Hi chaps,

I'm looking for a little help with a VFD. I have a 220v Simphoenix e550 2.2kw single phase vfd - brand new along with a 40,000 rpm atc.

I can run the spindle and vfd fine when the spindle isn't grounded.

If it is grounded it trips my RCD/GFCI. I cannot bypass the rcd. The problem is the machine is grounded. If the spindle is fitted to the machine that in turn grounds the spindle which in turn kills power to our building.

The vfd was setup by the supplier on shipment. Originally we thought it might be the spindle but we changed that out and it made no difference.

I've read the manual, contacted the supplier and manufacturer and am at a loss.

Manual: https://purelogic.ru/data/docs/elekt..._manual_ru.pdf

Does anyone have any ideas?