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Old 04-04-2017, 09:07 AM   #14
rwidman
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City: North Charleston, SC
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Quote:
Originally Posted by djmarchand View Post
For those interested in this minutia, attached is a page from Charles installation instructions showing the wiring diagram. The shorepower ground is wired to a primary shield (perhaps for RF control) and is indicated to be insulated from case. The secondary (load) ground is tied to the case and the neutral side of the winding. This is allowed (and necessary) as the transformer secondary is the source in NEC terms.

I learned about all of this when I discovered that my Mainship 34T had an open ground. It turns out that when Mainship installed the isolation transformer, they never connected the ground to the case. Anyone who owns a Mainship built in the mid 2000s and has an isolation transformer should check this as others were miswired this way.

David
It's not "minutia" if you are actually installing one of these transformers. A properly installed isolation transformer is a good thing. An improperly installed isolation transformer may be worse than the original problem that someone is trying to correct.


The attachment makes it all pretty clear.
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