Plastic grommets needed with MC Cable?

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kroelec

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Building Insp (not Electrical Inspector) has told the General Contractor we are working with, that all of the holes in the sheet metal studs that we used to run our MC cable must have plastic grommets. I have never heard of this has anyone else? Thanks in Advance!
 
Plastic grommets needed with MC Cable

Plastic grommets needed with MC Cable

kroelec said:
Building Insp (not Electrical Inspector) has told the General Contractor we are working with, that all of the holes in the sheet metal studs that we used to run our MC cable must have plastic grommets. I have never heard of this has anyone else? Thanks in Advance!
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No never heard of it ask for a code section.
 
Something we see often is no clue to where your at and yes it does change answer.Personally i think it helps grounding by not having them bushings.Ask for code violation and if smart he will back off because he has none.Tell him his mommy is calling him.
 
Jim W in Tampa said:
Personally i think it helps grounding by not having them bushings.
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Please explain: What a bushing has to do with MC grounding?


I believe the OP is talking about these things:
1284_151.jpg

http://www.erico.com/products/CADDYESGP.asp
 
Jim W in Tampa said:
.Personally i think it helps grounding by not having them bushings........
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Are you suggesting that if the grommet is not installed that the actual physical contact of the metal sheath will provide additional "grounding'? :-?

That the weight of the cable laying on the surface of the knockout in the metal stud will actually provide additional, dependable, reliable, redundant grounding? :-?

If so, I disagree. :smile:
 
I have never used a grommit with MC. Look at 300.4(B)(1), the grommit rule in metal studding only applies to NM and ENT. Then go to 330.17, and you will see that 300.4 (B) is not included in the protection rule.
 
I have used them in metal studs before, not because of any code or inspector, but it does make it easier to pull MC through the studs
 
wbalsam1 said:
If so, I disagree. :smile:
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Fred, I think that's what Jim's saying, and I agree.

Since it's not required, it can't exactly be inferior - so every little bit helps.

Down in Florida, they've started requiring steel studs to be bonded (through connection to metallic outlet boxes and so forth) after a worker was electrocuted by a doorjamb.
 
wbalsam1 said:
That the weight of the cable laying on the surface of the knockout in the metal stud will actually provide additional, dependable, reliable, redundant grounding? :-?

If so, I disagree. :smile:
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Would that be because the sheath is probably not listed as an EGC ...
 
mc and metal studs

mc and metal studs

nope just had a job passed that did just that no no no. i personally as an inspector would require gromets for romex but not mc.
 
georgestolz said:
Fred, I think that's what Jim's saying, and I agree.

Since it's not required, it can't exactly be inferior - so every little bit helps.

Down in Florida, they've started requiring steel studs to be bonded (through connection to metallic outlet boxes and so forth) after a worker was electrocuted by a doorjamb.
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Thats exactly what i am saying.While it might not be a good connection it still helps with grounding.After you get several studs touching mc i am sure it has low impedance to the stud.It was not needed but cant hurt.
 
As far as bonding the metal studs, that sounds like a good idea. Isn't this accomplished by the equipment grounding conductor being connected to the metal box, which in turn is fastened to the metal stud? These would be considered "thorough connections".....

I also think it's a great idea to install the grommets when using an armored cable, even if not required....

I'm an advocate of "thorough" connections and as such would never subscribe to the notion that the physical weight of something pressing on metal could be figured in as a contributing factor toward bonding or grounding.

As far as getting off the focus of the op, 30 lashes...:smile:
 
DAWGS said:
How would metal boxes be an approved method of bonding to metal studs when your using self taps to mount them?
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Would self-tapping screws of an adequate length provide a thorough connection? I would think they would. So they would be thoroughly connecting a box to a metal stud. The box would be thoroughly connected to the equipment grounding conductor. This would provide a continuous metallic path which would be electrically conductive. These thorough connections would in turn ensure electrical continuity, so that if a fault were to occur at a metal stud, somehow, this system would have the capacity to safely conduct such a fault. :smile:
 
georgestolz said:
Down in Florida, they've started requiring steel studs to be bonded (through connection to metallic outlet boxes and so forth) after a worker was electrocuted by a doorjamb.
Click to expand...

I thought it was from a dryer receptacle that had faulted.
 
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