Transitioning from THWN to NM

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Old 07-11-19, 11:09 AM
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Transitioning from THWN to NM

Wiring a sub panel. Running THWN #2 awg wire in 2" conduit. Then will splice to 2-3 NM and make the run to the main panel. From what I've read code says the length of the junction box has to be 8 x the largest raceway. Since I'm using 2" conduit that means my junction box has to be 16" long.

Can I use this box for a junction box?

https://www.zoro.com/wiegmann-straig...nk/i/G0504813/

Of course I have to add end caps.

TIA
 
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Old 07-11-19, 11:49 AM
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Yes, you can use a wireway or gutter like the type you posted.
 
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Old 07-11-19, 03:31 PM
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Thank you ibpooks

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Old 07-11-19, 04:29 PM
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For splicing NEC specifies 6 times, not 8, so 2" conduit needs 12" box.

See NEC 314.28(A)(2)
 
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Old 07-11-19, 06:07 PM
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Oh, good, even better. Thanks pattenp
 
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Old 07-11-19, 06:58 PM
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For splicing NEC specifies 6 times, not 8, so 2" conduit needs 12" box.

See NEC 314.28(A)(2)
If it is a straight pull it is 8x the largest pipe plus the sum of the other pipes. U or angle pulls it is 6x the largest pipe plus the sum of the other pipes.
 
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Old 07-11-19, 08:46 PM
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I believe the sum of the other raceways is only of those entering the same wall or row of the box. If it's one in and one out on a different wall it's just the 6 times the largest conduit entering the box.
 
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Old 07-12-19, 05:54 AM
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I wish they would use zEnglish when they write NEC . It sure would reduce confusion.
 
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Old 07-12-19, 04:10 PM
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If it's one in and one out on a different wall it's just the 6 times the largest conduit entering the box
If it is one in and one out on opposite walls (straight pull) it is 8x the largest conduit. Yes, the sum is if there are more then one conduit on a side of a box.
 
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Old 07-12-19, 10:13 PM
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He said he was doing a splice, not a straight pull, so it's 6 times.
 
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Old 07-13-19, 06:13 AM
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Yes. I'm only stating the complete requirements..
 
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Old 07-15-19, 05:19 AM
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Thanks for the help.

TimH
 
 

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