Grounding NM connectors????

[A/A Fuel GTX]

And I know an EC that got called on that. He had to ground the plate-- this was before we had the round plastic blanks for lights.

I guess it's the AHJ's call but I just don't see how it is likely to be energized.....

 

[Dennis Alwon]

I guess it's the AHJ's call but I just don't see how it is likely to be energized.....

You put a wire nut on the wire in the box stuff it in the box and the wirenut falls off and touches the metal plate. Unusual and unlikely someone would touch a plate in the middle of a ceiling and be grounded but that vacuum extension could do it.

 

[romeo]

Grounding NM connectors

Grounding NM connectors

I guess it's the AHJ's call but I just don't see how it is likely to be energized.....

Check out 404.9(B)

 

[A/A Fuel GTX]

You put a wire nut on the wire in the box stuff it in the box and the wirenut falls off and touches the metal plate. Unusual and unlikely someone would touch a plate in the middle of a ceiling and be grounded but that vacuum extension could do it.

Maybe we should change the verbage to read "likely to become energized when pigs fly"

 

[Dennis Alwon]

Okay so this definitely appears to be an ahj call. I was thinking what is likely to be energized. I would bet that everyone hear knows someone who has overtightened an nm cable clamp and shorted it out. I must say I have never done so but I have had employees that have and I know many people who have---so does that mean it is likely to be energized. Not likely if I do it-- does that count .

 

[A/A Fuel GTX]

Not likely if I do it-- does that count .

You bet........:wink:

 

[inspector141]

Heck, look at how many table lamps are metal or at the very least have a metal clad socket, and they only have a 2 wire cord. I realize that portable lamps are outside the scope of the NEC, but you get my point.

Good point!

 

[don_resqcapt19]

It doesn't matter if the NM connector is likely to become energized, it is required to be bonded by 250.4(A)(3).

 

[LarryFine]

I guess the bottom line is that the cable clamp should match the box: metal for metal and plastic for plastic.

 

[iwire]

It doesn't matter if the NM connector is likely to become energized, it is required to be bonded by 250.4(A)(3).

I disagree with that broad statement.

IMO a NM connector does not 'enclose' electrical conductors. The sheath is enclosing the conductors.

 

[LJSMITH1]

"Likely to become energized" can mean different things in different contexts. In this application, the likely way that the fitting would become energized is by poor workmanship (i.e. incorrect stripping or damaging of sheath on NM) or installation practice (i.e. NM pulled tight enough 90 degrees to fitting to damage insulation)

The bottom line is that if the standard fitting is rated for NM, and used in a dry location, or a location where no additional corrosion protection is required, then it would be acceptable to use with a PVC box....IMHO..

 

[M. D.]

Well at first I thought ,.." Oh good God not another switch is an outlet thread":smile: But at the same time ,..I am required to bond metallic blanks on plastic junction boxes.

 

[MASTERFRANK]

Some plastic or pvc boxes are to thick to use snap in plastic connectors. Making the metal romex connector the only choice on the truck.