GE
Sensing
RPT 301
Digital Output Pressure Transducer
User Manual K177
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RPT 301
Digital Output Pressure Transducer
User Manual
K177
© Druck Limited 1998
This document is the property of Druck Limited and may not, either in part or whole, be copied or
otherwise reproduced, communicated in any way to third parties, nor stored in any Data Processing
System, without the express written authority of Druck Limited.
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RPT 301 User Manual
Safety
i
ꢀ
The manufacturer has designed this instrument to be safe when operated
using the procedures detailed in this manual. Do not use this instrument for
any other purpose than that stated. Do not apply values greater than the
maximum value stated.
ꢀ
This manual contains operating and safety instructions that must be
followed for safe operation and to maintain the instrument in a safe
condition. The safety instructions are either warnings or cautions issued to
protect the user and the equipment from injury or damage. Use qualified*
technicians and good engineering practice for all procedures in this manual.
Pressure
Do not apply pressure greater the maximum safe working pressure to the
instrument.
Electrical Safety
This instrument is designed to be safe when using options and accessories
supplied by the manufacturer.
Toxic Materials
There are no known toxic materials used in this instrument.
Maintenance
The instrument must be maintained using the manufacturer’s procedures
andshouldbecarriedoutbyauthorisedserviceagentsorthemanufacturer’s
service departments.
Technical Advice
For technical advice contact the manufacturer or subsidiary refer to section
5.5.
*
A qualified technician must have the necessary technical knowledge,
documentation, special test equipment and tools to carry out the required
work on this instrument.
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ii
RPT 301 User Manual
Abbreviations and Symbols
The following abbreviations are used in this manual.
Note:
EMC
FS
Abbreviations are the same in the singular and plural.
electromagnetic compatibility
full-scale
IEC
inHg
International Electrical Council
inch of mercury
kg/cm2
kPa
mA
kilogram per centimetre squared
kilo Pascal
milli Ampere
mm
NL, H & R
PCB
psi
milli metre
non-linearity, hysteresis and repeatability
printed circuit board
pound per square inch
resonant pressure transducer
Volt
RPT
V
VA
Volt amp
The following symbols are used in this manual
Hazard, a warning highlighting a danger that would result in
injury. Also a marking on the instrument referring the user to
this publication.
This symbol, on the instrument or in the manual, indicates a
static sensitive component.
This product meets the essential protection requirements of
the relevant EEC directives. Further details of applied stand-
ards may be found in the product specification.
CE
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RPT 301 User Manual
iii
Table of Contents
1
Introduction ................................... 1
Description ................................................ 1
Specification.............................................. 1
1.1
1.2
2
Installation ..................................... 4
Mounting the Transducer ......................... 4
Pressure Connection ................................ 4
Electrical Connection ................................ 6
2.1
2.2
2.3
3
Operation ....................................... 11
System Operation ..................................... 11
Command Summary ................................. 11
General Command Format ....................... 13
General Reply Format ............................... 15
Error Message .......................................... 15
Detailed Command Definitions ................ 17
3.1
3.2
3.3
3.4
3.5
3.6
4
Calibration ..................................... 23
5
Maintenance .................................. 26
General ...................................................... 26
LED Indicator ............................................ 26
Diagnostic Mode....................................... 26
Cleaning .................................................... 27
Approved Service Agents ......................... 28
5.1
5.2
5.3
5.4
5.5
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RPT 301 User Manual
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RPT 301 User Manual
Introduction
1
1
1.1 Description
TheRPT301DigitalOutputPressureTransducermeasuresairpressure
applied to the connection port and produces an electrical output. It
comprises a resonant sensor connected to a printed circuit board to
produce a serial digital output and is contained in a metal enclosure to
IP65 standard. The instrument is designed to communicate with
compatible equipment using a serial communications system which
can be selected by the user for either RS232 or RS485 standard
communications interface. The power supply for the instrument is a
wide tolerance DC voltage with a low power consumption A remote
start-up facility enables the instrument to be remotely switched on and
off to save power.
1.2 Specification
Accuracy
Non-linearity, hysteresis and repeatability:
Standard.................................................................± 0.02% FS
Option A.................................................................. ±0.01% FS
Temperature affects:............... ±0.02% FS over operating temperature range
Long term stability:
Standard............................................. 150 ppm per 12 months
Option A............................................. 100 ppm per 12 months
Ranges
.................................................................. 750 to 1150 mbar a
.................................................................... 35 to 1300 mbar a
.................................................................... 35 to 2620 mbar a
.................................................................... 35 to 3500 mbar a
Dimensions
Weight:
...................................................................................... 0.65 kg
...................................................... 125 mm x 80 mm x 57 mm
Size:
Environment
Operating temperature range ..................................................... -20 to + 60ꢀ C
Storage temperature range ......................................................... -40 to + 80ꢀ C
Sealing:
........................................................................................... IP65
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RPT 301 User Manual
Power supply
Electrical Safety: .......................................... EN61010 (IEC 1010) as applicable
Voltage .............................................................. 4.5 to 32 V DC
Power .......................... 0.6 Watts at 5 V to 0.75 Watts at 32 V
Electromagnetic compatibility
............................................................ EN50081-1 (emissions)
............................................................. EN50082-2 (immunity)
Switch on
Settling Time: ... Less than 5 seconds (with filtering disabled)
Pressure measurement
Measurement cycle: ........................................ Fixed, nominally 0.5 seconds
Reading Filter:
Single pole low pass filter, variable time constant and step response
Reading Resolution: ........................ Programmable number of decimal places
Data Communications:
Serial RS232 or RS485 (selectable)
Software or hardware handshaking on RS232
software handshaking only on RS485.
Power Control
(Remote Start-Up)
A floating ‘volt free’ two-wire control input is provided
to enable the instrument to be remotely switched on
or off.
Pressure connection
.............................................................................. G1/8 female
overpressure ................................... 1.25 x calibrated full-scale
pressure containment ................................................... 5 bar a
Pressure medium compatibility: .......................
Dry gases compatible with:
Glass, Silicon, Titanium, Stainless Steel and Epoxy adhesive
Note: Continuing development sometimes necessitates specification changes
without notice.
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RPT 301 User Manual
3
Accessories
Thefollowingitemsaredeliveredwiththeinstrumentaftermanufacture.
ꢀ
ꢀ
ꢀ
User manual K177 (this publication)
Calibration certificate
Mating electrical connector (if ordered)
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RPT 301 User Manual
2
Installation
Installation must be carried out by a qualified technician.
2.1 Mounting the Instrument (Figure 2.1)
The instrument can be mounted on a vertical surface using two screws
or bolts to a maximum diameter of 4 mm.
Figure 2-1 Mounting Arrangement
2.2 Pressure Connection
The pressure port is a G1/8. If a pipe is connected to this port a bonded
seal must be used. The instrument is very sensitive to air movement
(small local pressure changes), when the pressure port is directly
sensing the atmosphere, the fitting of a filter or restrictor is
recommended.
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RPT 301 User Manual
5
Figure 2-2 Instrument Dimensions
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RPT 301 User Manual
2.3 Electrical Connection
The electrical connector is a 10-way connector (MIL C26482) for serial,
parallel and power connections.
Instrument Connector -
Cable Connector
Plug, Amphenol 62GB 12E12 - 10P
Socket, Amphenol 62GB 16F12 - 10S
-
Communication connections
When configured for:
RS485
RS232
A
B
C
D
E
F
=
=
=
=
=
=
=
=
=
=
Power Supply -ve
Power Supply +ve
Chassis
A
B
C
D
E
F
=
=
=
=
=
=
=
=
=
=
Power Supply -ve
Power Supply +ve
Chassis
Data out +ve
Data out -ve
Data In +ve
RTS Input
Data Out
CTS Output
Data In
G
H
J
Data In -ve
G
H
J
Data Ground
Start-Up -ve
Start-Up +ve
Data Ground
Start-Up -ve
Start-Up +ve
K
K
Power supply
Theinstrumentisinternallyfusedwithreversepolarityandovervoltageprotection.
Note: The power input is transformer isolated from the logic circuits and the
serial data link. The isolation voltage is 50V dc.
For continuous operation the ‘Start-up’ connections should be connected to the
supply, make sure the polarity is correct and the current requirements are met.
When RS232 is used, the RTS line can be connected to the `Start-up' input and
the RTS input on pin D so that the control computer can turn on the instrument.
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RPT 301 User Manual
7
The start-up +ve and -ve connections must be connected for the
instrument to operate. There are many ways of connecting the
start-up facility for example:
Power control
The current consumed by the instrument is approximately 1 mA at 3 V, 2 mA at
5 V rising to 16 mA at 32 V. If necessary, when using a supply greater than 5
V, a series resistor can be used to reduce the current drain to 1 mA.
Connections for remote on/off control
current limiting resistor
for high supply voltages
see text
Connections for continuous operation
7
4
Connections for remote on/off control using RS232 output
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RPT 301 User Manual
Communications
The installed instrument is controlled by the serial data interface.
Software or hardware handshaking can be used on the RS232 interface
and only software handshaking on the RS485 interface.
Changing the communication interface standard (Figure 2-3)
ꢀ
The communication interface standard is set at manufacture to RS232
but can be changed as follows:
ꢀ
Remove the lid of the instrument to gain access to the PCB.
CAUTION:
THE PCB CONTAINS SENSITIVE ELECTRONIC COMPONENTS.
ꢀ
Carefully connect the interface connector lead and the link LK2 in the
following positions:
RS232
interface lead to PL1
LK2 to position A
RS485
interface lead to PL3
LK2 to position B
ꢀ
Refit and secure the lid of the instrument.
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9
LK1 LK2
B
B
A
B
PL3
PL1
Figure 2-3 Changing the communication interface
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RPT 301 User Manual
Screening
Make sure that the chassis connection between the control computer
and the instrument is continuous. Use screened cable and bond the
cable screening to the connector shell of the instrument and to the
computer enclosure.
computer
screened cable
RPT
301
enclosure
connect screen
to connector shell
Screening to ensure EMC performance
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Operation
11
3
3.1 System Operation
The frequency output from the sensor is counted for a fixed number of
cycles. A mid-scale pressure gives a measurement period of
approximately 0.5 seconds. During this time a high frequency clock is
also being counted and at the end of the measuring cycle it is this value
which is transferred to the processor for conversion into its pressure
equivalent.
Measurement cycles are continuous, unless specifically interrupted
(see the G command). Each cycle delivers a new pressure value to the
programmable filter. The output of this filter is stored in a buffer and
may be requested by the control computer or sent automatically at a
programmable interval to the control computer.
3.2 Command Summary
The instrument has a range of commands summarised in the table and
detailed in this section. Some of these commands generate a reply
from the instrument, the general format of these replies is given in
section 3.4.
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RPT 301 User Manual
Command Summary Table
Command
Function
Measurement
Return stored reading
Return stored reading
R
<CR>
*
Get New Reading
G
A
X
Auto send reading
Auto send from power-up
Set-up
Set units
U
F
B
O
S
I
Set filter
Set reading resolution
Set communication parameters
Status
Identity
User calibration
User calibration (linearity)
C
P
Change protection PIN
Command Terminators
CR CRLF
* Short form of the 'R<CR>' command
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13
3.3 General Command Format
The instrument is controlled by a sequence of single letter commands.
Some commands require one or more numeric values to follow the
letter, the correct number of parameters must be sent with this type of
command. All command fields must be separated by a comma. The
instrument accepts upper-case or lower-case letters.
Single commands
Single commands should be of the form:
Command, P1, P2, ,Pn<CT>
Where, Command is a single ASCII character, P1 to Pn are numbers in
the form:
(-) mmm.ddd
or
(-)m.ddddE(-)xx
e.g.
123.456 or 1.23456E02
Example:
Single Command
<CT> is the command terminator (CR or CRLF)
A,3<CR> selects auto-send mode with 3 second period
a,3<CRLF> has the same effect
Command Strings
Commands can be strung together with a separating semicolon. The
whole command string is only interpreted and actioned when a valid
terminator is received.
Example:
Multiple Commands (Command String)
1.
O, PIN, address, baud, data bits, stop bits, parity, handshake; U, units;
P, PIN, New PIN
Reply: None
This command string sets: port address (00), baud rate, units and new PIN
.
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RPT 301 User Manual
2.
U, O; G; R; G; R; U, 16; G; R; G; R; G; R; A, 100
Reply: Reading 1 mbar
Reading 2 mbar
Reading 3 psi
Reading 4 psi
Reading 5 psi
Then at 100 second intervals - Reading psi
This command string sets the instrument units to mbar, returns two
consecutive readings, changes units to psi, returns three consecutive
readingsandthenselectsauto-sendmodewithaperiodof100seconds
between readings.
Command String Limitations
Auto-send mode and diagnostics mode are cancelled when a further
command is received, this should be used at the end of a command
string.
Note:
The C, L and T commands are interactive and are not
suitable for multiple commands.
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3.4 General Reply Format
For commands that have a reply string, the reply terminator <RT> is
always transmitted and is always <CR> followed by <LF>.
<RT> is expected with all commands but only shown in some of the
following sections for clarity (e.g.: Section 5.3 Diagnostics Mode).
Command Terminator
Command strings must end with the command terminator <CT>.
For Dumb Terminal applications press the carriage return (or enter)
key.
With a Terminal Emulator communications application, the
applicationmustbeset-uptogivetherequiredoutputwhenthecarriage
return (or enter) key is pressed.
For Custom applications, <CR> (decimal 13) or <CRLF> (decimal 13
followed by decimal 10) must be added to the end of each complete
command string.
<CT> is expected with all commands except for some interactive
commandswherefurtherexplanationisnecessary(e.g.:Section4User
Calibration).
3.5 Error Message
Error messages are generated from two sources:
a.
b.
The command decoder. A command error causes the return
of an error message and stops the rest of the command string.
The instrument sends an error message corresponding to the
command error.
A pressure sensor fault causes an error message to be sent.
Serious faults block the transmission of pressure data and
sends the error message in place of data.
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RPT 301 User Manual
Error Message Format
The form of the error message:
ERROR nn - where nn is a decimal number
Defined error numbers are:
01
02
04
08
16
32
64
-
-
-
-
-
-
-
Bad command
Bad password
Bad data detected by checksum
Data out of range
Hardware fault
Pressure outside range
System not ready
Error messages are sent when an error is detected.
Example
When first detected the hardware fault error is sent once even though
the fault persists, sending the S (status) command provides further
details of the fault.
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3.6 Detailed Command Definitions
Measurement Commands
R - Return stored reading
Thiscommandretrievesthecurrentstoredreading, asthereadingisthe
stored and filtered (if the filter is selected) there will be no delay in the
reply.
Command:
R
Reply: nnnnnnn<SP>UNITS
Where:
‘nnnnnnn’ is the stored reading as a floating point
number ‘Units’ are the units for nnnnnnn (i.e. mbar,
mH2O, psi etc.)
G - Get reading
This command initiates a new measuring cycle. The reading is not
returned by this command, string ‘G’ and ‘R’ together to return the
reading(i.e. G;R<CR>). Theinstrumentproceedstothenextcommand
after the end of the measurement cycle (see specification for duration)
or in the event of a reading failure (fault condition) after a time-out of
approximately2seconds. Thecommandsynchronisesthemeasurement
cycle with an external event.
Note:
Use of the G command overrides any filter that has been
selected. The reading obtained is passed without filtering
to the reading store.
Command:
G
Reply: None
Result: Initiates new measurement cycle
A - Auto send reading
This command places the instrument into a mode where the value
currently held in the reading store is sent to the control computer with
aspecifiedintervalbetweeneachtransmission. Autosendisterminated
by any following command.
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RPT 301 User Manual
Command:
A,nnnnnn
Where: ‘nnnnnn’ is a number between 1 and 999999. This is
the period in seconds between successive
transmissions.
Reply: None
Result: A reading is transmitted every nnnnnn seconds.
The transmission format is the same as the reply of the
‘R’ command.
X - Auto Send from switch-on
The ‘A’ command is cancelled by any following commands and is not
restored at switch-on. If the pressure transducer continuously sends
readings and does so even after power failure, (this includes using the
‘shutdown’ facility) then the ‘X’ command can be used to select this
facility. This command allows a transmission period to be stored in
nonvolatile memory which will be automatically loaded and actioned as
if the ‘A’ command had been sent at switch-on.
Command:
X,nnnnnn
Where: ‘nnnnnn’ is a number between 0 and 999999.
This is the transmission interval in seconds as for the
‘A’ command. A value of 0 disables the Auto send at
switch-on.
Reply: None
Result: Instrument powers up in auto-send mode with the
selected transmission interval.
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RPT 301 User Manual
Set-up Commands
U - Unit Set-up
19
This command sets the units of the pressure measurement; the
selection is nonvolatile.
Command:
U,nn
Where: ‘nn’ can be up to two digit number taking one of the
following values:
*
0
-
-
-
-
-
-
-
-
-
-
-
-
mbar
Pa
13
14
-
-
-
-
-
-
-
-
-
-
-
-
mH20
torr
1
2
kPa
15
atm
3
MPa
16
psi
lb/ft2
4
hPa
17
5
bar
18
inHg
6
kg/cm2
kg/m2
mmHg
cmHg
mHg
mmH2O
19
inH2O04
ftH2O04
mbar
7
20
8
*21
22
9
inH2O20
ftH2O20
mbar
10
11
23
*24
12
-
cmH2O
* Note:
mbar can be selected using code 0, 21 or 24.
Reply: None
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RPT 301 User Manual
F - Filter Set-up
This command sets the instrument reading filter coefficients.
Command:
Where:
F, step, average
stepisapressurebandwithinwhichthefilteroperates.
If the pressure steps outside this band, the filter is
bypassed. This gives an unfiltered response to
non-noise step changes.
step takes a value expressed as a percentage (0 -
100%) of full-scale.
If step = 0 then the filter is disabled.
average is the number of sequential readings (1 -
99) averaged by the filter. High values effectively
give the filter a long time-constant.
Reply: None
B - Set Resolution
This command enables the decimal place of the reading to be adjusted
within the instrument’s resolution, see specification. The reading
resolution is automatically selected according to the instrument full-
scale and the units that have been selected using the units set-up
command. An algorithm is used that gives a resolution which does not
interfere with the accuracy of measurement and is as noise-free as
possible before filtering. The set resolution command allows the
number of decimal places of the transmitted value to be specified, this
overrides the automatic selection of resolution for the current selected
units.
Changing units cancels any previous set resolution command.
The command is nonvolatile and remains selected until the units are
changed. Changing and restoring the units can be used to cancel the
set resolution command.
Command:
B,n
Reply: None
Result: Sets the transmitted number of decimal places to be ‘n’ 0-5
max depends on units resolution.
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21
O - Set Communications Options
Thiscommandsetsthecommunicationportparameterstomatchthose
of the control computer.
Note: When changing these settings care must be taken to avoid losing
communication with the instrument. If this should happen the default
communications settings can be restored (those operational at the time
of shipment) by moving Link 1 to the ‘A’ (Restore) position and
switching the power off and back on. The link should then be moved
back to the ‘B’ (Normal) position. If the link is left in the ‘A’ (Restore)
position it is not possible to permanently change the communications
settings; this may be considered useful in some applications. Default
on shipment is set to the command O, 000,00,0,0,0,0,0 which means:
9600 baud, 8 data bits, 2 stop bits, no parity, no handshake.
Command:
O, PIN, address, baud, data bits, stop bits,
parity, handshake
Where: PIN is a three-character password = 000 - 999
address always = 00
baud rate value = 0 - 7: 0 = 9600, 1 = 4800, 2 = 2400, 3 = 1200,
4 = 600, 5 = 300, 6 = 150, 7 = 75
data bits:
stop bits:
parity:
0 for 8 data bits1 for 7 data bits
0 for 2 stop bits
1 for 1 stop bit
0 = no parity 1 = even parity 2 = odd parity
0 = no handshake
handshake:
1 = software handshake (XON/XOFF)
2 = hardware handshake (RTS/CTS)
Reply: None
Note: When RS485 hardware has been selected the serial link is configured as
full duplex with no hardware handshaking. Handshake = 2 is not valid
for RS485 hardware.
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RPT 301 User Manual
S - Status
This command returns the instrument status.
Command:
S
Reply:
STATUS nn
Where nn:
01 = Frequency outside limits
02 = Diode voltage outside limits
04 = Electronics failure
Combination errors: a status 06 represents diode
voltage and electronics failure.
Result:
no change
I - Identity
This command requests the unit to send items of data which describe
the unit identity.
Command:
Reply:
I
type, range, S/N, cal date
Result:
No change in status or operation
Where:
Type =
Range =
Equipment model (Druck RPT 301)
Pressure range, lower and upper and
pressure type
S/N
Cal date =
=
Transducer serial number
Date of last calibration
Command:
I,S/PIN, Name Value<CR> format
i.
When Name = S, Value = nnnn/yy-mm
Reply: S/N = nnn/yy-mm
Result: sets displayed serial number
ii.
iii.
When Name = H, Value = nnnn
Reply: HIGH RANGE = nnn mbar
Result: sets displayed highest operating pressure (mbar)
When Name = L, Value = nnnn
Reply: LOWEST RANGE = nnn mbar
Result: sets displayed lowest operating pressure (mbar)
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4 Calibration
23
The instrument is supplied with a calibration certificate. For the
instrument to stay accurate it is recommended that it is checked every
12 months.
ꢀ
ꢀ
ꢀ
The use of a Class A compensated deadweight pressure standard is
recommended.
The following procedures should be carried out in a controlled
environment by qualified personnel.ꢁ
Iftheaccuracyoftheinstrumentisnotwithinthespecification, carryout
a calibration adjustment procedure.
ꢁ
A qualified person must have attended a product training
course given by the manufacturer or appointed agent and
successfully completed the training course on this equipment.
ꢂ
The manufacturer offers a comprehensive and, if required,
NAMAS accredited calibration service.
ꢃ
Calibration Check
A calibration check should be carried out at chosen intervals. The
readingsoftheinstrumentshouldbecomparedwithapressurestandard
and, after any adjustments for accuracy (traced to National Standards),
the differences recorded. The adjusted differences can then be
compared with the required accuracy for the instrument. If necessary
a calibration adjustment can be carried out.
The recommended procedure is to check at increasing and then
decreasing intervals of 0, 20, 40, 60, 80 and 100% of full-scale.
C - User Calibration (Linearity/Drift Compensation)
This command performs a `best straight line fit' to the remaining errors
of the transducer or does a single pressure point correction. Entering
one pressure point causes the offset between the transducer and the
pressure standard to be added/subtracted across the whole pressure
range. Entering two pressure points (near zero and near full-scale)
cancelszeroandfull-scaledrift. Enteringmorepressurepointsreduces
the remaining non-linearity and makes the zero and full-scale correction
more accurate.
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RPT 301 User Manual
The calibration routine requires a minimum of two pressures within the
operating extremes (maximum of six pressures). The instrument
software calculates an offset and gain correction to be applied to all
subsequent readings using a statistical best straight line method.
For single point calibration, the gain factor is set to unity.
Notes
1
For the pressure sensor to rapidly respond to the applied pressure,
disable the filter by sending the filter command F, 0,0<CR>.
2
Before sending the ‘C’ command set the instrument to operate in the
pressure measurement units required for calibration. i.e. U, 0<CR>
selects mbar. Always use the same units when entering applied
pressures.
Command:
Reply:
C, PIN
APPLY PRESSURE nn
apply pressure, when steady send <CT>
ENTER APPLIED PRESSURE nn
type pressure value - decimal number followed by
Reply:
<CT>
Reply:
MORE? (Y/N)
type Y <CT> to calibrate more points
or
or
type N <CT> to complete calibration point entry
SLOPE XX INTERSECT YY
ACCEPT CALIBRATION (Y/N)
Reply (if N):
type Y <CT>
to accept and permanently update the calibration
type N <CT> to terminate without saving
Reply (if N): CALIBRATION TERMINATED
end of calibration procedure
Reply (if Y):
ENTER CAL DATE
type date in the format DD/MM/YY
CALIBRATION COMPLETE
Where:nn = pressure point 1-6
Reply:
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RPT 301 User Manual
25
P - Change PIN
This command changes the PIN (Personal Identification Number) that
protects the calibration data. The instrument is shipped with the PIN
000. If the PIN is lost, the default (000) may be restored by fitting the
‘default’ link and switching off and then on.
Note: Restoring the defaults restores ALL of the factory settings including the
communication parameters.
Command:
Where:
P, PIN, New PIN
PIN is the existing 3-digit code (000 to 999) and New
PIN is the replacement PIN.
Reply:
None
Result:
PIN is replaced by New PIN
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RPT 301 User Manual
5
Maintenance
5.1 General
User maintenance on this instrument is limited to checking the LED
indicator, a diagnostic mode and cleaning the case.
5.2 LED Indicator
With the lid of the instrument removed, an LED located on the PCB
flashes when a pressure conversion is carried out. This indicates that
the instrument has power, that the processor is functioning and the
transducer frequency and diode voltage are within normal limits.
5.3 Diagnostic Mode
D - Diagnostic Mode
This command places the instrument into the diagnostic mode.
Command:
Where:
D, mode
mode is a single digit:
1
2
3
4
5
Dump all 512 stored values.
Dump transducer coefficients (checks LOAD L command).
Dump calibration factors i.e. gain, offset etc.
Continuous output of sensor diode voltage (temperature) mV.
Continuous output of sensor frequency in Hz.
Result: The reply depends on the mode as follows:
Mode 1
32 lines of output as follows:
aaa - nn nn nn nn nn nn nn nn nn nn nn nn nn nn nn nn<RT>
where: aaa = hexadecimal address offset (0 to 1FFH) and
nn = hexadecimal data
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RPT 301 User Manual
27
Mode 2
“K00”,Coeff 1<RT>...”K55",Coeff 25<RT>,
”KX”,Coeff X<RT>,
”KY”,Coeff Y<RT>,
“CS”,RPT barometric checksum<RT>,
“SN”,RPT serial number<RT>,
“RH”,RPT max. operating pressure (mbar)<RT>,
“LH”,RPT min. operating pressure (mbar)<RT>,
“TYPE”,RPT type<RT>
Mode 3
Frequency constant, pressure gain, pressure offset, diode volts offset
Mode 4
DIODE = value - For every reading where value is the diode voltage in
mV
Mode 5
FREQUENCY = value - For every reading
Where: ‘value’ is the sensor frequency measured in Hz
*
Modes 4 and 5 are cancelled by any other command.
5.4 Cleaning
Cleantheexternalcaseoftheinstrumentwithadamplint-freeclothand
mild detergent. Make sure that there is no debris in the pressure port.
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RPT 301 User Manual
5.5
Approved Service Agents
Find approved agents for the servicing of Druck Instruments at:
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