# Combination Panel Install



## thom (Nov 3, 2006)

A couple years back, when MD was around, he commented that the description I gave of our Combination Panel Installs would be an illegal install. I didn't have a picture at the time, now I do. 

The picture is obviously the interior with the Combination Panel directly opposite. The NM cable enter the panel through the wall in two 2" PVC male adapter fittings. The cable is properly stapled and separated prior to entry into the panel so it does not require de-rating. After installing the cable, the blank spaces are filled with foam as required by our energy code. This installation passed inspection as have all of the others. So, what (if anything) would make this an illegal installation?

The drips you see on the osb are paint. Prior to installing the panel, we mount a piece of siding, prime and paint it. The holes that penetrate the siding and OSB are primed and painted. We must do this because the stucco is not yet installed and we are not allowed to but the stucco to the panel. Air must be allowed to circulate behind the panel which is why they install stand-offs in the panel at the attachment locations.


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## 480sparky (Feb 1, 2009)

thom said:


> ..........So, what (if anything) would make this an illegal installation?.......


This:



thom said:


> ......... The NM cable enter the panel through the wall in *two 2" PVC male adapter fittings*........



*
110.3(B). Installation and Use.* Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.


Now, please don't try the "But it passed inspection" whine or play the "We've done it that way for years" card.


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## thom (Nov 3, 2006)

So what are you saying? Cable passes through male adapter fittings all the time. I know of no rule that disallows cable from passing through a fitting? 

I'm not trying to be argumentative, that's why I posted the question. Don't be obtuse, just give me a plain answer. The panels are designed for this type of installation. Cable clamp fittings would not work.


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## 480sparky (Feb 1, 2009)

thom said:


> So what are you saying? Cable passes through male adapter fittings all the time. I know of no rule that disallows cable from passing through a fitting?
> 
> I'm not trying to be argumentative, that's why I posted the question. Don't be obtuse, just give me a plain answer. The panels are designed for this type of installation. Cable clamp fittings would not work.


You asked what makes it illegal, and I told you. I just asked you NOT to play the 'We do it all the time" card.

And I *DID* give you the rule. I can't see why you think I'm being obtuse.... it's pretty easy to understand.


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## thom (Nov 3, 2006)

Are you saying that cable can only enter a box/panel with a clamp? Of course there is no clamp at a plastic box, but we must staple within 6" to accommodate that. Our inspectors apply that same rule to the installation shown, staple within 6" of entry into the fitting. 

We are required to seal the penetration to the interior without compromising the air flow behind the panel. I just don't see how to do that with clamps.

In this installation, the fitting is a sleeve, not a conduit. NM is permitted to be sleeved for short distances. In this case, the distance is about 2". I suppose we could install a box inside the wall, clamp the nm to the box, then connect the box to the panel with a couple 2" nipples but that seems silly.


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## 480sparky (Feb 1, 2009)

thom said:


> Are you saying that cable can only enter a box/panel with a clamp? Of course there is no clamp at a plastic box, but we must staple within 6" to accommodate that. Our inspectors apply that same rule to the installation shown,


Then you need to show the inspector the installation instructions and/or listing of those PVC TAs and point out where either one states they are acceptable for use with NM entering a panel or box.



thom said:


> staple within 6" of entry into the fitting.


A totally different rule. 12", actually. 334.30.



thom said:


> We are required to seal the penetration to the interior without compromising the air flow behind the panel. I just don't see how to do that with clamps.


Duct seal. Caulking. Fiberglass insulation.



thom said:


> In this installation, the fitting is a sleeve, not a conduit. NM is permitted to be sleeved for short distances. In this case, the distance is about 2".


24", if you want to get technical. Chapter 9, Note 4. If that's your claim, I'd like to see a raceway fill calculation then.



thom said:


> I suppose we could install a box inside the wall, clamp the nm to the box, then connect the box to the panel with a couple 2" nipples but that seems silly.


I still don't see why a 2" clamp won't work, other than "It's more work" or "It costs more".


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## thom (Nov 3, 2006)

You're right, a 2" romex clamp should probably work, though sealing it to the penetration would be sloppy.

Maybe the reason why the male adapter is accepted is that it is a sleeve, not much different than a romex clamp, and it allows for a softer bend. It doesn't clamp but they allow it if it is stapled within 6".


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## woodchuck2 (Feb 27, 2008)

Why not just put a the meter outside alone and the circuit panel inside?


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## thom (Nov 3, 2006)

woodchuck2 said:


> Why not just put a the meter outside alone and the circuit panel inside?


I did that for a long time. People call and a circuit is out or something needs to be modified. The panel is in the garage behind 10' of stored crap. I just didn't want to move any more crap. Outside, the panel has nothing in front of it, access is simple. 

I was talking to one of our mechanical inspectors a few years back, he lives in a subdivision I was building in, adjacent to one of my houses. I was in his garage. He had shelves installed across his electric panel. Access required emptying then removing the shelf. This was something he did, not the builder. He didn't know it was a violation. This is the same guy who quotes chapter and verse in the mechanical code. 

Several years back square D had a recall on all of the previous two (or more, I don't remember) years arc fault breakers. It was fortunate all my panels were outdoors. I just went to each house, swapped out the breakers and was on my way. If someone was home I told them what I was doing, if not I just did it and left. That was a whole lot simpler than scheduling appointments for each house.


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