Cause: Overvoltage comes when the voltage detected by the drive exceeds its maximum allowable level. This alarm trips when the voltage on the DC bus of the VFD exceeds a certain threshold. 

dc overvolt a7 danfoss indicates an overvoltage condition. This means the drive is receiving a voltage higher than its specified maximum rating.

Troubleshooting Steps:

Follow these steps to resolve dc overvolt a7 danfoss problem:

• Check the AC line voltage supplied to the VFD with a multimeter to ensure it is within the specified range for the drive.
• Increase the deceleration time (make the ramp longer) in the drive's parameters. This will give the motor more time to slow down and reduce the rate of regenerative energy.
• Check the parameters related to dynamic braking in the drive's settings. Ensure they are configured appropriately for your application.
• Observe when the alarm occurs (e.g., during deceleration, constant speed, changing load). This can provide clues to the cause.