Service manual

Possible Cause 3: DC/DC circuit fails.

Solution: Refer to DC/DC circuit failure analysis.

Possible Cause 3: Bus voltage feedback circuit problem.

Solution: Refer to bus feedback loop problem.

 Transfer to Bypass Due to Inverter Failure

Possible Cause 1: O/P short circuit. (In this situation, no power will be transfer to O/P socket.)

Solution: Remove short circuit condition, turn off the UPS then turn on again.

Possible Cause 2: Inverter circuit failed.

Solution: Refer to Inverter Circuit failure analysis.

 Fault Due to Battery Over-Voltage

Possible Cause: Charger circuit fail

Solution: Refer to charger circuit analysis.