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#129478 - 03/30/05 01:25 PM Is my house a separately derived system?
unsaint32 Offline

Registered: 08/24/04
Posts: 16
Loc: eden prairie, MN, USA
I am confused with the definition of a separately derived system. As usual, my house is powered by a transformer on a power pole. The transformer is a isolated tranformer, right? Therefore, isn't my house a separately derived system?

#129479 - 03/30/05 05:27 PM Re: Is my house a separately derived system?
e57 Offline

Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
The wiring "within" your house is not "Seperately Derived", unless you have another transformer inside, a phase converter, or something like that. The stuff on the ploe is part of a Distribution system, all the way to the point of entry to your house. And not really covered by NEC, as much as premises wiring systems.

NEC defined it as the following:
Separately Derived System. A premises wiring system whose power is derived from a battery, from a solar photovoltaic system, or from a generator, transformer, or converter windings, and that has no direct electrical connection, including a solidly connected grounded circuit conductor, to supply conductors originating in another system.
Mark Heller
"Well - I oughta....." -Jackie Gleason

#129480 - 04/08/05 09:34 PM Re: Is my house a separately derived system?
rabowen Offline
Junior Member

Registered: 04/05/05
Posts: 4
Loc: augusta ga
If you are the power company, it is.


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