IGBT Desaturation
Schneider Electric · Altivar Machine ATV320 Variable Speed Drive
What does HdF mean?
A hardware detected error, specifically related to IGBT desaturation. This indicates a very high voltage drop across an IGBT, often due to a short circuit in the motor or power wiring, or an internal IGBT failure. This is a critical fault that can lead to immediate hardware damage if not addressed.
Common Causes
- IGBT (Insulated Gate Bipolar Transistor) has detected an overcurrent or overvoltage condition.
- Inadequate heatsink temperature (P1-30) leading to IGBT thermal protection.
- Power supply fluctuations (e.g., P3-01) causing IGBT stress.
- Short circuit on the motor or output terminals.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Immediately inspect motor wiring and connections for any signs of short circuits to ground or phase-to-phase.
- 2
Measure insulation resistance of the motor phases to ground and between phases using a megger (expect >1 MΩ).
- 3
Check the drive's output terminals for signs of arcing, carbon buildup, or damage.
- 4
If external wiring is verified clear, the drive's power section (IGBTs) may be damaged and require replacement.