F034 fault in WEG CFW900 Drive indicates an IGBT V Desaturation. This means the V-phase power module experienced a severe overcurrent or short circuit, triggering an immediate hardware shutdown.
Cause:
- Short circuit between the motor phases V and U or V and W.
Remedy:
Inspect output motor cables and motor terminal box for short circuits between phase V-U or V-W. If motor connections are correct, verify IGBT state.
