Isolated Ground

[spsnyder]

I have an isolation transformer (240V:240/120V) for sound equipment in a performing arts center. Should I bond the isolated ground conductor to the ground system at the transformer or pass through the transformer and bond the isolated ground conductor at the service entrance panel's grounding system?

Also, Is it acceptable to size the isolated ground conductors as you would any other EGC? Thank you for your help.

Scott

 

[dereckbc]

Re: Isolated Ground

The IG originates from the isolation transformer, not a panel upstream of the transformer. The whole purpose of the isolation transformer is to establish a new ground point free of common mode noise. Your isolation transformer is required to have the Xo terminated to the nearest ground electrode per 250.30. This will establish your new ground point for EGC and IG if required.

All EGC's are sized the same.

[ April 21, 2004, 04:12 PM: Message edited by: dereckbc ]