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SG-38MARB-01 Specifications subject to change without notice.
49
DIAGNOSIS AND SOLUTION (CONT)
Over voltage or low voltage protection (PC01)
Description:
Abnormal increases or decreases in voltage are detected by checking the specified voltage detection circuit.
Recommended parts to repair:
• Power supply wires
• IPM module board
• PCB
• Reactor
Troubleshooting
Check the power supply.
Is it in working order?
Turn off the unit.
NO
Check the connections and wires.
YES
Are they in working order?
Ensure the proper connections
or replace the wires.
NO
Power on and measure the
voltage between P and N.
YES
Replace the IPM board.
NO
Check the reactor.
YES
Is it in working order?
Replace outdoor PCB.
NO
Replace the reactor.
YES
While the unit is in the standby mode,
is the voltage between P and N around
DC 310V, 340V or 380V?
At unit start up, is it
220V~400V?