Industrial Engineer · phase 14 of 16
Ground Fault
Detected unintended current path from a drive output or motor circuit to ground.
The Explain card
- Plain English
- A ground fault trip means the drive has detected current leaving its output and returning through ground instead of through the other motor phases. Something between the inverter and the motor winding is leaking to earth.
- Example
- Moisture gets into a motor's junction box and one phase tracks to the frame. The drive sees the imbalance and trips on ground fault at the next start.
- Why it matters
- A real ground fault is a motor or cable problem, and a nuisance one is high frequency leakage through long shielded cable that the drive reads as a fault. Telling them apart takes an insulation tester on the motor and cable with the drive disconnected.
- Hook
- Current is going somewhere it should not, and the drive noticed.
Where it sits in the deck
Phase 14: VFD Safety, Faults, and Diagnostics
What a drive does when it trips, what the fault codes are telling you, and how safe torque off stops the motor without killing the panel.
