Recessed Lights J Boxes

[electricmanscott]

What do you mean by this? I thought this was forum to learn by asking question and getting your years of experience

Oops. Thought I was in the election results forum.

 

[raider1]

Moreover, the contactor but the cables thru a knock only with no connector. And that this was ok per the listing.:-?

Are you saying the contractor ran the NM cable through a knock out that did not have a factory installed cable clamp?

The point I am trying to make is that the factory installed knockout with the integeral cable clamp would not need any additional protection according to the NEC.

HERE is a link to the installation instructions for the type of Juno can that I am talking about.

Chris

 

[buckle40]

Yes, that is what I am saying. And the code says that this should be a smooth edge and securely fastened. Where as the cable can be pulled out with no effort if you use the manufacture clamp. The knock out is not smooth there for it needs a bushing or clamp per 314.17 B

 

[raider1]

Yes, that is what I am saying. And the code says that this should be a smooth edge and securely fastened.

I agree, you can't just install a NM cable into a standard knock out with out some sort of cable clamp to attach the cable to the box.

Where as the cable can be pulled out with no effort if you use the manufacture clamp. The knock out is not smooth there for it needs a bushing or clamp per 314.17 B

If you use the manufactures designed knock out with the cable clamp that comes factory installed IMHO you do not need to do anything else.

Chris

 

[kgettrost]

Does not the Nec Supersede a manufactors specs when it tales you to check with the AHJ.

 

[roger]

Does not the Nec Supersede a manufactors specs when it tales you to check with the AHJ.

Where does the NEC tell anyone to check with the AHJ?

The NEC actually tells us we must abide by the manufacturers instructions, see 110.3(B)

Roger

 

[roger]

BTW, welcome to the forums.

Roger

 

[celtic]

Does not the Nec Supersede a manufactors specs when it tales you to check with the AHJ.

This is some sort of circular logic...

:-?

 

[LJSMITH1]

Yes, that is what I am saying. And the code says that this should be a smooth edge and securely fastened. Where as the cable can be pulled out with no effort if you use the manufacture clamp. The knock out is not smooth there for it needs a bushing or clamp per 314.17 B

Forget the NEC in this instance! The Mfr's instructions clearly define the installation requirements. If the installer put the NM cable into the STANDARD knockout and not the special NM knockout with the pre-installed clamp, they are clearly not installing the fixture according to manufacturers instructions.

To fix it you could either pull out the NM and reinstall into the correct knockout and plug the other knockout, OR pull out the NM and use a standard NM fitting (plastic push in or strap-type snap-in). Either way, you need to pull out the NM and reinstall correctly. Period.

This is not a trick question or a challenging problem...:roll:

 

[LarryFine]

I firmly believe the OP is asking about the spring-clamp all-metal kind of cable retainer you use when you pry out the small KO at the edge of the bends in the J-box metal. The plastic slide-in grips barely do, but they're obviously not metal or sharp.

In spite of someone's opinion that the metal tang doesn't qualify as smooth or rounded, they do grip the cable without damaging it, unless you pull too hard on the cable without releasing the pressure (which ie easily weakened if you're not careful.)

Almost any cable clamp will damage the cable if you try, but I've never seen these clamps damage a cable upon proper installation. That's what they're made for, and I'd fuss at any of my guys if they used anything else with NM. It's my time and money.

 

[electricmanscott]

I firmly believe the OP is asking about the spring-clamp all-metal kind of cable retainer you use when you pry out the small KO at the edge of the bends in the J-box metal. The plastic slide-in grips barely do, but they're obviously not metal or sharp.

In spite of someone's opinion that the metal tang doesn't qualify as smooth or rounded, they do grip the cable without damaging it, unless you pull too hard on the cable without releasing the pressure (which ie easily weakened if you're not careful.)

Almost any cable clamp will damage the cable if you try, but I've never seen these clamps damage a cable upon proper installation. That's what they're made for, and I'd fuss at any of my guys if they used anything else with NM. It's my time and money.

Eaxactly. This is just a case of somebody making a big stink about nothing.