MC cable (not burial rated) OK to bury if sleeved?

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VirutalElectrician

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Location
Mpls, MN
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Sparky - Trying to be retired
I have a surplus of 2-2-2-6 MC cable that I'd like to use up for a sub panel. About 80' needs to go interior then about 30' underground.

The MC itself is not rated for burial, but the individual conductors are THWN.

According to the 2020 NEC, MC can be used in any raceway, and can be used in a wet location if the MC has a anti-corrosion coating and the individual conductors are rated for wet location.

It appears this is an acceptable configuration, except that the anti-corrosion coating requirement might be the sticking point.

Thoughts?
 
Doesn't sound like standard MC cable meets #11:

330.10(11) In wet locations where a corrosion-resistant jacket is provided over the metallic covering and any of the following conditions are met:
a. The metallic covering is impervious to moisture.
b. A jacket resistant to moisture is provided under the metal covering.
c. The insulated conductors under the metallic covering are listed for use in wet locations.

Can't you just strip the jacket off?
 
I did chat with my AHJ. He said I could not sleeve the MC inside of PVC if the MC was not rated for a wet location even if the individual conductors were.

I then asked about stripping off the MC and transitioning it in a junction box.

He said he couldn't recommend it, or suggest it, as that would be converting it from one listed use to another. But he said, once I did that, and sleeved it in PVC, the only thing he would be allowed to look at would be if the individual conductors were THWN or not, and if they were, there would be nothing to fail it on.

So it looks like that's my solution.
 
I did chat with my AHJ. He said I could not sleeve the MC inside of PVC if the MC was not rated for a wet location even if the individual conductors were.

I then asked about stripping off the MC and transitioning it in a junction box.

He said he couldn't recommend it, or suggest it, as that would be converting it from one listed use to another. But he said, once I did that, and sleeved it in PVC, the only thing he would be allowed to look at would be if the individual conductors were THWN or not, and if they were, there would be nothing to fail it on.

So it looks like that's my solution.
There's no conversion going on there. There's absolutely nothing wrong with using the markings on the conductors that are in the MC once you terminate the MC.
 
He's correct in that "inside a conduit" is not a location. The cable or conductors are wherever the conduit is.
 
One thing to be very sure of: are the individual conductors _marked_ as THWN.

I believe MC sometimes comes with individual marked conductors but sometimes the marking is on a strip run with the conductors.

Guess what unmarked conductors are good for.....

Jon
 
He's correct in that "inside a conduit" is not a location. The cable or conductors are wherever the conduit is.
300.5 doesn't agree:
300.5(B) Wet Locations. The interior of enclosure or raceway installed underground shall be considered a wet location. Insulated conductors and cables installed in these enclosures or raceway in underground installation shall comply with 310.10(C)
Also:
Doesn't sound like standard MC cable meets #11:
330.10(11) In wet locations where a corrosion-resistant jacket is provided over the metallic covering and any of the following conditions are met:
a. The metallic covering is impervious to moisture.
b. A jacket resistant to moisture is provided under the metal covering.
c. The insulated conductors under the metallic covering are listed for use in wet locations.

Can't you just strip the jacket off?
If you are going thru the trouble of stripping the cable (presuming the conductors are labeled) and providing a box to reconnect the MC sheathing so to continue as an MC run, why not just run the properly listed wire in the underground and splice at the junction box, that you will be needing anyways, to transition back to the MC?
Also to re-insert the conductors onto the MC sheathing at one end or other near impossible if you are trying to avoid splices and using the conductors without the sheathing within the conduit section underground (presuming appropriate labeling on the conductors). I've tried to pull long length of sheathing off before and it doesn't work, and trying to make shorter cuts of sheathing to pull off has often resulted in damage to the conductors while trying to control the loose wire and the sharp edge of the sheathing.
The MC I have here the conductors are not individually marked, it has a marking tape inside with conductors.
 
I see no issue with removing the armor and pulling the conductors in the raceway as it's done all of the time. Larger MC Cable is pretty easy to strip.
 
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