f30021 fault in siemens drive

The F30021 fault on a Siemens Sinamics drive (G120, S120, G130)

indicates a Power Unit Ground Fault. It means the drive has detected a short circuit to ground on the output side, often caused by damaged motor cables, insulation failure in the motor windings, or a defective motor module/current transformer (CT).

Common Causes for F30021

• Motor Cable Fault: Short circuit in the motor cable to ground or damaged shielding.
• Motor Winding Failure: Insulation failure within the motor.
• Defective Power Unit/IGBT: The inverter module (IGBTs) is damaged.
• Defective CT/Module: Current Transformers (CT) inside the drive have failed.
• Environmental Factors:
  Excessive moisture, dust, or condensation in the terminal box

 

Troubleshooting Steps

1. Check Motor and Cables: Disconnect the motor cables from the drive and run the drive. If the fault disappears, the issue is in the motor or cable. Use a megger to test motor phase-to-ground insulation.
2. Inspect Connections: Verify that the motor cables are properly connected and that the shielding is properly grounded.
3. Check Power Module: If the fault persists with the motor disconnected, the Power Module (IGBT/CTs) is likely defective.
4. Check 24V Supply: Ensure a stable 24V DC supply is connected to the Control Unit.
5. Review Parameters: Check if motor data in the drive matches the actual motor, especially for
   
   control scenarios.