Teledyne Satellite Radio LXT 230 User Manual

Model LXT-230 Transmitter  
Installation and Operating Manual  
for  
pH and ORP  
Teledyne Analytical Instruments  
16830 Chestnut Street • City of Industry, CA 91748  
Download from Www.Somanuals.com. All Manuals Search And Download.  
6.6 Calibration Error Detection & Electrode Operational Guidelines.............................. 15  
6.7 Back-to-Factory Calibration .............................................................................. 15  
6.8 Output Calibration........................................................................................... 15  
6.9 Temperature Calibration - Trim Adjustment........................................................ 16  
6.10 Temperature Units Calibration - Celsius/Fahrenheit Conversion........................... 16  
7.0 LXT-230 MODEL NUMBER DESIGNATORS.............................................................. 18  
8.0 TROUBLESHOOTING GUIDE................................................................................. 19  
APPENDIX A - SPECIFICATIONS................................................................................. 21  
Model LXT-230 Instruction Manual / 3  
Download from Www.Somanuals.com. All Manuals Search And Download.  
UNPACKING THE INSTRUMENT  
Your Teledyne instrument has been carefully packaged to protect it from damage during  
shipment and dry storage. Upon receipt please follow the procedure outlined below.  
1. Before unpacking, inspect the condition of the shipping container to verify proper  
handling by the carrier. If damage is noted, save the shipping container as proof of  
mishandling for the carrier.  
2. Check the contents of the shipping container with the items and quantities shown on the  
packing list. Immediately report any discrepancies to TAI.  
3. Save the original packing material until you are satisfied with the contents. In the event  
the transmitter must be returned to TAI, the packing material will allow you to properly ship  
it to TAI.  
4. Familiarize yourself with the instrument before installation, and follow proper installation  
and wiring procedures.  
1.0 GENERAL DESCRIPTION  
Teledyne's Model LXT-230 is a microprocessor-based two-wire transmitter for process  
control of pH, ORP and Specific Ion. Incorporating microprocessor technology, the LXT-230  
provides the following features:  
1.1 Membrane Switches  
Calibrations can be performed via membrane switches located on the front cover, removing  
the need to open the NEMA 4X enclosure and exposing components to the environment. No  
potentiometric adjustments are required.  
1.2 Digital Display  
A 32-character Supertwist alphanumeric liquid crystal display (LCD) is used to display data  
menus. The two rows of 16 characters can be adjusted to different contrast intensities for  
easy viewing.  
1.3 Automatic Buffer Calibration  
Allows buffer points to be defined upon initialization of the transmitter so that no  
adjustments are required for future buffer calibrations.  
1.4 Back To Factory Calibration  
Allows the transmitter to be returned to a predetermined factory calibration. The default  
parameters are zero electrode offset at 7.00pH or 0.00mV ORP and the ideal Nernstian  
slope for the appropriate measurement.  
1.5 Current Output  
A standard LXT-230 transmitter is provided with a 4-20 mA current output transmitted on  
the same 24-vdc power wiring. The current output may be expanded to any range within  
the transmitter's full operating range (see specifications). For customer controllers that are  
not capable of reverse acting control, the LXT-230 allows the current output to be reversed;  
for example, a 4-20 mA output for a range of 0-14 pH can be reversed to 14-0 pH.  
1.6 Temperature Conversion  
This standard feature allows the temperature displays to be presented in Celsius or  
Model LXT-230 Instruction Manual / 4  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Fahrenheit. A toggle function in the Temperature Calibration Menu allows this selection to  
be performed in the field.  
1.7 PID Output (Optional)  
An optional PID output is available and provides a 4-20 mA, three-mode control signal to a  
transducer or a final control element. Proportional band is adjustable from 0.1 to 1,000%.  
Reset and Rate are adjustable from 0.00 to 100 repeats per minute and 0.00 to 1,000  
minutes, respectively.  
1.8 Dual Input (Optional)  
An optional second input can be provided for pH, ORP, Dissolved Oxygen or Specific Ion.  
This input can be used as a second analysis or as specific compensation for the primary  
input. Temperature compensation for the secondary input (channel 2) is provided through  
the primary input (channel 1).  
1.9 Dual Output (Optional)  
The standard LXT-230 is provided with a single output; however, the dual output option  
provides a second output in either a 4-20 mA regenerated or a 4-20 mA PID format.  
Outputs can be defined in pH, ORP, Specific Ion, Dissolved Oxygen or Temperature. The  
second output is fully isolated from the inputs and the primary output and is "floating" so it  
can have either a positive or negative common.  
1.10 Three Outputs (Optional)  
Because temperature is an input on the primary channel, TAI has made it available as a  
third 4-20 mA output. The third output for the LXT-230 can only be a temperature output.  
1.11 Optional Software  
To enhance the capability of the LXT-230, other software options are available.  
Among the options are:  
1.11.1 Security Access  
Allows only authorized personnel entry to calibration modes.  
1.11.2 Differential Output  
Provides an output expressed as the difference between two inputs.  
1.11.3 Ratio Output  
Provides an output expressed as the ratio of two inputs. This is applicable to percent  
rejection in some applications.  
1.11.4 Averaged Outputs  
1. Provides an output expressed as the average of two inputs.  
2. Provides a field selectable time average (2 to 32 seconds).  
1.12 Identification  
The full model number, as found on the packing slip, is a list of alphanumeric characters  
used to designate certain features of the transmitter. See section 10.0 (Table 1) for the list  
of designators used for the LXT-230.  
Model LXT-230 Instruction Manual / 5  
Download from Www.Somanuals.com. All Manuals Search And Download.  
2.0 INSTALLATION  
2.1 Mounting  
Three typical installation configurations are available for the LXT-230 transmitter: universal  
mounting, handrail mounting, and panel mounting configurations. The universal mounting  
configuration allows the LXT-230 to be mounted on a wall or a 2” pipe stand. U-bolts may  
be ordered separately for pipe stand mounting.  
2.2 Power Wiring  
The LXT-230 transmitter requires a nominal 24-vdc voltage source. With zero loop  
impedance, the minimum voltage requirement is 13.5 vdc. The maximum voltage limit is 50  
vdc. Maximum loop impedance at 24 vdc is 525 ohms for the 4-20 mA compliance.  
Impedance levels higher than 525 ohms will require additional dc voltage.  
When connecting the power wires, it is important to observe the polarity. Although no  
damage to the LXT-230 will result from polarity reversal, the LXT-230 will not function.  
CAUTION  
Do NOT apply 110 vac to the 24-vdc wiring terminals. Damage to the instrument  
will result!  
Multiple channel transmitters can have each channel powered by separate power supplies,  
or they can be powered by one power supply.  
2.3 Sensor Wiring  
A conditioned input is required from the sensor or electrode to the LXT-230 transmitter for  
proper operation. In cases where S10 and S17 sensors are not used, a signal conditioning  
module is available and can be mounted inside the LXT-230 enclosure.  
If preferred, the signal conditioner can be mounted remotely within a separate NEMA 4X  
enclosure. When used without an S10 or S17 sensor, signal conditioners for the LXT-230 do  
not provide temperature compensation. In these cases, a separate temperature sensing  
element is required for input to the temperature compensation circuitry.  
Model LXT-230 Instruction Manual / 6  
Download from Www.Somanuals.com. All Manuals Search And Download.  
3.0 FAMILIARIZATION  
This section will provide an overview of the front panel key functions and the display menus  
for a single channel pH and ORP transmitter. Multiple channel transmitters will have the  
same menus.  
3.1 Key Functions  
Cursor positions or numeric adjustments are performed by pressing the appropriate keypad.  
The LXT-230 uses an "underline" cursor in each of the menus. Holding down the keypad will  
automatically scroll the cursor or numeric values. Please note that simultaneous pressure on  
both vertical keys or any combination of keys other than the two horizontal CALIBRATE keys  
is not recommended.  
3.1.1 Menu Selection Keys  
The MENU SELECTION keys are used to change the display menu and move the cursor  
vertically. Any menu can be accessed by the use of the appropriate up or down MENU  
SELECTION key, advancing the screen to the desired menu. These keys are also used to  
exit the calibration mode and save calibration data.  
3.1.2 Calibrate Keys  
The horizontal CALIBRATE keys are used to enter the calibrate mode and move the cursor  
horizontally. To enter the calibrate mode, both horizontal CALIBRATE keys must be pressed  
simultaneously. Once in the calibrate mode, the cursor can be positioned by pressing the  
individual right-hand or left-hand CALIBRATE keys.  
The vertical CALIBRATE keys are used to perform numeric adjustments to displayed values.  
To use these keys, the LXT-230 must be in the calibrate mode. Pressing the upper  
CALIBRATE key will increase the value; pressing the lower CALIBRATE key will decrease the  
value.  
To exit the calibrate mode, press either of the MENU SELECTION keys.  
3.2 Display Menus and Screens  
When the LXT-230 is first powered, the Copyright Display will appear for a few seconds,  
then the LXT-230 will display the Main Menu.  
S/N 1234  
(C) ECD  
V 2.01  
2002  
The Copyright Display provides the software "version" number and the software serial  
number. TAI will require this information if software updates are to be performed. To access  
any of the menus listed below, press the desired MENU SELECTION key.  
3.2.1 Contrast Menu  
Display contrast can be adjusted to allow for variations of ambient lighting. The Contrast  
Menu is the same for all LXT-230 transmitters and is the uppermost screen. To access this  
menu from the Main Menu, press the upper MENU SELECTION key.  
Contrast  
20  
Model LXT-230 Instruction Manual / 7  
Download from Www.Somanuals.com. All Manuals Search And Download.  
3.2.2 Main Menu  
This menu appears after the Copyright Display when power is first applied to the LXT-230.  
The Main Menu displays the measured process variable, temperature, and the current  
output in percent of full-scale. While in this menu, the current output can be adjusted and  
locked in a manual mode to provide an undisturbed output during buffer calibrations.  
pH  
_50.0%  
7.00  
25.0°C  
ORP  
_25.0%  
-500.0 mV  
25.0°C  
3.2.3 Electrode Diagnostic Screen  
As an informational screen only, this display provides diagnostic data pertaining to the  
electrode. The top line displays the real-time (active) absolute millivolt value (mVa) the  
electrode is generating, not compensated for temperature variations. The bottom line  
displays the electrode isopotential from the last calibration. The isopotential (electrode  
offset) is the value at which the electrode output is zero millivolts. A perfect pH electrode  
will indicate an isopotential of 7.00 pH. Replace the electrode if the isopotential is less than  
6.00 pH or greater than 8.00 pH.  
Input  
0 mVa  
.0 mVa  
7.00  
Input  
0 mVa  
-500.0 mVa  
.0 mVa  
A perfect ORP electrode will indicate an isopotential of 86 mV @ 25°C. Replace the electrode  
if the isopotential is less than 36 mV or greater than 136 mV @ 25°C.  
This information is extremely helpful in determining the diagnostic status of a pH or ORP  
electrode. In conjunction with regular calibrations, the Electrode Diagnostic Screen provides  
valuable information to track electrode performance.  
3.2.4 Electrode Standardization Menu  
Provides the means with which to perform a one-point calibration (standardization) or the  
first point of a two-point calibration. For pH this point is typically 7.00 pH and ORP this point  
is typically 0.00 mV.  
1 ORP  
Cal  
.0 mV  
.0 mVa  
1 pH  
Cal  
7.00  
.0 mV/pH  
Before entering the calibrate mode, the menu provides historical data from the last  
calibration. The top line displays the buffer, or calibration point, at which the last calibration  
was performed. The bottom line displays the temperature compensated mV value the  
electrode generated at the buffer point. Please note that temperature compensation is not  
performed for ORP. When in the calibrate mode, the bottom line displays the real-time, or  
active, millivolt value.  
3.2.5 Electrode Span Menu  
Provides the means to perform the span calibration, or the second point of a two-point  
calibration. Before entering the calibrate mode, the menu provides historical data from the  
last calibration.  
2 ORP  
Cal  
.0 mV  
1.000 mV / ORP  
2 pH  
Cal  
.00  
-59.1 mV/pH  
Model LXT-230 Instruction Manual / 8  
Download from Www.Somanuals.com. All Manuals Search And Download.  
The top line displays the buffer, or calibration point, at which the last calibration was  
performed. For pH transmitters, the bottom line displays the electrode slope, or efficiency,  
in millivolts per pH (mV/pH). ORP transmitters express efficiency in absolute millivolts per  
millivolt (mVa/mV). When in the calibrate mode, the bottom line displays the real-time, or  
active, millivolt slope value.  
3.2.6 Output Calibration Menu  
Current output ranges are adjusted in this menu. The top line defines the 4 mA point, while  
the bottom line defines the 20 mA point. Between these points, the output current is linear  
with respect to the sensor input. By reversing the signs, the European convention or the  
Thermodynamic (American) convention can be defined.  
_4 mA -1000.0 mV  
20 mA 1000.0 mV  
_4 mA  
20 mA  
.00  
14.00  
3.2.7 Temperature Calibration Menu  
This Menu has two calibrate functions. It is used to adjust or trim the temperature  
compensation for variations in the sensing element. This menu can also provide a manual  
temperature input for the process. The top line displays the temperature offset value. The  
bottom line displays the adjusted temperature value.  
Trim °C  
Unit  
.0  
24.3°C  
Second, the menu is used to change the units of display to either Celsius or Fahrenheit. The  
change is performed as a toggle function and changes the displayed units on all screens or  
menus where temperature is displayed to the desired unit of measurement.  
Model LXT-230 Instruction Manual / 9  
Download from Www.Somanuals.com. All Manuals Search And Download.  
4.0 SENTINEL DIAGNOSTICS  
The basic menu structure of the LXT-230 transmitter is architecturally the same as the LXT-  
230 pH, ORP and PION, with the only variable being the diagnostic information on the main  
and special diagnostic menus. The critical path to your process measurement is via the TAI  
sensor/electrode.  
Under perfect conditions, the electro-chemical interface between the electrode’s internal  
reference cell (the measurement standard) and the liquid junction (bridge between the  
internal electrolyte and the wet process) should be in balance (stable potential values).  
However, a dominant failure mechanism of an Electro-Chemical (pH, ORP, PION)  
Reference Half Cell is insidious process contamination impacting that balance (electrode  
internal chemistry).  
Contamination from the wet process will eventually migrate through the electrode’s inner  
structure eventually changing Electro-Chemical balances via oxidation/reduction of the  
metal/metal salts and gels.  
4.1 Diagnostic set up and configuration menus  
4.1.1 Main Menu  
The degree to which the intrusive process chemicals degrades the “insitu” electrode is  
graphically depicted on the right side of the LXT-230 main process screen as a vertically  
expanding diagnostic bar, culminating in a flashing pre-pHault alert. This pre pHault Alert  
warns the user of a pending chemical alteration of the Electro-Chemical Reference  
Measurement Cell prior to the actual measurement error, hence the designation, “Pre-  
pHault.”  
pH  
_50.0%  
7.00  
25.0°C  
ORP  
25.0%  
100.0 mV  
25.0°C  
4.1.2 SENTINEL DIAGNOSTIC SCREEN  
The lower section of this (split screen – over under) menu will indicate default mV values as  
set by the factory; the default value will be 60mV in all cases. This value is Nurnstian in that  
it signifies one decade change in 4 molar reference gel. The transmitter has been designed  
so that the customer can input other mV values based on individual experience that may  
differ from the default mV number.  
Ref  
Limit  
25.2 mV  
30.0 mV  
To change the “LIMIT” values, enter the CALIBRATE MODE by simultaneously pressing the  
two horizontal CALIBRATE keys; observe the cursor move to the right allowing LIMIT value  
change. Once in CAL MODE, the cursor can be moved to different digit placements, then,  
using the vertical key, the LIMIT value can be decreased or increased based on process  
demands.  
NOTE:  
This value responds to contamination of the secondary electrolyte chamber with a Nurnstian  
response (log 10 System)  
Model LXT-230 Instruction Manual / 10  
Download from Www.Somanuals.com. All Manuals Search And Download.  
To file the input, with the microprocessor, exit the calibrate mode by pressing either menu  
selection key. The upper half of the split screen menu displays absolute reference potential  
(±2 millivolts) directly from the electrode via the diagnostic signal co conditioner located in  
the sensor. This half of the menu is “read only” and cannot be accessed.  
It is this half of the menu where you will observe the state of the electrode’s performance in  
terms of process relates aging.  
The mV LIMIT value, as set in by the user or TAI at time of shipment, may require  
adjustment from process to process due to major chemical changes that would introduce  
new electrolyte contaminants thereby impacting the rate of reference contamination in the  
electrode.  
After the desired mV values are set into the DIAGNOSTIC CALIBRATION SCREEN, further  
electrode “INSITU” diagnostic information can be obtained by scrolling to the main process  
menu where VISUAL electrode diagnostic information is displayed as a cursor/growing black  
vertical bar. As process intrusion threatens the electrode’s internal balance, the bar  
correspondingly grows in height (it will  
eventually flash as a final pre-pHault alert).  
The user can toggle between the main process screen and the dedicated diagnostic screen  
where specific, real time DIAGNOSTIC engineering data can be obtained. There is also an  
option (at time of purchase) to add a 4-20mA output card for the transmission of this  
“INSITU” diagnostic engineering data.  
Model LXT-230 Instruction Manual / 11  
Download from Www.Somanuals.com. All Manuals Search And Download.  
5.0 MAINTENANCE  
If service of the internal components is required, always turn off the power to the  
instrument.  
5.1 Cleaning  
Cleaning the front panel can be performed with a detergent and water. DO NOT USE  
ACETONE, ACID OR CAUSTIC SOLUTIONS ON THE ENCLOSURE SURFACE. If the enclosure  
cover must be removed, it is wise to clean and inspect the gasket seal. If the seal is  
damaged, replace the gasket. Always keep the gasket lightly lubricated with a silicone  
grease.  
5.2 Replacement of the Microprocessor  
Contact factory.  
Model LXT-230 Instruction Manual / 12  
Download from Www.Somanuals.com. All Manuals Search And Download.  
6.0 CALIBRATION  
6.1 Manual Output Mode  
To perform calibrations without interfering with control or recorder functions, the LXT-230  
incorporates a manual output mode. The current output is set to the desired level and saved  
until changed or released from the manual mode.  
NOTE: Prior to any calibration the LXT-230 transmitter should be placed into the  
manual mode.  
Procedure:  
1. If not at the Main Menu, press the appropriate MENU SELECTION key to reach the  
Main Menu.  
2. Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode  
and observe the "M" appear in front of the % current output value; The current  
output is now locked in the manual mode.  
3. Using the horizontal CALIBRATE keys, position the cursor under the digit to be  
adjusted.  
4. Increase or decrease the value by pressing the appropriate vertical CALIBRATE key.  
5. When the desired value is reached, exit the calibrate mode by pressing either MENU  
SELECTION key. The current output will be held at the filed value.  
pH  
M24.3%  
7.00  
25.0°C  
ORP  
M 55.0%  
-500.0 mV  
25.0°C  
To release manual output:  
1. Return to the Main Menu by pressing the appropriate MENU SELECTION key.  
2. Observe that the "M" appears in front of the % current output value. The "M"  
signifies that the output is being held at the displayed value.  
3. Press the left-hand CALIBRATE key and observe the "M" disappear, releasing the  
LXT-230 from the manual output mode. The % output value will return to the real-  
time current output.  
6.2 Contrast Adjustment  
Procedure:  
1. Press the upper MENU SELECTION key to reach the Contrast Menu (upper most  
menu).  
2. Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode.  
Observe the cursor move to the last digit.  
3. Using the horizontal CALIBRATE keys, position the cursor under the digit to be  
adjusted.  
4. Increase or decrease the value by pressing the appropriate vertical CALIBRATE key.  
5. To file the contrast value and exit the calibrate mode, press either MENU SELECTION  
key.  
6.3 One-Point Buffer Calibration (Standardize)  
Because all pH and ORP electrodes experience minor variations, buffer calibrations are  
necessary before installing the electrodes in service. Also, occasional calibrations are  
necessary to compensate for electrode degradation while in service. For measurement  
specifics, refer to the pH/ORP sensor manual.  
Model LXT-230 Instruction Manual / 13  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Procedure:  
1. Press the appropriate MENU SELECTION key to reach the Electrode Standardization  
Menu and locate the cursor under the "1" as illustrated in section 3.2.4.  
2. For diagnostic reasons note the pH and mV values from the prior calibration.  
3. Clean the electrode and insert the sensor into the desired buffer.  
4. Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode.  
Observe the diagnostic value on the bottom line change from historical data to a  
real-time value and that the term "CAL" has disappeared.  
1 pH  
7.00  
-3.2 mV@25  
1 ORP  
.0 mV  
85.9 mVa  
5. To change the buffer point, position the cursor under the desired digit using the left-  
hand CALIBRATE key.  
6. Increase or decrease the value by pressing the appropriate vertical CALIBRATE key.  
7. Wait for the real-time mV value to stabilize.  
8. To file the calibration and exit the calibrate mode, press either MENU SELECTION  
key.  
6.4 Two-Point Buffer Calibration (Span)  
When first installing an electrode, a two-point buffer calibration should be used to  
compensate for electrode slope variations or efficiency.  
Procedure:  
1. Perform a one-point calibration as outlined in section 5.3.  
2. Press the appropriate MENU SELECTION key to reach the Electrode Span Menu and  
locate the cursor under the "2" as illustrated in section 3.2.5.  
3. For diagnostic reasons note the pH and mV values from the prior calibration.  
4. Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode.  
Observe the diagnostic value on the bottom line becomes a real-time value and that  
the term "CAL" has disappeared.  
2 ORP  
180.0 mV  
.980 mV/ORP  
2 pH  
4.00  
-58.2 mV/pH  
5. To change the buffer point, position the cursor under the desired digit using the left-  
hand CALIBRATE key.  
6. Increase or decrease the value by pressing the appropriate vertical CALIBRATE key.  
7. Wait for the real-time mV value to stabilize.  
8. To file the calibration and exit the calibrate mode, press either MENU SELECTION  
key.  
A perfect electrode slope (efficiency) is -59.1 mV/pH and ORP is 1mV/mV. If the value falls  
below -50.0 mV/pH or ORP .9 mV/mV, the electrode should be serviced or replaced.  
IMPORTANT  
If a flashing asterisk appears during or after calibration, the electrode may require service,  
or the buffer solution may be contaminated. Refer to section 5.6 for details.  
NOTE:  
Comparing the millivolt values before and after the calibration provides a valuable  
Model LXT-230 Instruction Manual / 14  
Download from Www.Somanuals.com. All Manuals Search And Download.  
diagnostic tool in determining the degradation of the electrode. Large differences between  
calibrations may indicate coating or damage to the measurement half-cell.  
6.5 Calibration Using a Grab Sample as a Standard  
The LXT-230 allows easy standardization to a grab sample value by placing the process  
value into the first calibration point.  
Procedure:  
1. Record the pH value of the process when the sample is extracted.  
2. Record the pH value of the grab sample.  
3. Calculate the difference between the two values as follows:  
4. Immediately before making the calibration adjustment, note the current pH value on  
the display and add the pH differential to the current value. This "total adjusted"  
value is entered as the buffer value.  
6.6 Calibration Error Detection & Electrode Operational Guidelines  
If the slope calibration performed in section 5.4 is not within the predetermined limits of the  
instrument, a flashing asterisk (*) will appear. The presence of the asterisk indicates a  
potential calibration problem. In general, if the asterisk appears, the integrity of the  
electrode, the buffer solutions or the handling procedure should be questioned. See the  
pH/ORP sensor manual for specifics on the electrode.  
6.7 Back-to-Factory Calibration  
This feature allows the LXT-230 to be reset to "ideal electrode" (Nernst equation) for  
electrode potentials. According to the Nernst equation, an ideal pH electrode has a zero  
isopotential at 7.00 pH and a slope of -59.16 mV per pH unit, an ORP electrode has an ideal  
slope of 1 mV per ORP. This feature is useful in providing a reliable starting point if the LXT-  
230 has been mis-calibrated.  
IMPORTANT: Ideal instrumentation calibration does not imply ideal system  
calibration.  
The following procedure for returning the LXT-230 to factory calibration can be used for  
both standardize and span calibrations.  
Procedure at the Standardization Menu:  
1. Position the cursor under the "C" in "Cal."  
2. Press both horizontal CALIBRATE keys simultaneously and observe the cursor briefly  
move to the right. The default setting is complete.  
3. This procedure is required at BOTH of the calibration points.  
2 pH  
Cal  
.00  
-59.1 mV/ph  
2 ORP  
Cal  
.0 mV  
1.000 mV/ORP  
1 pH  
Cal  
7.00  
0 mV@25  
1 ORP  
Cal  
.0 mV  
.0 mVa  
6.8 Output Calibration  
The Output Calibration Menu is used to define the 4-20 mA range for the measurement. To  
change or expand the 4-20 mA range, use the following procedure.  
Model LXT-230 Instruction Manual / 15  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Procedure:  
1. Press the appropriate MENU SELECTION key to reach the Output Calibration Menu.  
2. Position the cursor on the top line to change the 4 mA point or the bottom line to  
change the 20 mA point.  
3. Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode.  
4. To change the value, position the cursor under the desired digit using the left-hand  
CALIBRATE key.  
5. Increase or decrease the value by pressing the appropriate vertical CALIBRATE key.  
6. When the desired value is reached, file the calibration and exit the calibrate mode by  
pressing either MENU SELECTION key.  
6.9 Temperature Calibration - Trim Adjustment  
When the process demands a tighter tolerance than ±3ºC the LXT-230 allows adjustment,  
or trim, of the temperature compensation element. This adjustment only compensates for  
deviations in the RTD input (as a sensor input standardize or zero adjustment).  
Procedure for trim adjust:  
1. Begin with the temperature sensing element (located in the sensor) in a solution of  
known temperature. If the temperature is not known, insert a precision thermometer  
in the same solution and allow it time to stabilize.  
2. Press the appropriate MENU SELECTION key to reach the Temperature Calibration  
Menu.  
3. Position the cursor on the top line.  
4. Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode.  
Observe the cursor move under the last digit.  
5. Position the cursor under the desired digit using the left-hand CALIBRATE key.  
6. Dial in the difference between the displayed temperature and the actual  
temperature.  
NOTE  
Make temperature adjustments slowly to allow time for the bottom line of the  
display to update. This can take 5 to 7 seconds.  
7. When the desired temperature value is reached, file the calibration and exit the  
calibrate mode by pressing either MENU SELECTION key. The value on the top line  
expresses the temperature error or deviation between the RTD and the precision  
thermometer. The value on the bottom line expresses the real-time process  
temperature.  
6.10 Temperature Units Calibration - Celsius/Fahrenheit Conversion  
The Temperature Calibration Menu is also used to change the units of display to either  
Celsius or Fahrenheit. The change is performed as a toggle function and changes the  
displayed units to the desired unit of measurement on all screens or menus where  
temperature is displayed.  
The following procedure describes how to use this feature.  
Procedure:  
1. Press the appropriate MENU SELECTION key to reach the Temperature Calibration  
Menu.  
2. Position the cursor on the bottom line under the "U" in Unit.  
3. Press both horizontal CALIBRATE keys simultaneously. Observe the unit of  
measurement change.  
Model LXT-230 Instruction Manual / 16  
Download from Www.Somanuals.com. All Manuals Search And Download.  
4. To toggle back to the first unit of measurement, press the CALIBRATE keys again.  
Trim °C  
Unit  
.0  
25.0°C  
Trim °F  
Unit  
.0  
77.0°F  
Model LXT-230 Instruction Manual / 17  
Download from Www.Somanuals.com. All Manuals Search And Download.  
7.0 LXT-230 MODEL NUMBER DESIGNATORS  
Channel 1 Input & Output  
LXT-230-PH/MA  
LXT-230-OR/MA  
UM  
PM  
HM  
Universal mounting plate  
Panel mounting hardware  
Handrail mounting plate  
(including 2” hardware)  
pH  
ORP  
Specific Ion  
(see note 1)  
LXT-230-PION/MA  
Other Options  
KSx  
Note 1: For PION, the model number will  
reflect the ion being measured; for  
example, Ca for calcium, Fl for  
fluoride, etc.  
Keyboard Security Code (x  
= level of security. See  
Security Code Option)  
Output is the function of  
two inputs: ratio,  
F2  
Channel 2 Input  
differential, average.  
Specific pH (TC for NH3 in  
condensate)  
Signal conditioner is  
mounted inside the  
PH  
OR  
pH  
ORP  
SPH  
PA  
PION  
DO  
Specific Ion (see note 1)  
Dissolved Oxygen  
transmitter enclosure  
Signal conditioner is  
mounted through the side  
of the enclosure  
Channel 2 Output  
SC  
MA  
4-20 mA, standard  
4-20 mA, 3-mode PID control  
PID  
TMP1 4-20 mA, Temperature (adjustable  
-100° to +200°C)  
ZPR  
AV  
Hazardous area Z-purge  
Field selectable time  
average (2 to 32 seconds)  
Channel 3 Output  
TMP1 Only output available on this  
channel.  
Typical Example  
LXT-230-OR/MA-PM - LXT-230 transmitter  
for use with an ORP sensor.  
Mounting Hardware  
Model LXT-230 Instruction Manual / 18  
Download from Www.Somanuals.com. All Manuals Search And Download.  
8.0 TROUBLESHOOTING GUIDE  
Symptom  
The LCD does not display.  
Possible Causes  
No power to the instrument.  
Suggested Actions  
Check power supply to be  
sure the correct voltage is  
being supplied to the  
transmitter. (13.5 to 50  
VDC)  
Check polarity of transmitter  
wiring.  
Contrast level is set too low.  
Set contrast level to a higher  
value. Because the contrast  
menu is always the top  
menu, it can be reached by  
pressing the upper MENU  
SELECTION key at least 12  
times. Enter the calibrate  
mode and increase the  
value.  
Sensor or signal conditioner  
has a short that draws too  
much power from the  
transmitter.  
Check the sensor for proper  
operation. To verify,  
disconnect all sensor wires  
and cycle power off, then on.  
The pH fluctuates from  
minimum scale to full-scale,  
The slope calibration is mis-  
calibrated. Typically the  
Check buffers to make sure  
they are the correct values.  
or the pH is locked at high or transmitter is calibrated with  
low scale.  
no slope (0 mV/pH).  
Use the Back-to-Factory  
calibration feature on the  
Electrode Span Menu, then  
perform a buffer calibration.  
Check the electrode and  
sensor for proper operation.  
Examine the temperature  
and the Temperature  
Wrong temperature  
correction has been  
calibrated in the temperature Calibration Menu. Adjust trim  
trim.  
as required.  
The pH or ORP reading short  
spans.  
The transmitter may have  
been mis-calibrated.  
Check buffers to make sure  
they are the correct values.  
Use the Back-to-Factory  
calibration feature on the  
Model LXT-230 Instruction Manual / 19  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Electrode Span Menu, then  
perform a buffer calibration.  
Check the sensor and  
electrode for proper  
operation.  
Wrong temperature  
correction has been  
Examine the temperature  
and the Temperature  
calibrated in the temperature Calibration Menu. Adjust trim  
trim.  
as required.  
LCD turns black.  
Power to the transmitter  
dropped below the minimum  
required voltage for a  
fraction of a second (gray-  
out). Typically caused by a  
voltage transient.  
Cycle power off for  
approximately 10 seconds,  
and then on again.  
Model LXT-230 Instruction Manual / 20  
Download from Www.Somanuals.com. All Manuals Search And Download.  
APPENDIX A - SPECIFICATIONS  
MEASUREMENT RANGE  
SENSITIVITY  
pH:  
0.00 to 14.00, fully expandable  
and reversible, standard. -2.00 to  
14.00 pH, optional.  
± 1.0 mV  
STABILITY  
± 0.2% per year @ 0°C to 70°C  
ORP: +1000 to -1000 mV, fully  
expandable and reversible,  
standard.  
RESPONSE TIME  
1 second to reach 90% of the change.  
OUTPUT  
4-20 mA or 20-4 mA, linear  
REPEATABILITY  
± 1.0 mV  
and expandable. Up to a maximum  
of 3 outputs.  
TEMPERATURE COMPENSATION  
POWER REQUIREMENTS  
(with zero loop impedance)  
Recommended 24 vdc  
pH:  
Automatic, -30°C to +140°C, RTD.  
Accuracy within ±0.1°C over a 0°C  
- 100°C span.  
Maximum  
Minimum  
50 vdc  
13.5 vdc  
Specific pH compensation temperature  
correction) is available. Consult the  
factory.  
MAXIMUM LOOP IMPEDANCE  
(@ 24 vdc)  
525 ohms for 4-20 mA compliance on  
primary (channel 1) output;  
approximately 800 ohms on secondary  
outputs  
ORP: Not used for compensation;  
however, temperature is displayed.  
Accuracy within ±0.1°C over a  
0°C-100°C span.  
50/60 Hz NOISE REJECTION  
Greater than 70 db  
OPERATING TEMPERATURE  
-4°F to +158°F (-20°C to +70°C)  
INPUT/OUTPUT ISOLATION  
Maximum 300 volts between process input  
and any 4-20 mA output (single  
and multiple channel outputs). No  
isolation between inputs on  
DISPLAY  
Menu driven, 32 character alpha-numeric,  
Supertwist LCD. The main menu  
simultaneously displays (1) process  
identity (2) process value (and  
engineering units), (3) percent output, (4)  
temperature in °C or °F.  
multiple channel units.  
CALIBRATION  
Auto Buffer Calibration  
Allows the definition of two buffer points,  
saved in memory, during the initial  
start-up. This will allow subsequent  
standardize and span buffer  
calibrations with only 2 keystrokes.  
ENCLOSURE  
NEMA 4X, weatherproof  
SHIPPING WEIGHT  
Standard LXT-230: 2 lbs (0.91 kgs)  
Back-to-Factory Calibration (Factory  
Restart)  
ACCURACY  
± 0.10% of full scale  
With 2 keystrokes, allows the technician  
to return the transmitter to a zero  
electrode offset (asymmetry  
potential) and to an ideal Nernstian  
slope (1.000 mV per ORP unit).  
LINEARITY  
± 0.05% of full scale  
Model LXT-230 Instruction Manual / 21  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Temperature Trim  
Allows for compensation for any  
differences in RTDs by  
programming the offset into the  
transmitter.  
Temperature Display  
Temperature can be field configured to  
display in OC or OF.  
Display Contrast  
Fully adjustable for ambient lighting  
conditions  
Model LXT-230 Instruction Manual / 22  
Download from Www.Somanuals.com. All Manuals Search And Download.  

TC electronic SDN BHD Musical Instrument Mastering 6000 User Manual
Transcend Information Stereo Amplifier 25 IDE User Manual
TRENDnet Network Router TEW 671BR User Manual
Triarch Indoor Furnishings 29321 17 User Manual
Tricity Bendix Washer AW 1201 W User Manual
Troy Bilt Trimmer TB60AF User Manual
Ultra electronic Printer Prima 2e User Manual
Uncle Milton Industries Baby Toy 152 User Manual
Univex Mixer ME130 User Manual
Vivitar Camera Accessories MagnaCam 1025x1 Digital Camera Binocular User Manual