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156
Faults
Fault 224: Trouble with One or More Sensors
Indicates that one or more 4-20mA sensors are not communicating or are sending a max signal to the PLC
(At least 4mA is needed on each sensor for communication to be established. 4mA=min 20mA=max).
Causes
Troubleshooting
Fixes
• Sensor is unplugged.
• Check sensor connections.
• Plug in sensor.
• Sensor is accurately reading an
abnormally high value.
• Investigate why sensor is
reading high.
• A faulty propane regulator can
cause abnormally high reading
for the propane psi sensor.
• Supply water level sensor
isolation valve closed can cause a
minimum or a maximum reading.
• Find and fix the source of high
reading.
• Sensor is damaged.
• Test with interchangeable
sensor (many sensors are
interchangeable, see sensor
page).
• Replace damaged sensor.
• One or more sensors maxed out
-Faulty sensor
-Faulty input card (Test 13)
-Faulty wire harness
-Faulty PLC
• See Test 18.
• Replace damaged sensor.
• Replace/Repair damaged wire
harness.
• Replace faulty input card.
• Replace faulty PLC.
• Multiple sensors offline
-Blown fuse (Panel 3)
-Faulty sensor
-Faulty 24 V regulator
-Faulty wire harness
• See Test 19.
• Replace blown fuse (Panel 3).
• Replace damaged sensor.
• Replace 24 V regulator.
• Replace/Repair damaged wire
harness.
• Faulty wiring
• Inspect wiring for continuity,
voltage, and ground.
• Replace/Repair faulty wiring.