Mitsubishi Electric · A500 Inverter
This function stops the inverter output if one of the three phases (U, V, W) on the inverter's output side (load side) results in an open phase. It can also activate if the rated motor current is extremely lower than the rated inverter current, suggesting a mismatch or very light loading conditions.
Click steps to track your progress.
Check the motor wiring for continuity between phases U-V, V-W, and U-W at the inverter output terminals.
Inspect the motor for internal faults that could cause an open phase.
Verify that the capacity of the used motor is not smaller than the inverter's capacity.
Check the setting of Pr. 251 (output phase failure protection selection).