for the Q-RPT

shown on the second line in the

Q-RPT DISPLAY function.

Use direct SDS direct control to OPEN

SDS on the inactive Q-RPT. 3.5.4.1

SDS was left OPEN on one

Q-RPT when ranges were

changed. When you come back

to it, its CLOSED again.

When changing ranges causes a change of

the active Q-RPT, SDS is always CLOSED

for the Q-RPT that becomes inactive.

Operation is normal. 3.2.7

You would like to eliminate the

SDS function for a Q-RPT.

Set SDS to be inactive except for an

overpressure situation.

Turn SDS full time OFF for the Q-RPT.

3.5.4.2

Page 133

RPM4™ OPERATION AND MAINTENANCE MANUAL

NOTES

Page 134

7. APPENDIX

7.1

REMOTE [ENT]

The RPM4 remote ENTER function operates by detecting the open or closed status of the REMOTE

ENTER switch.

The normal status of the ENTER switch is OPEN. When RPM4 detects a CLOSED condition held for 300 ms,

it is interpreted as equivalent to a press of the [ENT] key.

Any switch may be used to accomplish the remote ENTER function. The switch should be installed on

the optional remote ENTER cable (DHI P/N 103128). Install the switch by connecting its two terminals to

the black and white wires of the remote ENTER cable.

Figure 10. Remote [ENT] Connector Schematic

1. Black wire

2. White wire

Page 135

RPM4™ OPERATION AND MAINTENANCE MANUAL

7.2

UNIT CONVERSION

7.2.1

PRESSURE

RPM4 performs all internal calculations in SI units. Numerical values input or output in other

units are converted to SI immediately after entry and back to other units just before output as

needed.

Table 28 provides the conversion coefficients used by RPM4 to convert numerical values

expressed in SI units to corresponding values expressed in other units.

Table 28. Pressure Unit of Measure Conversion Coefficients

TO CONVERT FROM Pa To

Pascal

MULTIPLY BY

1.0

mbar

millibar

1.0 E-02

hPa

hecto Pascal

1.0 E-02

kPa

kilo Pascal

1.0 E-03

bar

Bar

1.0 E-05

mmWa @ 4°C

mmHg @ 0°C

psi

millimeter of water

millimeter of mercury

pound per square inch

pound per square foot

inch of water

1.019716 E-01

7.50063 E-03

1.450377 E-04

1.007206 E-06

4.014649 E-03

4.021732 E-03

4.018429 E-03

2.953 E-04

psf

inWa @ 4°C

inWa @ 20°C

inWa @ 60°F

inHg @ 0°C

kcm²

inch of water

inch of mercury

kilogram force per centimeter square

milliTorr (micron of mercury

Torr (millimeter of mercury)

User

1.019716 E-05

7.50063

mTorr

Torr

7.50063 E-3

user

User defined coefficient

see Altitude Note below

feet of altitude

meter of altitude

Altitude Note:

Quantities expressed in units of altitude follow MIL-STD-859A

“Static Pressure, p, in Inches of Mercury for Values of Pressure Altitude, H,

in Geopotential Feet.” MIL-STD-859A provides tables of pressure in inches of mercury

as a function of altitude in feet. RPM4 uses a set of equations to model the

pressure/altitude relationship. The worst case deviation between the MIL-STD-859A

table and the calculated pressure is 0.0001 inches of mercury (0.3 Pa). The pressure

quantity expressed in inches of mercury is converted to Pascal following Table 28 above.

For altitude expressed in meters, meters are converted to feet using 1 m = 3.28084 ft.

Page 136

8. WARRANTY

8.1

OVERVIEW

Except to the extent limited or otherwise provided herein, DH Instruments warrants for one year from

purchase, each new product sold by it or one of its authorized distributors, only against defects in

workmanship and/or materials under normal service and use. Products which have been changed or

altered in any manner from their original design, or which are improperly or defectively installed, serviced

or used are not covered by this warranty.

DH Instruments and any of its Authorized Service Providers’ obligations with respect to this warranty are

limited to the repair or replacement of defective products after their inspection and verification of such

defects. All products to be considered for repair or replacement are to be returned to DH Instruments or

its Authorized Service Provider after receiving authorization from DH Instruments or its Authorized

Service Provider. The purchaser assumes all liability vis a vis third parties in respect of its acts or

omissions involving use of the products. In no event shall DH Instruments be liable to purchaser for any

unforeseeable or indirect damage, it being expressly stated that, for the purpose of this warranty, such

indirect damage includes, but is not limited to, loss of production, profits, revenue, or goodwill,

even if DH Instruments has been advised of the possibility thereof, and regardless of whether such

products are used individually or as components in other products.

The provisions of this warranty and limitation may not be modified in any respect except in writing signed

by a duly authorized officer of DH Instruments

The above warranty and the obligations and liability of DH Instruments and its Authorized Service

Providers exclude any other warranties or liabilities of any kind.

Table 29. DHI Authorized Service Providers

DH INSTRUMENTS

AUTHORIZED SERVICE PROVIDERS

TELEPHONE,

FAX & EMAIL

NORMAL SUPPORT

REGION

COMPANY

DH Instruments

ADDRESS

4765 East Beautiful Lane

Phoenix AZ 85044-5318

USA

Tel 602.431.9100

Fax 602.431.9559

[email protected]

Worldwide

Chrysantstraat 1

3812 WX Amersfoort

the NETHERLANDS

Tel (+31) 33.46.22.000

Fax (+31) 33.46.22.218

[email protected]

European Union

Japan/Asia

Minerva Meettechniek B.V.

258-1, Nakadai

Kasumigaura-machi,

Niihari-Gun,

Tel 81/29.840.9111

Fax 81/29.840.9100

[email protected]

Ohte Giken, Inc.

Technology Center

Ibaraki 300-0133

National Institute of Metrology

Heat Division

Pressure & Vacuum Lab

NO. 18, Bei San Huan Donglu

Beijing 100013

Tel 010.64291994 ext 5

Tel 010.64218637 ext 5

Fax 010.64218703

Peoples Republic of

China

DH Products Technical

Service Division

[email protected]

PR CHINA

Page 137

RPM4™ OPERATION AND MAINTENANCE MANUAL

NOTES

Page 138

9. GLOSSARY

A type of Q-RPT with a built-in vacuum reference that is intrinsically absolute (e.g. A10M).

Axxx Q-RPTs support absolute, gauge and negative gauge measurement modes.

Axxx

Absolute Mode

Active Q-RPT

Measurement mode in which the Q-RPT indicates absolute pressure (difference from vacuum).

The Q-RPT that is currently selected to be displayed on the top line of the RPM4

display. Most function selections affect the active Q-RPT.

A function that optimizes RPM4 measurement and control for a specific, user defined

range of operation.

AutoRange

AutoRanged Range

AutoTest or ATest

AutoZero or AutoZ

Barometer

An RPM4 pressure measurement range created using the AutoRange function.

RPM4 on-board automated testing sequences and their results.

A process by which a Q-RPT and measurement mode is rezeroed (offset) relative to a standard.

RPM4’s on-board atmospheric pressure measuring sensor. Also referred to as on-board barometer.

A type of Q-RPT that is intrinsically gauge and is capable of operating bi-directionally,

above and below atmosphere, through zero. BGxxx Q-RPTs support gauge and

negative gauge measurement modes.

BGxxx

Default Range (DF)

Deviation

A Q-RPT’s maximum range that is always available using [RANGE] and cannot be deleted.

A DISPLAY function in which the deviation of the current pressure from a target pressure

is displayed.

Device Under Test. The device or devices pneumatically connected to the RPM4

TEST(+) port that the RPM4 is being used to test or calibrate.

DUT

Measurement mode in which the measured pressure is the different between the Hi and

Lo Q-RPT (Hi – Lo).

Differential mode

Abbreviation of “full scale”. The full scale value is the maximum pressure of a measurement

range. Limits and specifications are often expressed as % FS. Also see span.

A type of Q-RPT that is intrinsically gauge but only measures pressure greater than

atmosphere. Gxxx Q-RPTs support gauge measurement mode only.

Gxxx

Measurement mode in which the Q-RPT indicates gauge pressure (difference from

atmospheric pressure), but only in the positive direction (above atmosphere).

Gauge Mode

Head

A difference in height between the RPM4 reference level and the DUT.

A DISPLAY function in which the highest and lowest pressure measurements since

reset are recorded and displayed.

HiLo

The designation of a single Q-RPT in an RPM4, or, if there are two, the one that has the

highest full scale default range.

Hi Q-RPT

HL Q-RPT

The designation of the pseudo Q-RPT that results from the combination of using two

Q-RPTs simultaneously in parallel measurement mode.

In an RPM4 with two Q-RPTs, the Q-RPT that is not currently displayed on the top line

of the display. The inactive Q-RPT may be displayed on the second line of the RPM4

display using the RPT DISPLAY function.

Inactive Q-RPT

The designation of a the Q-RPT with the lower full scale default range in RPM4s with

two Q-RPTs.

Lo Q-RPT

Whether pressure is being measured relative to absolute zero or vacuum (absolute mode)

or relative to atmospheric pressure (gauge mode).

Measurement Mode

Measurement mode in which the Q-RPT indicates gauge pressure (difference from

atmospheric pressure), in both positive and negative directions (above and below

atmosphere).

Negative gauge or

compound gauge

The difference between a Q-RPT reading and the AutoZero reference at the time AutoZ

is run. Used by the AutoZ function when Auto Z is ON to compensate Q-RPT readings

for changes in zero over time.

P_offset

AutoZero reference value. Value indicated by the device against which the Q-RPT is

zeroed by AutoZ.

P_std,0

Pressure adder, used to offset a Q-RPT or barometer to calibrate it.

Page 139

RPM4™ OPERATION AND MAINTENANCE MANUAL

Pressure multiplier, used to adjust span of a Q-RPT or barometer to calibrate it.

Operating mode of RPM4s with two Q-RPTs in which both Q-RPTs are used to measure

together in parallel and the indicated pressure is the average of their readings. This

creates a pseudo Q-RPT designated HL.

Parallel Measurement

Mode

The maximum pressure limit of a Q-RPT. If the pressure measured by the Q-RPT

exceeds Pmax!, an overpressure condition occurs.

Pmax!

PPC3

Pressure controller calibrator manufactured by DHI. RPM4 can be used as an external

reference device for a PPC3. PPC3 automates RPM4 pressure control.

The transducer used by RPM4 for low uncertainty pressure measurement. May be

designated as Hi, Lo or HL depending on its position and role in t he RPM4.

Q-RPT

(Quartz Reference

Pressure Transducer)

Q-RPTs are designated by a leading A, G or BG (absolute, gauge or bi-directional

gauge) followed by three numbers and a letter indicating the maximum range of the

Q-RPT in kPa (nnnK) or MPa (nnnM).

A DISPLAY function in which the rate of change of pressure in pressure unit/second is

displayed.

Rate

Front panel LED indication of when the pressure measured by RPM4’s active Q-RPT is

stable within the stability limit. Leading character of the second line when the inactive Q-

RPT is displayed on the second line in RPT DISPLAY mode.

Ready/Not Ready

RPT2x

Parallel measurement mode in which both Q-RPTs of an RPM4 with two Q-RPTs are

used together and the indicated pressure is the average of their measurements.

SDS (Self Defense

System)

A system to protect Q-RPTs from overpressure made up of isolation and vent valves

and internal operating logic. Applies only to Q-RPTs designated A7M or lower.

The difference between FS and the lowest point in a range. For example, the span of a

100 kPa FS range in negative gauge mode is nominally 200 kPa (from - 100 kPa to 100 kPa).

Span

A limit expressed in units of pressure per second (e.g., kPa/second). The stability limit is used

as the Ready/Not Ready criterion. Ready if rate of change is less than stability limit.

Not Ready if rate of change is greater than stability limit.

Stability Limit

Target

The value from which deviations are measured in the Deviation DISPLAY function.

A user settable maximum pressure limit. When pressure exceeds UL, RPM4 beeps

intermittently. In negative gauge measurement mode, there is also a user settable lower limit.

UL (Upper Limit)

User Level

QDUT

Levels of security that can be set to protect certain RPM4 functions from being accessed.

On-board automated test sequence that AutoRanges RPM4 based on characteristics of

the Device Under Test (DUT).

Page 140

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