MC conductors in EMT

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JasonGSparky

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First of all, I apologize if this is an inappropriate question for this forum. To clarify, I INSIST on doing my work to code. However there has been a point where I was questioned by another electrician, and I wanted to get a group opinion on the matter. I am in no way looking for a how-to or a way to cheat or bypass code in any way, and I will change my methods accordingly if necessary to satisfy the NEC. (not to sound like a boy scout but I can't afford to make a mistake because something wasn't done to code)

MC wire. I have never ran MC through EMT conduit, except for a 12" sleeve. However, sometimes I'll buy 12/2 MC at Home Depot because its easier and cheaper than buying rolls of wire, and I'll strip down the metal shielding and plastic and push the conductors only through EMT. The electrician previously mentioned says this is illegal, because the wire is not THHN or wet rated. Upon looking at the wire, there are no markings, however the plastic covering the conductors does say THHN THWN rated.

The easiest thing to do is just buy the spools. The customer ends up paying for materials in the end, so its not a big deal. But If I can save $50 or so here and there by buying MC, I would like to continue doing that.
What is the proper thing to do?
 
Although the conductors may be unmarked they are 90° C dry conductors. Technically they should be surface marked when installed in a raceway. Some companies do mark surface marked conductors within MC cable.
 
When you say you strip off the armor and liner, is that from end to end of the MC or just on one end?

Whichever way, it is what it is. If the conductors are THHN/THWN according to the liner labeling then that's what they are. But if an inspector looks at the conductors, how is he supposed to determine what the conductors are. How many will accept an electrician's word? If you get a hardliner inspector, he will insist on the insulation being marked. See 310.120.

If you strip just one end, the liner in the unstripped section proves it is THHN/THWN.
 
Is stripped MC cable really cheaper than individual rolls of wire? Not to mention the extra labor.
 
I use short sections of 12AWG mc, up to around twenty feet, stripped and shoved in conduit or wire mold all the time. Sometimes it's still sheathed at the other end, but not always. It's a ticky tack violation if the conductors aren't individually marked but I'm not worried about it.
 
I always strip and sleeve MC cable in EMT when it's called for. Nothing wrong with it at all. The only people that have an issue with it are people with too much time on their hands that like to argue about it on code forums.
 
The OP is not stripping and changing the MC cable over to EMT he is completely removing the outer jacket and using the individual conductors in EMT.
 
infinity said:
Is stripped MC cable really cheaper than individual rolls of wire? Not to mention the extra labor.
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I was curious also.

A 250 ft roll of 12/2 MC at home depot is $88.97 which yields 750 ft of #12 solid (counting the bare ground) which is 0.11862 cents per foot.

A 500 foot roll of #12 solid is $46.37 which is 0.09274 cents per foot.

So not cheaper even when not factoring in labor and ruined wire.
 
Coppersmith said:
I was curious also.

A 250 ft roll of 12/2 MC at home depot is $88.97 which yields 750 ft of #12 solid (counting the bare ground) which is 0.11862 cents per foot.

A 500 foot roll of #12 solid is $46.37 which is 0.09274 cents per foot.

So not cheaper even when not factoring in labor and ruined wire.
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You must mean MC-ap. Can you use the bare #10 as an EGC? How do you terminate it?
 
Coppersmith said:
If you are that keen on doing work to code (and who isn't in this forum:roll:), stripping the conductors out of any pre-made cable is iffy code violation wise.
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I understand that everyone here is 100% code-oriented, just like everyone in prison is innocent lol. I believe everyone takes a slight shortcut here and there, but I was simply pointing out in that opening statement that I wasn't trying to find a cheap work-around or gray area. I've just noticed a lot of posts are closed because of violating the forum's terms of service, and I didn't want this post to sound like a "how-to" or something.

Stripping the conductors from MC is sometimes easier and cheaper, depending on the situation. There are times where I'm on a call, and instead of going to get material I can just pull out 25' of MC, strip it back, and push it through conduit. I used to carry rolls of wire, but I rarely used them as I was mostly running MC and romex. I have to be selective about how much material I carry, as I don't have a ton of space (extended cab Ford Ranger with bed-mounted tool box).

Thanks for all the replies, and the code reference as well. I was aware of marking conductors for where they go, I guess I just glossed over the part about actual writing on the insulation!
 
Coppersmith said:
I was curious also.

A 250 ft roll of 12/2 MC at home depot is $88.97 which yields 750 ft of #12 solid (counting the bare ground) which is 0.11862 cents per foot.

A 500 foot roll of #12 solid is $46.37 which is 0.09274 cents per foot.

So not cheaper even when not factoring in labor and ruined wire.
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I agree its not always going to be the cheapest or easiest solution, but consider this...
A conduit run from the panel in the garage to the post lights at the end of a driveway is 125'. Cut wire at Home Depot at about $.29/ft is about $36x3 conductors = $108 minimum. In this instance I can save at least $20 and still have the rest of the 250' roll to take with me. (Of course, I could purchase the 500' roll, stretch it out to 3 lengths, and phase tape the ends, save a lot more money and still have some wire)

Southwire has this tri-pull 3-wire deal thats 350' for around $100 I think.
 
JasonGSparky said:
I agree its not always going to be the cheapest or easiest solution, but consider this...
A conduit run from the panel in the garage to the post lights at the end of a driveway is 125'. Cut wire at Home Depot at about $.29/ft is about $36x3 conductors = $108 minimum. In this instance I can save at least $20 and still have the rest of the 250' roll to take with me. (Of course, I could purchase the 500' roll, stretch it out to 3 lengths, and phase tape the ends, save a lot more money and still have some wire)

Southwire has this tri-pull 3-wire deal thats 350' for around $100 I think.
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So, you would consider stripping 125' of MC just to get the conductors inside? :lol:

You can try and justify this all day long but the fact is it's a code violation. We've heard from guys here that ran NM to an A/C disconnect on the outside of the building then stripped the jacket off another six feet and pulled the conductors into the sealtite whip. AHJ spotted it and gave them a violation.

So if you're a stickler for the Code as you say you are do it right and stop being so cheap.

-Hal
 
Just playing devils advocate, what is the opinion of the members here of leaving the wrapper that is marking the conductors as THHN in place when pulling it into the EMT? That is the difference between stripping MC & NM cables
 
JasonGSparky said:
However, sometimes I'll buy 12/2 MC at Home Depot because its easier and cheaper than buying rolls of wire, and I'll strip down the metal shielding and plastic and push the conductors only through EMT. The electrician previously mentioned says this is illegal, because the wire is not THHN or wet rated. Upon looking at the wire, there are no markings, however the plastic covering the conductors does say THHN THWN rated.
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I agree with the others in that I can not see it being a cheaper alternative over single conductors but, why not just push or pull the MC through the EMT intact?

Roger
 
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