Panasonic OCU-CR200VF5 Operating Instructions And Installation Instructions page 49

Failure Diagnosis
Failure Diagnosis of Inverter Unit
Caution
Before inspection or component replacement, always shut off the ground fault protector and take
sufficient time.
(Approx. 5 minutes are required for the capacitor to discharge)
Electrical box internal layout
(1) When the refrigeration unit stopped by activation of the ground fault protector,
possible cause is as follows. Check all of the following causes.
Cause
Compressor failure
Failure of an electric
component other than
compressor
Be sure to eliminate the cause of the failure before supplying the power (turning the ground fault
Caution
protector ON).
(Top side)
Reactor
Terminal Base for showcase
operation signal
Terminal Base for liquid tube
electromagnetic valve
Method of Checking
Check insulation resistance between each phase of
compressor and case.
Less than 1 MΩ indicates motor failure.
Check the winding resistance of the compressor.
0.97 Ω to 1.01 Ω (AT 25 °C) indicates no problem.
Check the insulation resistance between each
terminal of the INV-EN-PCB and ground (G
terminal). Less than 1 MΩ indicates insulation
failure of the INV-EN-PCB.
EN - 49
Control
terminal
base
Power source
terminal base
Method of Action
Replace the compressor
Replace the compressor
Replace the INV-EN-PCB