INS-10009982
Rev 02
Calibrating the LNG Tank Level Sensor Signal
Conditioner (LSSC)
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10. After the 3 minutes have elapsed, connect your laptop to the FDC controller inside the cab using
the RS232 patch cable. Launch WCut Software and use the standard “FDCIII-V2 DX30-
sv102.ini”. Once successfully connected, navigate to View
Analog Input Tables
Tank
Level #X where X denotes the tank you have just calibrated. This screen is shown in Figure 3.
Observe the variable Volt [V] and verify that it reads 0.5V +/- 0.1V. If this is not the case, repeat
Steps 7-9 until the voltage stabilizes to the correct value.
NOTE
If several (10 or more) attempts to calibrate low are unsuccessful, the tank may not be
suitable for use.
11. Disconnect the calibration tools, remove the key from the ignition and proceed to Stage 3.
CAUTION
Do not drive vehicle with LNG LSSC Calibration tool connected.
Stage 3: Calibration High
12. Fill the tank in accordance with Westport Work Instruction INS-10011725 LNG Truck Refueling
Instructions if filling from a fuelling station and Westport Work Instruction INS-10011129 LNG
Tank Service Kit – User Instructions if transferring a portion of fuel from a donor tank in order to
move truck to a fueling station.
NOTE
The tank may have risen to ambient temperature, making fuelling difficult. Fuelling may only take
place 5-10 gallons at a time before fuel transfer is automatically cutoff by the station.
13. Connect the LNG LSSC Calibration Tool to the LNG tank harness service calibration port
(Figures 1 & 2).
14. Insert the key into the ignition and turn to the ON position. Do not start the truck.
15. Press the Calibrate HIGH button once on the LNG LSSC Calibration Tool (Figure 1). The
calibration LED should flash once.
16. Wait at least 3 minutes before proceeding to the next step.
17. After the 3 minutes have elapsed, connect your laptop to the FDC controller inside the cab using
the RS232 patch cable. Launch WCut Software and use the standard “FDCIII-V2 DX30-
sv102.ini”. Once successfully connected, navigate to View
Analog Input Tables
Tank
Level #X where X denotes the tank you have just calibrated. This screen is shown in Figure 3.
Observe the variable Volt [V] and verify that it reads 4.5V +/- 0.1V. If this is not the case, repeat
Steps 14-16 until the voltage stabilizes to the correct value.
NOTE
If several (10 or more) attempts to calibrate high are unsuccessful, the tank may not be
suitable for use.
18. After calibrating LOW and HIGH, verify that the calibration LED is never solidly illuminated. This
indicates a calibration/system error. If this is the case, repeat the calibration procedure (Stages
2 and 3). If after repeating the procedure the LED is still solidly illuminated, the tank may not be
suitable for use.
19. Remove the calibration tools. Remove the key from the ignition.