4.5 - GREEN MACHINE
™
- North America - Installation, Operation, Maintenance, & Troubleshooting Manual
Chapter 8: Troubleshooting
Page 135
8.5.1
Pressure Sensor Alarm: Troubleshooting Steps
Steps
Procedures
1. Check that a Pressure Sensor reading is showing on the Main Screen.
•
If a Pressure Sensor reading is showing on the Main Screen, go to Step 2.
•
If a Pressure Sensor reading is not showing:
a) There is no 24 VDC power to the Pressure Sensor circuit.
b) There is no signal from the Pressure Sensor at the PLC.
c) Check the Pressure Sensor power circuit as shown in
Figure 8-12
.
d) Repair the Pressure Sensor power circuit as needed.
e) If the power and signal circuits are OK, replace the Pressure Sensor.
2. Verify the Pressure Sensor signal at the PLC is below 2.5 mA.
See Figure 8-12.
a) Remove wire 04052 from the PLC, then using a multimeter, check the current
between wire 04052 and AN1 on the PLC.
b) If the signal is zero or below 2.5 mA, check to make sure the Pressure Sensor
circuit wiring is correct and tight, then see Chapter 9: Replacement Procedure
to replace the Pressure Sensor.
•
If the Pressure Sensor Alarm is still active after repairing Items 1-2, call a VST Service
Technician.
