Conductor bundles - InspectionNews

#1 (**permalink**) 10-17-2007, 08:32 PM

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Jerry Peck · #2 (**permalink**) 10-17-2007, 08:37 PM

You can put more than 3, but you need to start derating if it goes on for 24" or more.

I see 2-2 conductor NM cables and 1-3 conductor NM cable, for 7 total. That means derating to 70% of the conductors ampacity.

Richard Rushing · #3 (**permalink**) 10-17-2007, 08:50 PM

The allowable ampacity of each conductor shall be reduced, per Table 310.15(B)(2)(a).
rr

Jerry Peck · #4 (**permalink**) 10-19-2007, 12:37 PM

Quote:

Originally Posted by dan orourke

thanks, i'll recommend builder verify if derating is needed.

If you are going to verify if derating is needed with the builder, you know what he is going to say 'Huh? Derating? What are you talking about?'

The better question is 'where do those conductors go, up the wall, through a nipple, etc.?' From there *YOU* can verify that derating is needed - except it might not be so easy as the builder may not give you enough information to go on, because he does not really: 1) know, and, 2) know what you are talking about.