partimer31

Helping out a low income senior.


Here what I am dealing with. 2" P.V.C sch. 40 conduit connected to
the top of a service breaker panel.

Customer has a roll of 250 Ft. 12-3/ground.

I am at a lost as to how to explain to him, thanks but no thanks,
I need to run THHN/THWN inside the conduit, so individual circuit
can be fuse at 20 amp. What will all the derating.

Also how do you properly secure NM-B cable to the electric service box, if
it's running out of the end of 2" P.V.C.

This job will be inspected, so I want to cross every T and dot every i.

Thanks for any opinions and comments.

MDShunk

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

Not enough details.


Here it would be a non issue.

kbsparky

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

__________________
-KB

Life is uncertain -- eat dessert first!

partimer31

The panel will be surface mounted.

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


Thanks for answering

Jim Port

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.

mcclary's electrical

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.

partimer31

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.

JohnJ0906

Check out 312.5(C) and the exception.

__________________
John from Baltimore
"One day at a Time"
All responses based on the '08 NEC
It's not my fault, it's not my problem, I'm not your solution.

Greenblinker

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.

mcclary's electrical

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.

Shado

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

__________________
- Dave ........

"Beware of the Rat....he has no Master...he works how & where he wants...."

augie47

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".