Not for me, and not for some VFDs and it's mode dependent, not sure if its adjustable via parameters in a Danfoss drive. What was the voltage of the test? At 500v on a Fluke Megohmeter, I look for >100Mohm. I have seen old V/Hz vfds that will work down to about 2-3Mohms, and my big Toshiba's won't clear the fault if the reading is less than about 120Mohm!
You should be able to power cycle the drive without opening it by removing incoming power. I suggest verifying the DC Bus during this bleed down time for safety and to note if it doesn't discharge at a nice smooth rate. I have found simple blown components in various VFD input circuits that were easier to repair in place on >50HP drives.
But all drives I have worked with consider a ground fault to be the worst of the worst kind of fault, so they force a hard power down (wait up to five minutes) and reboot. During this time, you are expected to raise the leakage resistance to an acceptable level.
Horsepower, type of conductor and rough length could be important factors as well as any local disconnects. Always disconnect the motor leads at the vfd and megger the entire circuit "as seen" by the VFD while ensuring you don't zap the poor drive output with 500-1000V, then if the readings are bad, disconnect the wiring from the motor and test each separately. Cheap wire becomes perforated with conduction when noisy VFD spikes beat on it for years. We have washdown, so local disconnects are the most frequent offenders of opne phases and ground faults, followed by breakdown of cheap wire, but by then we have often toasted the motor too.
Paul
