Cause : Over voltage in deceleration comes when the drive internal main circuit DC voltage to reach or exceed the specified value.

0u2 fault in fuji FRENIC MEGA drive indicates Over voltage in deceleration. This means the DC bus voltage rises above the allowable limit because of regenerative energy feeding back into the drive while the motor slows down. The drive can't absorb the braking energy fast enough, so it trips to protect itself.

1. The protection circuit is activated to stop the inverter output.
2. The circuit may also be activated by a surge voltage produced in the power supply system.
3. Increase the deceleration time.
4. Add suitable brake devices.