12-2 NM through a hole

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480sparky said:
I wonder if I would consider that person an 'electrician' at that point. If they don't know what you need to 'see', they don't know the Code.

I don't, however, see a problem with an electrician discussing options that are available if there's an obstable or difficulty concerning an installation.
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I agree wholeheartedly, I am the frist one to discuss options avaliable or to discuss interpertations of a particular code.

What bothers me is when an electrician only wants to do "What the inspector wants" and not study and follow the code on their own.

I know a couple of electricians in my area that would rather ask me what to do then open up a code book and read it.

Chris
 
raider1 said:
........I know a couple of electricians in my area that would rather ask me what to do then open up a code book and read it.

Chris
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The woods are overrun with these guys around here! Help! :confused: :confused: :grin:
 
Gor a simple fix Im not gonna break an inspectors balls. I fix the problem quickly and everyone is happy. No wonder why inspectors cant stand People that fight that inspectors quirk. And most inspectors have a few quirks that they have a hard on about.
 
First off I think I know where the 4 cables come from. If you had 4 12/2NM cables going thru a hole that is to be fire caulk then you would have to derate. 334.80

Now look at Table 310.15(B)(2)(a) 7-9 conductors would be derated 70%. 12/2 is rated 30 amps at the 90C so we derate 70% and we still have 21 amps. Good to go but if you add a 5th cable then you must derate 50 % and NM is now good for only 15 amps.
 
Dennis Alwon said:
First off I think I know where the 4 cables come from. If you had 4 12/2NM cables going thru a hole that is to be fire caulk then you would have to derate. 334.80

Now look at Table 310.15(B)(2)(a) 7-9 conductors would be derated 70%. 12/2 is rated 30 amps at the 90C so we derate 70% and we still have 21 amps. Good to go but if you add a 5th cable then you must derate 50 % and NM is now good for only 15 amps.
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That's true, but it still doesn't make the original statement true that you can only install 4 #12 cables in a hole.
 
infinity said:
That's true, but it still doesn't make the original statement true that you can only install 4 #12 cables in a hole.
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I realize that but they say the same here. They should say more than 4 then you must derate. In most instances you are not going to want to derate below 20 amps and certainly not below 15 amps for 14/2
 
There is a requirement for fire stopped holes, is that what your boss is referreing to? If thats the case, you have to derate for fill, but the derating for 14 NM-B is from the 90 c rating of 25 amps. If you boss says its 15 amps then your installations will have to be done with 10 gage...
 
My rule of thumb is Table 310.15(B)(2)(a) - it doesnt say how many cables can be in a hole - but does tell you when you should put some distance between them when run together due to conductors of the current carrying variety.... :grin:

So - yeah four 14, or 12/2's, or three 3 wires, combinations that remain below 9 conductors per bundle going through the hole - IF the hole is big enough to accomadate said cables when pulled together without damage...... Crossing the line at nine puts you at 50% instead of 70%.
 
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e57 said:
So - yeah four 14, or 12/2's, or three 3 wires, combinations that remain below 9 conductors per bundle going through the hole - IF the hole is big enough to accomadate said cables when pulled together without damage...... Crossing the line at nine puts you at 50% instead of 70%.
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Unless they're used for switching you could put four three wires in one hole without any derated conductor issues. The neutral would not be a CCC in a three wire cable. Therefore 4- 3 wire cables would be 8 CCC's.
 
infinity said:
Unless they're used for switching you could put four three wires in one hole without any derated conductor issues. The neutral would not be a CCC in a three wire cable. Therefore 4- 3 wire cables would be 8 CCC's.
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True - but breaks my 'no more than 9' rule of thumb..... If other people see me do it, then I need to explain the meaning of life to people on a daily basis - when you make rules - stick to 'em. ;)
 
SmithBuilt said:
This is legal here and passed both building and electrical inspections.

0111081038.jpg


Tim
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...To me that is definetely not neat and the wires are not supported correctly
 
I know I am out numbered but I believe I am right....I dont believe that one romex can support another Rx cable and that is what is in the picture..
 
splinetto said:
I know I am out numbered but I believe I am right....I dont believe that one romex can support another Rx cable and that is what is in the picture..
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I take it you never stapled 2 wires together in the eaves of an attic.

Splinetto you obviously can do as you please but to condemn someone elses work for being code compliant is not right. If you can show it is a violation of the NEC then show it don't sit there and say you think it's wrong.
 
I dont believe that one romex can support another Rx cable and that is what is in the picture.
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Cables can't support other cables, but I don't see a cable supporting a cable in that picture.
 
Electrical inspectors that make their own code on misinterpret the NEC are just as bad as electricians violating the NEC. It does not matter if these gentlemen are enforcing a BETTER code, such as 2 outlets on a 20 amp circuit, wired with #10 awg for every bedroom. BECAUSE they are wrong and if they misunderstand the NEC here they may misunderstand NEC in other places, such as the electrical inspector that was having contractors put a jumper around the GFP CT. WRONG IS WRONG and if you know better and you do not stand up and point out their ignorance you are just as bad as these inspectors. Educate others and all are served.
 
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