The code 3210 in your ABB ACS800 drive indicates a fault related to excessive intermediate circuit (DC link) voltage. This is a critical fault as high DC voltage can damage components within the drive.

1. Check that overvoltage controller is on (parameter 20.05).
2. Check supply voltage for static or transient overvoltage.
3. Check brake chopper and resistor (if used).
4. Check deceleration time.
5. Use coast-to-stop function (if applicable).
6. Retrofit frequency converter with brake chopper and brake resistor.