Romex in conduit?

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Fbarr24

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I have ran a 2" pvc from outside surface mounted panel to an LB with about 6" of pvc into the attic of a house. Can I run my romex homeruns(14 ckts) down the conduit to the panel? or should I put a 12 x 12 box in the attic and run THHN wires down the conduit and leave the romex in the attic and splice them in the box?
 
Welcome to the forum.

Technically, the former method is not compliant, but often done and accepted, stapling close to the nipple.

Some say that stripping the sheath makes it okay, despite the conductors having no printed identification.

The latter method is certainly compliant, with conductor-quantity derating kept in mind; maybe two conduits.
 
So if I put a bell end on the nipple in the attic and staple wires to the joist within 12" I should be fine? Or should I just put a box and run THHN down the LB to the panel?
 
LarryFine said:
Welcome to the forum.

Technically, the former method is not compliant, but often done and accepted, stapling close to the nipple.

Some say that stripping the sheath makes it okay, despite the conductors having no printed identification.

The latter method is certainly compliant, with conductor-quantity derating kept in mind; maybe two conduits.
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While having NM in a technically wet/damp location is a violation, it is a much lesser safety factor than the second suggestion but a violation none the less, and moisture wicking in the paper of the NM is very real issue.
Code allows NM to be in conduit (dry location) but only as a whole cable assembly (not stripped of it's sheathing) and extending into the enclosure a minimum of 1/4 inch to allow for identification of paired conductors for neutral (personally I would leave it even longer, easier to identify pairing).
OP already suggested best option in his second option and is the most compliant means, also can reduce conduit fill because you can bond all grounds in Jbox and can run a single EGC to the panel. 250.122(C) gives size information when doing so. But also must remember to have all the paired H/N identified as they exit the conduit into the panelboard. Personally I also would suggest providing identification of location of the single splice point of all the circuit at the panelboard, helps next guy with troubleshooting in future (hopefully far into future).
 
LarryFine said:
Welcome to the forum.

Technically, the former method is not compliant, but often done and accepted, stapling close to the nipple.

Some say that stripping the sheath makes it okay, despite the conductors having no printed identification.

The latter method is certainly compliant, with conductor-quantity derating kept in mind; maybe two conduits.
Click to expand...
If splicing in the junction box one can also increase conductor sizes if needed for adjusment factors. Also can put a EGC bar in the box and lessen fill a little by not having so many EGC's. If all the cables are 12 and 14 AWG you only need one 12 AWG EGC in the pipe, or even use the pipe as EGC it were metallic.

And fact it is outdoors brings in the aspect of NM not rated for wet locations as well.
 
First off thanks for the info everyone. I think what I'm going to end up doing is putting a 10 x 10 weatherproof box outside with a EGC bar and run the Hots and N down with one ground to the panel. Probly going to add another 1" pipe down to panel for additional circuits in the future. Open to any other ideas if anyone has any input? stay safe everyone
 
Wouldn't routing 14 circuits together cause a 50% derating due to cable bundling? I'm dealing with a similar issue myself but it's horizontal run across a conditioned knee wall storage space.
 
Some states allow you to run romex in conduit outside for about 6'. North Carolina is one of them. You can check with your state to see if it's allowable there as well. About routing 14 circuits together causing a 50% derating. I believe there is an exception to that as well for very short runs.
 
Mgarf33 said:
Wouldn't routing 14 circuits together cause a 50% derating due to cable bundling? I'm dealing with a similar issue myself but it's horizontal run across a conditioned knee wall storage space.
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Actually if 14 two wire circuits you have 28 CCC's and the adjustment is 45%.

Or as mentioned keep it to 24 inches or less and you don't have to make adjustments
 
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