Maximum # Conductors in 1" EMT

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Alwayslearningelec

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NJ
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Estimator
I know this but I'm getting two different answers based on a calculator and table C.1 Chapter 9.

Adhering to 30% fill

#10 THHN I get 12 in one and 16 in another. I assume the NEC table which says 16 is not taking 30% fill into consideration.
 
Where are you coming up with 30% fill ?
Over two conductors is a 40% allowance.
 
Alwayslearningelec said:
#10 THHN I get 12 in one and 16 in another. I assume the NEC table which says 16 is not taking 30% fill into consideration.
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16 is the correct answer but as Augie stated the maximum fill percentage for 3 or more conductors is 40%. When is doubt you can always go old school and look at the physical Table C1 in Annex C.
 
Alwayslearningelec said:
Revisiting this. Do you guys ever really pull 16 #10's THHN in 1" EMT?
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I've seen it done as long as you use stranded conductors but imo it's not a good design unless the runs are very short. We once had a job spec of #10 solid and the lay out man had 18-#10's in a 1" EMT (he said grounds don't count). They has to use a super tugger to get the wire in and the force was so great that the large 45° offsets in the run near the tugger actually star started to straightened out.
 
infinity said:
I've seen it done as long as you use stranded conductors but imo it's not a good design unless the runs are very short. We once had a job spec of #10 solid and the lay out man had 18-#10's in a 1" EMT (he said grounds don't count). They has to use a super tugger to get the wire in and the force was so great that the large 45° offsets in the run near the tugger actually star started to straightened out.
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wow... I am surprise the wires didn't snap.
 
electrofelon said:
Actually thinking about it, I bet that's pretty common that # 10 home runs are speced, so what do you guys usually do in that case for quantity and pipe size?
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I prefer 1.25" home runs. With #10's and 20 amp circuits you can get up to 20 CCC's without derating getting you below 20 amps.
 
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