Cause : Overvoltage comes when the voltage supplied to the drive has exceeded the acceptable limit or there are surge voltages in the input power supply.

Voltage in the DC bus has exceeded the overvoltage detection level.
• 200 V Class: Approximately 410 V
• 400 V Class: Approximately 820 V

1. The deceleration time is too short and too much regenerative energy is flowing back into the drive.
   • Connect a dynamic braking option to the drive.
   • Perform Deceleration Rate Tuning.
2. The acceleration time is too short.
3. Make sure that sudden drive acceleration does not cause the fault.
4. The braking load is too large. Connect a dynamic braking option to the drive.
5. There are surge voltages in the input power supply. Connect a DC link choke to the drive.
6. The drive output cable or motor is shorted to ground (the current short to ground is charging the main circuit capacitor of the drive through the power supply).
   • Examine the motor main circuit cable, terminals, and motor terminal box, and then remove ground faults.
   • Re-energize the drive.