Quote Originally Posted by Mongrel View Post
Most variable speed driven Screw Compressor packages built "Down Under" in Oz, are fitted with insulated bearings in the motor and earthing brush on the motor shaft to prevent this occurrence.
we had this problem on some of our frequency driven compressors as well, but it was only the motor bearings getting damaged.

we solved it same as Mongrel, put a copper brush on the motor shaft and grounded it on the motor base, no problem since