Thanks aolalde!
Herein lies the reasoning that X4 could possibly ground, if internally in the drive L2 is somehow connected to the chassis for grounding purposes. I suppose this is possible?
I want to use a 480/240:120 stepdown xfmr to feed my reliance single phase DC regen drive. If I connect X1 & X4 to the drive as the 240V supply, and X3 & X2 to ground, will I be able to use X1 & gnd as the control circuit power for the drive? My concern is that X1 & X4 will be floating...