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Posted By: frank isolated ground system, sorta i think - 08/12/02 09:22 PM
I was sent to wire a 220v 30a receptical in a phone room.At the panel i see two grounding bars,one sandard and one isolated.The standard is not used and there is no standard or isolated ground wires from source or load to it.The isolated grounding bar is almost full with a mixture of insulated and bare ground wires.
All the recpticals are orange with black and red.Since the isolated ground would be compromised by the bare ground wires ect.I don't understand the concept but i have seen it in old hospital O.R's for line isolation monitors where they ran 12/2 bx with the bare ground bonded to the box then the isolated grounding screw on the plug?
Posted By: Bjarney Re: isolated ground system, sorta i think - 08/29/02 08:54 PM
There are all kinds of so-called isolated-ground bars, and these too can be {seriously} misunderstood and misapplied. [Such ‘accepted’ practices are not automatically the best from a electrical-power engineering or ‘legal’ standpoint.] Also, telecomm practices generally far predate the introduction of 'orange-faced' wiring devices.

The next step would be to precisely determine the need based or the current published installation manual for the device being powered. Whatever someone says, or regardless of any arm waving in the process, standing published information should turn the key.
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