Siemens Micromaster 440 Fault F002 — What It Means
F002 on a Siemens Micromaster 440 means the drive has tripped on overcurrent. The output current exceeded the safe threshold, usually during acceleration, a load shock, or because of a shorted motor circuit.
Common Causes
- Acceleration ramp too short. The most common field cause.
- Motor shaft or driven machine is jammed. Bearings, gearbox, or belt issues cause immediate current spikes.
- Shorted motor cable or grounded motor. Damaged insulation looks like an overcurrent event.
- Wrong motor parameters. Incorrect P0304, P0305, or P0310 values can destabilize control.
- Failed IGBT module. If the fault appears with no motor connected, the drive is likely damaged.
Step-by-Step Fix {#fix}
- Increase ramp time. Check acceleration parameters and lengthen the ramp significantly.
- Inspect the driven machine. Disconnect the motor from the load if possible and test again.
- Megger the motor and output cable. Low insulation resistance means motor or cable failure.
- Verify motor parameters. Confirm rated current, power, voltage, and frequency match the nameplate.
- Run motor identification / commissioning if the drive was recently replaced or reprogrammed.
- Check the output stage. Persistent F002 with the motor disconnected usually means a failed IGBT section.
Parts Often Needed
| Part | Notes |
|---|---|
| Motor cable | Amazon | Use shielded VFD cable for long runs |
| Replacement motor | Amazon | Needed if windings are grounded |
| Micromaster 440 drive | Amazon | Replace if output module is shorted |
When to Call a Pro
If F002 trips under light load with correct parameters and a healthy motor, the drive likely has an internal hardware failure.