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Motor Terminal Box clearances

Motor Terminal Box clearances

Motor Terminal Box clearances

(OP)
I tried to search the internet about what the NEC says about clearances around junction boxes specifically motor conduit boxes and I saw references to Art 314.  Nothing gave me instructions on clearances.

Art. 430-12 addresses the motor terminal housing and its details, but not working clearances around it.
Art. 430-14 requires motors to be located so maintenance can be readily be accomplished.

I believe that there isn't a strict code on clearance for motor conduit boxes as this space is never entered while energized.  Does anyone have further thoughts?

http://www.electrical-contractor.net/forums/ubbthreads.php/topics/77417/Re_pecker_Head_clearance.html

Funny thing is I struck out searching for motor conduit box clearance but I had a few hits when I called it its affectionate name "pecker head".  LOL

Thanks,

JBUDA54

RE: Motor Terminal Box clearances

Our practice considers any enclosure containing live parts as energized. So, before you
proceed to open the cover you need to open the supply breaker and to lock it. But, if you need to remove the insulation, first of all temporary protective grounds shall be placed.
In such conditions you have to assure as a minimum distance to a wall or grounded equipment according to NFPA 70E art 130.2 [and one has to add a clearance from the wall as working necessary space].
In certain instances, the Arc Flash Protection Boundary might be a greater distance from the exposed live parts than the Limited Approach Boundary. The shock protection boundaries and the arc flash hazard boundary are independent of each other [See NFPA 70E].
 

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