Neutral Bar Bonding Question

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andrewdbis

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Location
New Jersey
I have a service panel with two neutral bus bars the left bar has an GEC and the service neutral but no panel bond screw. The right bar has another GEC and the panel bonding screw but no bond bar or jumper to the other neutral bus. This is a problem, correct?
 

infinity

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New Jersey
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Journeyman Electrician
Yes if there is no connection between the two bars that would be a problem. Do you have any photo's?
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
Although not rigidly enforced, 250.24 requires the grounding electrode conductor be connected to the buss with the grounded conductor and 250.24(B) seems to indicate the main bonding jumper be connected likewise.
In addition, the enclosure can not be used to carry neutral current.
Ideally your right hand bar would be for equipment grounding conductors only.
 

Little Bill

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Tennessee NEC:2017
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Although not rigidly enforced, 250.24 requires the grounding electrode conductor be connected to the buss with the grounded conductor and 250.24(B) seems to indicate the main bonding jumper be connected likewise.
In addition, the enclosure can not be used to carry neutral current.
Ideally your right hand bar would be for equipment grounding conductors only.
OP said the right bar had the bonding screw, wouldn't that be for the grounded conductors? I know he said the grounder service conductor landed on the left bar but, IMO, it should have landed on the right bar where the bonding screw is.
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
One way or the other.. As long as the neutral, grounding electrode & main bond jumper are on the same bar..right or left.
 

Dennis Alwon

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Chapel Hill, NC
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It is hard to tell if those bars are connected internally. If not connected then you have a non compliant situation
 

infinity

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Location
New Jersey
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There is definitely something wrong here with the neutral bar on the left. That pitted, rusty looking thing must have come from an old panel and is not connected to the one on the right.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
The left bus has the incoming neutral and a GED (big black wire, I believe), the right bus has the panel bond, they both have EGCs and neutrals.

They MUST be joined. If they aren't, join the two large top lugs.
 

andrewdbis

Member
Location
New Jersey
They must be connected if they aren't connected then the neutrals on the right side wouldn't work
I thought that too...but I didn't notice any circuits not working properly. I also thought they MUST be connected but the panels label only accounts for the right bus bar so the left was added after the fact.
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
There may be other reasons "it's working". If the equipment grounds happen to be connected on the "right" circuits the right bar could be getting a connection via the equipment grounds.
You could disconnect everything and check continuity between bars but it would be easier to just add a "jumper"
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
I looked closely at the enlargement on the host site. There is a bare GEC on the lower right bus, and the SE neutral and one large black wire on the left bus that does not go to the right bus. Every other terminal on the left but contains a white and a bare.

I would at least recommend placing a voltmeter between the two. If it's a constant zero, there must be a connection outside the panel between the bare GEC and the thick black wire. Even if so, there should be an inside jumper instead (to avoid parallel current).
 

Little Bill

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Location
Tennessee NEC:2017
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Semi-Retired Electrician
One way or the other.. As long as the neutral, grounding electrode & main bond jumper are on the same bar..right or left.
I didn't mean right or left as that's always the case. I was referring to the fact that his bonding screw was on the right side and that's where the grounded conductor should have been.
 
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