Applicable Systems
AC500
AC590
ACS580
ACS880
Symptoms
The drive trips and the fault LED is lit. The display shows F0002 indicating DC overvoltage. The DC bus voltage has exceeded the safe operating limit.
Possible Causes
- Deceleration time too short causing regenerative overvoltage
- Regenerative energy from the load exceeds braking capacity
- Brake chopper or resistor not connected or faulty
- Supply voltage too high or voltage transient on the input
Troubleshooting Steps
- Step 1: Check the deceleration time parameter in the drive settings
Deceleration time allows the regenerative energy to dissipate safely - Step 2: Verify the brake chopper and resistor are connected and functional
Brake resistor resistance and power rating match the drive requirements - Step 3: Measure the input supply voltage at the drive terminals
Supply voltage is within the drive rated range - Step 4: Increase the deceleration time or add an external braking resistor
DC bus voltage stays within safe limits during deceleration
How to Reset
To reset: 1) Fix the cause of the overvoltage (increase deceleration time, add/fix brake resistor). 2) Press RESET on the control panel. Caution: Repeated overvoltage trips can damage the DC bus capacitors. Always address the root cause before restarting.
Frequently Asked Questions
- Q: Why does my drive trip on overvoltage during deceleration?
When the motor decelerates, it acts as a generator, feeding energy back into the DC bus. If the deceleration time is too short or the brake resistor is absent or undersized, the DC voltage rises above the trip threshold.
- Q: How do I size a brake resistor?
Calculate the regenerative power based on the load inertia and deceleration time. Select a resistor with sufficient continuous and peak power capacity. Refer to the ABB drive manual for sizing formulas and tables.
Source: ABB ACS880 Firmware Manual, 2023
Category: PLC & VFD