Wiring for single phase drive 1

[ejmartin]

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. Therefore, when I ground the drive chassis will it mess up the drive? Please advise.

 

[aolalde]

My opinion: If X3 & X2 are grounded, then X1 and X4 are not floating, they have now a reference to ground. Now, not X1 nor X4 can be connected to ground (if for whatever reason it should be required), because you will create a short circuit to ground.

 

[ejmartin]

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?

 

[Barry1961]

This may be off the path.........

I have used DC regens that the control voltage, 10vdc, inputs would have a high voltage potential to ground. This caused a particular problem with the analog input command which was referenced to ground in our controller. ZAP went a quad op-amp! The best solution we had at the time was to isolate each drive with it's own transformer 1:1 from ground.

As I said this may be off path but your questions seem to indicate your having a gounding problem of some kind. What problems are you having?

Barry1961