Conduit fill

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AVD001

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I am working under NEC 2002. I am feeding a 100 amp main lug sub panel with 3 #3THHN in a 1" rigid nipple. The inspector is saying I am over on the wire fill but when I go table 8(c) and look up the number of conductors it states 3. Am I missing something here?
 
Re: Conduit fill

Do you have a ground wire in the nipple?

If so you need to calculate the cross sectional area.

(3) Equipment grounding or bonding conductors, where installed,
shall be included when calculating conduit or
tubing fill. The actual dimensions of the equipment
grounding or bonding conductor (insulated or bare)
shall be used in the calculation.
 
Re: Conduit fill

Nipples 24" or less can be filled to 60% of their cross-sectional area. Look at Chapter 9 Tables NOte (4).
RMC at 60% can be filled to .532 in sq.
#3 has a diameter of .0973 in sq
(.0973)(3)=.29 in sq.

Sounds like you could put more conductors in there if you so choose. Also if you were to use the table for RMC as you've stated, which is figured at 40% you would still be OK with 3-#3 THHN conductors.
 
Re: Conduit fill

I did not have to pull a ground wire and the nipple is 6" long. I thought I was right but I did not have the code book with me duting the final inspection. Thanks for your help.
 
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