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Discussion Starter #1
Just moved into this house and was noticing the garage lights as I was drinking beer. The cable has an internal ground wire. Please excuse my ignorance. I do instrumentation and control work as a job, but don’t get into this side of it. Asked one of our electricians at work and all he said was “I’ve seen worse pass”. Thanks for all of your help.
153026
 

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Discussion Starter #3
Yeah I plan on pulling it down and redoing it in the future. Have higher priorities first.
 

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Just moved into this house and was noticing the garage lights as I was drinking beer. The cable has an internal ground wire. Please excuse my ignorance. I do instrumentation and control work as a job, but don’t get into this side of it. Asked one of our electricians at work and all he said was “I’ve seen worse pass”. Thanks for all of your help. View attachment 153026
As long as the ground wire in the cable is connected to a ground wire in the ceiling box.
 

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I assume a non metallic box so will need a means to bond the MC to EGC per NEC 314.3
 

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Arsholeprentice
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Is it code, no.
Am I losing sleep over it, no.

That would be pretty low on my priority list
 

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Discussion Starter #7
It is a non-metallic box. The ground is hooked up to the ground wire in the ceiling box and hooked up the lighting fixture housing. Would the armored cable not be grounded through the fitting to the housing then to the housing being grounded? Sorry if this sounds like I’m trying to debate you guys being correct. Just trying to learn something since I don’t really get into this to much.
 

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Hackenschmidt
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I assume a non metallic box so will need a means to bond the MC to EGC per NEC 314.3
I have never really understood the exceptions

314.3 Nonmetallic Boxes. Nonmetallic boxes shall be permitted only with open wiring on insulators, concealed knob-and-tube wiring, cabled wiring methods with entirely nonmetallic sheaths, flexible cords, and nonmetallic raceways.

Exception No. 1: Where internal bonding means are provided between all entries, nonmetallic boxes shall be permitted to be used with metal raceways or metal-armored cables.

Exception No. 2: Where integral bonding means with a provision for attaching an equipment bonding jumper inside the box are provided between all threaded entries in nonmetallic boxes listed for the purpose, nonmetallic boxes shall be permitted to be used with metal raceways or metal armored cables.
 

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Although MC Cable is not considered an EGC per NEC 250.118 the non current carrying metal clad still needs to be bonded to the EGC to maintain continuity.
 

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It is a non-metallic box. The ground is hooked up to the ground wire in the ceiling box and hooked up the lighting fixture housing. Would the armored cable not be grounded through the fitting to the housing then to the housing being grounded? Sorry if this sounds like I’m trying to debate you guys being correct. Just trying to learn something since I don’t really get into this to much.
It probably is, electrically, but it also looks like an NM clamp on the MC so that's probably not code. I agree that it should function fine and be safe regardless.
 

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The mc is bonded thru the fixture equipment grounding conductor. I don't see a violation as long as everything is bonded properly, I have never seen a blue blank either unless that is plastic wrap on a metal plate.
 

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The mc is bonded thru the fixture equipment grounding conductor. I don't see a violation as long as everything is bonded properly, I have never seen a blue blank either unless that is plastic wrap on a metal plate.
That is what you're supposed to use to blank off a claron box because if you used a metal blank, you would have to bond it.
 

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Hackenschmidt
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The mc is bonded thru the fixture equipment grounding conductor. I don't see a violation as long as everything is bonded properly, I have never seen a blue blank either unless that is plastic wrap on a metal plate.
I don't see a huge hazard but I don't see how the MC fitting and MC armor are bonded unless someone bothered to put a bonding locknut inside there.

I don't see how this is compliant because I don't understand WTF the exceptions are talking about.
 

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Hackenschmidt
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OK help me out here.

314.3 - Exception No. 1: Where internal bonding means are provided between all entries, nonmetallic boxes shall be permitted to be used with metal raceways or metal-armored cables.
I think this one they are talking about bonding bushings or bonding locknuts, OK.

314.4 - Exception No. 2: Where integral bonding means with a provision for attaching an equipment bonding jumper inside the box are provided between all threaded entries in nonmetallic boxes listed for the purpose, nonmetallic boxes shall be permitted to be used with metal raceways or metal armored cables.
Is this actually a thing? Plastic boxes with threaded hubs with bonding lugs built in and a trace between all the lugs / hubs? Sounds silly.

WAIT a minute. Frankly this sounds Canadian to me.

Is this some kind of Canadian infiltration into the NEC? The Canadian plastic manufacturers want to hop on the NEC gravy train and sell us code mandated twenty dollar plastic boxes* or something? I don't like the sound of this.

* Excuse me, fifty loony plastic boxes.
 

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Plastic box- plastic cover- mc cable which has an equipment grounding conductor and it is bonded to the light- light fixture being bonded now bonds the mc
 

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Hackenschmidt
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Is it possible the code requirement wants that armor bonded even when the fixture is somewhat disassembled?
 

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Discussion Starter #20
Thanks for all the input guys. I won’t worry to much about it based on all your info. I was more worried it was a homeowner install that didn’t know what he was doing. I understand that the NEC code doesn’t always make sense. I was also curious why the separate grounding conductor hooked up the the fixture housing wouldn’t provide a good ground to the armored cable if there was bare metal where the mc cable enters. I mean if you have next to no resistance between the ground that was landed on the fixture all the way over to the plastic box wouldn’t that mean that it is fairly well bonded and negate the needed for a bonding bushing? Just curious.
 
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