NM cable wet/damp locations

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nizak

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How many here are still running indoor NM cable in a Carflex or sealtite sleeve to a piece of outdoor equipment? I have been doing it for years and never had an issue with it until now. Seems as though now we have to either transition to THHN or UF type cable for this application. Inspector is considering it a damp location and will not allow indoor NM to be used. Have I been violating the code all along, or has it just not been enforced. Thanks.
 
nizak said:
How many here are still running indoor NM cable in a Carflex or sealtite sleeve to a piece of outdoor equipment?
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I remember my master taught me to use NM when I apprenticed, but when I started working on my own, the inspectors (in a more rigorously enforced area) caused me to understand the limitation of NM to dry locations.
 
nizak said:
How many here are still running indoor NM cable in a Carflex or sealtite sleeve to a piece of outdoor equipment? I have been doing it for years and never had an issue with it until now. Seems as though now we have to either transition to THHN or UF type cable for this application. Inspector is considering it a damp location and will not allow indoor NM to be used. Have I been violating the code all along, or has it just not been enforced. Thanks.
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The code changed to say that the inside of raceways above grade is considered a damp location.
 
Little Bill said:
The code changed to say that the inside of raceways above grade is considered a damp location.
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I disagree with that, in my opinion the code has considered that a wet location for many code cycles but recently the code was changed to make it perfectly clear.
 
I don't run it in flex whips to equipment outside(use THHN), but I have sleeved it in short stubs from an outdoor panel into the attic/crawlspace above or below the panel. I'm not going to run it in conduit all the way down the side of a house or anything, even though that's not any less of a violation than what I have been doing.

I hate to say it, but we're in such dry country over here, I'll keep doing it this way until I get called on it. I hate UF, and really don't care to use it until I absolutely have too.
 
Do you transition from NM to THWN or UF when connecting to an exterior wall mount coach light/wall pack or generator power inlet box on a residential building?....or do you just run NM straight to the exterior fixture/inlet box?

Bernard
 
jumper said:
I am guessing this is it:

334.10(A) Type NM. Type NM cable shall be permitted as
follows:
(1) For both exposed and concealed work in normally dry
locations except as prohibited in 334.10(3)
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Hi Derek,

I may be wrong, but I was always under the impression that the location (damp or wet as defined in Article 100) of the box or conduit determined the type of wire to be used.

Regards,
Bernard
 
Running NM to an outdoor panel, light, etc. was never much of an issue here, at least for me, until the last year or 2. Runs starting & ending outdoors were looked at differently. NM in sealtight was done more times than I could count by everyone I worked with.

Since NM now has THHN conductors, it should be no problem to strip out & use them outdoors, but most inspectors here want to see the print, which the conductors still do not have.

I use THHN now for all outdoor conduits & boxes. I run home runs in THHN to a j box in crawl space or take UF home run to 1st device, whichever is easier. The THHN is much easier to pull in if a box is easily doable. I use NM to any outdoor device that has the box inside the wall. No one has challenged me on that. In the wall is considered inside.
 
jmellc said:
I use THHN now for all outdoor conduits & boxes. I run home runs in THHN to a j box in crawl space or take UF home run to 1st device, whichever is easier. The THHN is much easier to pull in if a box is easily doable. I use NM to any outdoor device that has the box inside the wall. No one has challenged me on that. In the wall is considered inside.
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I just want to clarify that you are using dual rated thhn-- thhn/thwn
 
Bernard1599 said:
Hi Derek,

I may be wrong, but I was always under the impression that the location (damp or wet as defined in Article 100) of the box or conduit determined the type of wire to be used.

Regards,
Bernard
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Any conduit outside is a wet location.

However, most people(including every inspector I have had) will say/allow you to punch through an exterior wall and terminate NM directly into a disco/panel/box. It has always been debatable in my mind whether this is 100% legal, but I am not bucking the system on this: It is in my favor.
 
Inside a raceway is wet location however a panel or wp enclosure is not a raceway. If an exterior panel were wet location then those breakers and terminations better be listed for wet location. I have not seen a breaker listed for damp location although their may be one.
 
NM is one topic where I want to say "A pox on all of you!"

The question boils down to: is NM safe, or not?

Personal arguments aside, let's look at the positively schitzo position of the NEC:
NM is considered proven and safe, as evidenced by the expanding acceptance of it.
NM is considered unreliable, delicate, and dangerous, as evidenced by the AFCI issue.
Modern materials make NM as water-resistant as a submarine ... yet we've disallowed its' use in even slightly damp areas.

Then there is the perennial argument about running NM in pipe, for distances short and long. Sometimes the discussions sound like missionaries arguing over which veggies the Cannibals should add to the stew pot!
 
Dennis Alwon said:
I just want to clarify that you are using dual rated thhn-- thhn/thwn
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Yes Dennis, good point. I say THHN meaning dual rated. I don't recall the last time I saw any wire that was not THHN/THWN. Some also listed MTW here & there. Now that I've said that, I will get all the odd rolls that are not dual rated & be in a mess.:)
 
Dennis Alwon said:
Inside a raceway is wet location however a panel or wp enclosure is not a raceway. If an exterior panel were wet location then those breakers and terminations better be listed for wet location. I have not seen a breaker listed for damp location although their may be one.
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So are you saying we can legitimately pass through an exterior wall directly into the back of a panel on the exterior of the wall and still use NM cable?
 
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