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A motor control center used indoors in a corrosive environment shall be?

this question was on a practice exam i was taking today at school. The answer turned out to be 6P. Where can I find this information in the code...I have looked for 20 minutes now and nothing. Thanks

nick.
430.91
thanks a lot

it's funny how stuff just slips right by you in the book

thanks again

nick
I would have thought that a NEMA-4X enclosure would work.
I may have seen that question. I don't think any of the "X"s were an option. Funny how some test questions never go away.
Sorta like the 120v 1hp motor and the 14 ga wire.
I'm sorry, but that answer was wrong, unless if it were a multiple choice question and 4X was not a choice, then it is just less wrong than any other choice would have been.

430.91 does NOT address "Motor Control Centers" by the way, it is referring to "Motor Controllers", as in individual motor controllers. There is NO SUCH THING as a NEMA / UL 6P Motor Control Center! There are a few companies who might make a NEMA 4X stainless steel MCC and Moeller used to make a plastic MCC (but only UL type 12), but none of them will have UL 4X, the testing cost would be astronomical and I don't even think UL-845 (the standard for MCCs) even addresses 4X testing! Also, the only difference between 4X and 6P is 6P's ability to be submerged, which was not addressed in the question. Whomever made that test question up should be subjected to a 6P test...

[This message has been edited by jraef (edited 07-26-2006).]
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