romex in conduit

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rickl

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hi, i need some ideas on a 200 amp service change i looked at today. its a old outdoor panel with a 2" conduit LBing into the crawl space with 14 romex cables in it and 3 romex cables ran on the outside of the house (they probably wouldn't fit in the conduit so they just ran them exposed). so i need some ideas on how to get all those cables into the new outdoor panel. at first i thought i'll just run 3 2" conduits but after further review that won't work due to conduit fill and 310-15 ( the conduits will be over 24" )
i can only have 4 12-2 cables per 2" conduit. and i have 13 12-2wg ,2 10-2wg & 2 6-3wg plus what ever they want to add while i'm there. is it legal to run romex to a junction box then strip the outer jacket off and run the conductors in conduit from junction box to panel. also on 334-15(b)is it saying i can't use schedule 40 pvc conduit from panel to crawl space? i know the easiest way would be to install the panel on the inside of the house but the homeowner doesn't want the panel in the dining room. i thought about a junction box on the outside of the house but that it wouldn't good .
so any ideas would greatly be appricated
 
Re: romex in conduit

Put your junction box in the crawl, terminate the NM in the junction box, and run THHN to the new panelboard. Check the derating first. :D
 
Re: romex in conduit

I don't think there is any provision in the code to strip off the outer jacket and run romex conductors as individual conductors.

<added> to reduce the number of wires being run from the jbox to the panelboard you could add a ground bar and insulated neutral bar to the jbox and run two big wires back to the panelboard for those wires.

[ February 19, 2005, 08:54 AM: Message edited by: petersonra ]
 
Re: romex in conduit

Originally posted by petersonra:
you could add a ground bar and insulated neutral bar to the jbox and run two big wires back to the panelboard for those wires.
Click to expand...
Not to sure you can move the neutral bar into the jbox.

It is allowed under certain circumstances.

300.(B)(4) Enclosures. Where an auxiliary gutter runs between a column-width panelboard and a pull box, and the pull box includes neutral terminations, the neutral conductors of circuits supplied from the panelboard shall be permitted to originate in the pull box.
Click to expand...
 
Re: romex in conduit

I am not suggesting moving the existing neutral bar, but rather running a big wire white wire down to the new jbox and terminating it at a new insulated neutral bar. the new bar is just for convenience. consider the new neutral bar as a substitute for a big wire nut connecting the little white wires to the big white wire.
 
Re: romex in conduit

Originally posted by petersonra:
I am not suggesting moving the existing neutral bar, but rather running a big wire white wire down to the new jbox and terminating it at a new insulated neutral bar. the new bar is just for convenience. consider the new neutral bar as a substitute for a big wire nut connecting the little white wires to the big white wire.
Click to expand...
In theory your idea is sound as long as the grounded conductor (white wire) is sized properly.

rickl:
The local AHJ may freak out upon seeing that. Check first. When in doubt keep it simple and continue each grounded conductor down to the panelboard. You can run multiwire circuits up to the jbox and then split to two wire circuits to reduce the number of grounded conductors. Since it's single phase the grounded conductors of a multiwire circuit would not count in the derating.

If you run the romex down a large conduit you may end up with a larger or more conduits than you want to run than if you ran individual conductors. Remember the general rule is NM must terminate in a connector marked for the number of cables.
Charlie's suggestion would 99.9% guarantee you pass inspection with no grief.
Of course if the original installation passed, then it looks like almost anything goes ;)
 
Re: romex in conduit

I'm curious why you think an inspector would "freak out"?

This is not any different than running a big white wire out to a sub-panel and branching out from there. As long as it is sized adequately.
 
Re: romex in conduit

I think he or she might freak out because it's not what they are used to seeing. Some of our guys would.
Or they know just enough to be dangerous and throw out "Is that jbox listed for the installation of a neutral buss."
Or you get show me in the code where it says you can do that.
 
Re: romex in conduit

Charlie has best answer.Perhaps use #10 if derating becomes a problem.You might point out to customer that out door panels usually dont hold up as well.Hang picture over panel
 
Re: romex in conduit

Tecgnically this would not be legal. I have known some AHJs that would just consider the conduit as a means of protecting the wire outside. On the other hand some inspecters would absolutely turn it down. I would use Charlies suggestion.
 
Re: romex in conduit

Iwire,

Thank you for all the information you have given me.

quote:
--------------------------------------------------
300.(B)(4) Enclosures. Where an auxiliary gutter runs between a column-width panel board and a pull box, and the pull box includes neutral terminations, the neutral conductors of circuits supplied from the panel board shall be permitted to originate in the pull box.
--------------------------------------------------
What does it mean by "column-width panel board"? I always thought that you couldn't terminate all the grounded conductors and connect to a large conductor then install to panel board. What table would you use to size the grounded conductor appropriately? I recall that there was an article to under size the grounded conductor but I don't remember it offhand and I'm not sure if it applied.

Thank you
Justin
 
Re: romex in conduit

Originally posted by cpal:
justinjwalecka

Column width panel boards typicall are narrower than a standard tub or load center and designed for installation within the web of a steel I column such as on warhouse floors

Charlie P
Click to expand...
While these are nice when you need them, they are an absolute BEAR to wire up and work in, because of the lack of space. CH, GE and Siemans also make them.
 
Re: romex in conduit

thanks for the help, i guess i'll try to talk them into going with the panel in the dining rm if not i'll be under the house splicing conductors together. doesn't that sound like fun
 
Re: romex in conduit

Would anything not permit using an A/C line cover to cover NM and it can be secured within required distance from the top of the panel.Is this a wet location , no direct contact with water run off or spray ???Not U.L. listed for this purpose ?? But neither is drywall above a panel listed for protecting from physical damage as NM enters a panel ;)
 
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