Fault Finding - Grundfos Control MPC Installation And Operating Instructions Manual

10. Fault finding

Warning
Before starting fault finding, switch off the power
supply for at least five minutes. Make sure that the
power supply cannot be accidentally switched on.
Fault
The system has stopped and
cannot restart.
Possible cause
Primary sensor is defective.
Cable is broken or short-circuited.
Power supply is disconnected.
CU 352 is defective.
Power supply is disconnected.
Main switch is switched off.
Main switch is defective.
Motor protection is activated.
Remedy
Replace the sensor.
Transmitters with 0-20 mA or 4-20 mA output
signals are monitored by the system.
Repair or replace the cable.
Connect the power supply.
Contact Grundfos.
Connect the power supply.
Switch on the main switch.
Replace the main switch.
Contact Grundfos.
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