# Bonding bushing



## ICE (Feb 20, 2012)

Should the lock ring be removed before the bonding bushing is threaded on?


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## fireguy (Feb 20, 2012)

If the nut is not removed,

1. Where do you get a nut to secure the connector to the box?

2. When you do find another nut, there will not be enough threads to securly tighten the fitting to the box.

Now, can I have my wire strippers?


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## Gregg Harris (Feb 20, 2012)

I do believe it requires a lock ring on both sides.


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## ICE (Feb 20, 2012)

Gregg Harris said:
			
		

> I do believe it requires a lock ring on both sides.


This is a residential service 120/240.  I'm pretty sure that double lock rings don't come into play unless it is over 600 volts.  But don't take my word for it, ask an electrician.


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## jar546 (Feb 20, 2012)

Why is there a bonding bushing on that?


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## ICE (Feb 20, 2012)

jar546 said:
			
		

> Why is there a bonding bushing on that?


That is a grounding electrode conductor that has armor sheath protecting it.  Every end of the armor shall be bonded to the GEC.  Before this panel was done, there were four more bonding bushings, one for each conduit.


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## ICE (Feb 20, 2012)

Sometimes it doesn't matter.  If anyone can access the listing I would like to know about the lock ring.  I guess I can go to Home Depot and see how they fit together.

What do you west coast electricians do?  (I don't think they do it this way back east.)


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## Pcinspector1 (Feb 21, 2012)

The OP picture by ICE, Is it permitted to drill a hole anywhere in the box or are you suppose to use the knock-outs?

pc1


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## codeworks (Feb 21, 2012)

you can drill a hole in the top, sides or bottom, as long as you've got proper wire bending space, room for fitting and locknots, and grounding bushings if req'd


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## Dennis (Feb 21, 2012)

codeworks said:
			
		

> you can drill a hole in the top, sides or bottom, as long as you've got proper wire bending space, room for fitting and locknots, and grounding bushings if req'd


Just to be clear- this is a weather proof enclosure so entry above the busbar would not be compliant with this type cable since the connectors would not be able water tight.


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## chris kennedy (Feb 21, 2012)

I can't find the listing, yet here is some food for thought.

1)  I researched 3 manufactures of bonding bushings all 3 state for use on RMC IMC. So again IMO the use of one on a MC fitting violates 110.3(B). Here is a link to one.

2) There is a sentence in 300.4 that would lead me to believe a metallic bonding bushing is not required to secure a raceway to an enclosure.



> 300.4(G) Insulated Fittings. Where raceways contain 4 AWG or larger insulated circuit conductors and these conductors enter a cabinet, box, enclosure, or raceway, the conductors shall be protected by a substantial fitting providing a smoothly rounded insulating surface, unless the conductors are separated from the fitting or raceway by substantial insulating material that is securely fastened in place.Exception:  Where threaded hubs or bosses that are an integral part of a cabinet, box, enclosure, or raceway provide a smoothly rounded or flared entry for conductors.
> 
> Conduit bushings constructed wholly of insulating material shall not be used to secure a fitting or raceway. The insulating fitting or insulating material shall have a temperature rating not less than the insulation temperature rating of the installed conductors.


3) Again your regional use of 3/8 FMC for this install seems to be in violation of 348.20.



> 348.20 Size.(A) Minimum. FMC less than metric designator 16 (trade size ½) shall not be used unless permitted in 348.20(A)(1) through (A)(5) for metric designator 12 (trade size ).
> 
> (1)     For enclosing the leads of motors as permitted in 430.245(B)
> 
> ...



And in closing, the following pic is from the 2008 NECHB and is courtesy of a manufacturer of bonding bushings. No lock nut required.






[/QUOTE]


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## codeworks (Feb 21, 2012)

i don't get pictures, filters


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## Dennis (Feb 21, 2012)

chris kennedy said:
			
		

> And in closing, the following pic is from the 2008 NECHB and is courtesy of a manufacturer of bonding bushings. *No lock nut required.*


But using a locknut is also not a violation.


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## chris kennedy (Feb 21, 2012)

Dennis said:
			
		

> But using a locknut is also not a violation.


Yes sir, I certainly agree with you.


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## chris kennedy (Feb 21, 2012)

codeworks said:
			
		

> i don't get pictures, filters


Buy your IT guy lunch.


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## Gregg Harris (Feb 21, 2012)

chris kennedy said:
			
		

> I can't find the listing, yet here is some food for thought.1)  I researched 3 manufactures of bonding bushings all 3 state for use on RMC IMC. So again IMO the use of one on a MC fitting violates 110.3(B). Here is a link to one.
> 
> 2) There is a sentence in 300.4 that would lead me to believe a metallic bonding bushing is not required to secure a raceway to an enclosure.
> 
> ...


Are we looking for the UL. and CSA listings? UL file # E3060 and CSA file # LR2884.

UL 514B UL467


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## ICE (Feb 21, 2012)

Thanks gentlemen,

I appreciate the time you have spent on this.

Our use of FMC to protect a GEC is becoming more suspect by the day.  The use is widespread here in Ca.

The clamp in the picture has a listing and I wonder if this clamp was developed specifically for this application because I don't see any other use for it.  I don't know what the listing says and as wrong as I've been in the past I won't be taking any bets.

Looking at the conduit fittings, I don't see enough threaded material to screw on a bushing unless the lock ring is removed.


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## Dennis (Feb 21, 2012)

I don't believe that clamp is rated for that purpose.  I am pretty sure of that.


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## Gregg Harris (Feb 21, 2012)

ICE said:
			
		

> Thanks gentlemen,I appreciate the time you have spent on this.
> 
> Our use of FMC to protect a GEC is becoming more suspect by the day.  The use is widespread here in Ca.
> 
> ...


Galvin Electrical "The clamps are used to connect armored cable to water pipe for grounding."

UL and CSA listed


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## ICE (Feb 21, 2012)

250.64

(B)

it shall be in rigid metal conduit, intermediate metal conduit, rigid nonmetallic conduit, electrical metallic tubing, or *cable armor*. Grounding electrode conductors smaller than 6 AWG shall be in rigid metal conduit, intermediate metal conduit, rigid nonmetallic conduit, electrical metallic tubing, or *cable armor*.

(E)

The bonding jumper for a grounding electrode conductor* raceway or cable armor* shall be the same size as, or larger than, the enclosed grounding electrode conductor. Where a raceway is used as protection for a grounding electrode conductor, the installation shall comply with the requirements of the appropriate raceway article.

Cable armor is not a raceway nor is it armored cable.  It is an armored bare conductor made for pulling.  I really should go by H/D and check the labels.  It comes in a roll.  Other than the requirement to bond every end to the GEC and secure it, all that's left is the listing, if there is one.


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## Dennis (Feb 22, 2012)

Gregg Harris said:
			
		

> Galvin Electrical "The clamps are used to connect armored cable to water pipe for grounding."UL and CSA listed


Thank you-- I have never bonded with armored cable and it does not look like an armored cable connection.  It looks like a nm cable type of clamp and generally they are not compliant for flex.  I see that they are compliant.


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## chris kennedy (Feb 23, 2012)

ICE said:
			
		

> What do you west coast electricians do?  (I don't think they do it this way back east.)


Typical east coast install done yesterday.


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## Dennis (Feb 23, 2012)

chris kennedy said:
			
		

> Typical east coast install done yesterday.


Maybe in Florida but not here.  I have never seen a rod and gec installed like that.  I assume you guys have to use copper because of the salt down there?  I know I did when I did a house at the coast here in NC.  PVC wasn't allowed outdoors there because of the sun.  I installed a temp. pole with a pvc riser and I had to change it to galvinized.


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## ICE (Feb 23, 2012)

chris kennedy said:
			
		

> Typical east coast install done yesterday.


Is there a reason that you use insulated as opposed to a bare conductor?  Why are there two GEC?  Is that schedule 80 conduit?  What is the green bonding jumper for?  And I see an armored cable, what's that for?


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## chris kennedy (Feb 23, 2012)

ICE said:
			
		

> Is there a reason that you use insulated as opposed to a bare conductor?


Had it at the shop in the recycled wire rack.



> Why are there two GEC?


One comes from a 600A MDP and the other is a jumper to 2nd rod.



> Is that schedule 80 conduit?


40.



> What is the green bonding jumper for?


Goes to phone board.



> And I see an armored cable, what's that for?


Temp for construction.


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## chris kennedy (Feb 23, 2012)

Dennis said:
			
		

> I assume you guys have to use copper because of the salt down there?


Two 10'×¾" Cu rods is pretty much a boiler-plate spec on commercial jobs around here.



> PVC wasn't allowed outdoors there because of the sun.  I installed a temp. pole with a pvc riser and I had to change it to galvinized.


No PVC outdoors??? Tell me that a local amendment.


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## ICE (Feb 23, 2012)

Deleted by Tigerloose


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## Dennis (Feb 24, 2012)

chris kennedy said:
			
		

> No PVC outdoors??? Tell me that a local amendment.


Well it was 25 years ago for the temp. pole so I assume that it was for anything.  They said the sun at the beach was so intense the pvc would not last.  This was in Pawley's Island, SC.  The house I did was beachfront so not sure if that had anything to do with it.  It was the Power company that made me change it.


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## Dennis (Feb 24, 2012)

It is amazing how long I installed green tape on the insulated GEC wire not knowing it is not required.  My guys still tape it for some reason.  Old habits


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## ICE (Feb 25, 2012)

A co-worker viewed the picture and wondered why there was no green tape.


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## chris kennedy (Feb 25, 2012)

Dennis said:
			
		

> My guys still tape it for some reason.


Because you get your green tape for free???


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