# NM-B cable run inside 2" conduit



## MDShunk (Jan 7, 2007)

Install a j-box on the end of the PVC, where ever that might end, and run the 12-3 from there. 

There is one exception for running a pipe nipple out of the TOP of a surface panel if it doesn't go through a ceiling or floor, and you just staple within 12".


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## 220/221 (Sep 25, 2007)

Not enough details.


Here it would be a non issue.


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## kbsparky (Sep 20, 2007)

Is the panel surface or flush mounted? How long is that piece of PVC conduit? Are there any other cables installed in there?


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## partimer31 (Jun 9, 2009)

The panel will be surface mounted.

The conduit will run to just before the ceiling about 6 Ft. in length.


Thanks for answering


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## Jim Port (Oct 1, 2007)

Robert,

I think it would be helpful to you to read thru the NEC so you can better understand your options both doing electrical work and also home inspections.

There are instances where derating would not necessarily apply, nor would the cables need to be fastened to the enclosure.


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## McClary’s Electrical (Feb 21, 2009)

Code allows the original installer to run a 2" PVC from the first floor, to an attic, for future ease of accessing the panel. So that part is legal. Derating has to apply for more than 3 ccc's. If you're running one 12/3 for a mwbc you don't need to derate. If you're concerned about securing the cable, your way out would be to run thhn. I try to avoid using sheathed cable in conduit, but when I do, I usually just strip sheath back so it cannot be seen in conduit.


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## partimer31 (Jun 9, 2009)

Thanks to all you guys that have taken the time to post a reply.

I have the job, and I'll be starting it in one weeks time.

I just glad there people out there that like to share their knowledge.


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## JohnJ0906 (Jan 22, 2007)

Check out 312.5(C) and the exception.


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## Greenblinker (Aug 4, 2008)

mcclary's electrical said:


> I try to avoid using sheathed cable in conduit, but when I do, I usually just strip sheath back so it cannot be seen in conduit.


Just curious about what everyone thinks about this practice - stripping the outer jacket off the nm-b before running it in conduit. I don't see how it would hurt anything as long its an interior installation, but i have heard people argue that it defeats the UL listing by doing that. I know I have done it plenty of times, but i still hesitate every time.


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## McClary’s Electrical (Feb 21, 2009)

Greenblinker said:


> Just curious about what everyone thinks about this practice - stripping the outer jacket off the nm-b before running it in conduit. I don't see how it would hurt anything as long its an interior installation, but i have heard people argue that it defeats the UL listing by doing that. I know I have done it plenty of times, but i still hesitate every time.


A sharp inspector will catch it. Yes, when stripped, there are no ratings on the wires of a NM, So when, you remove sheath, you remove ratings. But IMO, it doesn't hurt anything. I touch a wire and can tell you what size it is, I don't need a sheath.


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## Shado (Jan 1, 2009)

Has a reason been stated as to why there is no rating on the NM conductors themselves?


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## augie47 (May 4, 2009)

mcclary's electrical said:


> Code allows the original installer to run a 2" PVC from the first floor, to an attic, for future ease of accessing the panel. So that part is legal. Derating has to apply for more than 3 ccc's. If you're running one 12/3 for a mwbc you don't need to derate. If you're concerned about securing the cable, your way out would be to run thhn. I try to avoid using sheathed cable in conduit, but when I do, I usually just strip sheath back so it cannot be seen in conduit.


Unless terminating in a j box, this appears it would be a violation of 312.5(B). Am I wrong ??
With deratimg in mind, I would see little use for it to be a 2".


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