Technical FAQs

Ask a Question

What are the probable causes of HDF fault on Altivar 71 drive.

HDF(IGBT Desaturation) fault appears only on the drive >90KW when a short-circuit is present on the IGBT module by measurement of the transistor desaturation.

Probable causes:
  • Short circuit or grounding on the output phases.
  • Transistor IGBT in short circuit
  • Check the insulation motor and the wiring.
  • There is a cabling mistake in the drive (bad connection of connector on the boards) 
  • Bad tightening of nuts on the gate drive boards 
  • Disturbances on the control cable (logic input, power removal PWR, +24V...)
  • Made transistor diagnostic.
  • Change power board, gate drive board or transistors.
Note: The insulation test on the motor and motor cables must be made at 1000V.
Was this helpful?
What can we do to improve the information ?