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Can Ventilated Transformers be supplied with a factory installed isolated insulated ground bus ?

Issue:
Isolated Ground Installation

Product Line:
LV Transformers

Environment:
Applies to Low Voltage Transformers by SquareD/Schneider Electric

Cause:
Applications which require an Isolated Ground connection for Electronic Equipment and other specialized loads

Resolution:

Due to the wide variation of grounding requirements, supplying an isolated grounding bus is the contractor`s responsibility.  Contractors are sometimes required to create an isolated ground, or IG system at the transformer secondary. Many installers have conceptual problems with IG systems.
Some think that it means that the secondary neutral is not grounded, others interpret that a separate ground bar is required in the transformer. Neither of these are correct.
To originate an IG ground wire at the transformer, simply carry a separate, IG ground conductor from the equipment ground point in the transformer to an isolated ground bar in the secondary panel.
The isolated ground and the equipment ground originate from the same ground point within the transformer, where they are bonded to building ground, but remain separated in the panel and in all branch circuits.
The purpose of isolated ground is to provide a single point ground for all load point receptacles, rather than the multiple grounds and potential ground current loops associated with a traditional, daisy chained equipment ground schemes.


 
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