HdF

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.

Complete Troubleshooting Guide

  1. 1

    Immediately inspect motor wiring and connections for any signs of short circuits to ground or phase-to-phase.

  2. 2

    Measure insulation resistance of the motor phases to ground and between phases using a megger (expect >1 MΩ).

  3. 3

    Check the drive's output terminals for signs of arcing, carbon buildup, or damage.

  4. 4

    If external wiring is verified clear, the drive's power section (IGBTs) may be damaged and require replacement.