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#184631 - 02/14/09 08:25 PM Disconnect at secondary of transformer
Rhiney Offline
New Member

Registered: 02/12/09
Posts: 3
Loc: California
Hello there!
I've got a situation here where we are setting a 112.5kva480x 120/208 transformer on the roof of a building.
It will supply power to a 400Amp MCB-type panelboard below roughly 40'of conduit and wire away.
Are we required to have a fused disconnect near the transformer (word has it wthin 25')? Where in the code is this requirement if it exists?
Primary overcurrent protection is a 175amp circuit breaker.
Thanks much for any help

2014 / 2011 NEC & Related Books and Study Guides
#184632 - 02/14/09 08:41 PM Re: Disconnect at secondary of transformer [Re: Rhiney]
Yoopersup Offline

Registered: 03/04/03
Posts: 826
Loc: Michigan
Read which one applys in this section for you.
Also read Table 450.3(B).

Edited by Yoopersup (02/14/09 08:44 PM)

#184633 - 02/14/09 09:41 PM Re: Disconnect at secondary of transformer [Re: Yoopersup]
Rhiney Offline
New Member

Registered: 02/12/09
Posts: 3
Loc: California
Thanks much Yoopersup.
That cleared it right up for me . A fused disconnect within 25ft it is .


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