Service Panel: neutral and grounding conductors terminate on a single bus bar.

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I write a library of narratives that I sell as custom templates for various home inspection software so I have to be careful that what I say is correct. I don't consider this condition a defect but some inspectors will include it because a client might question it. Think this is acceptable:

"In the service panel, equipment grounding and neutral conductors terminated on a single bus bar. While not specifically approved by the panel manufacturer or the National Electric Code (NEC), the grounding and neutral bus bars are required to be electrically connected in the service panel. This configuration serves that purpose without creating a defective condition."
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
I write a library of narratives that I sell as custom templates for various home inspection software so I have to be careful that what I say is correct. I don't consider this condition a defect but some inspectors will include it because a client might question it. Think this is acceptable:

"In the service panel, equipment grounding and neutral conductors terminated on a single bus bar. While not specifically approved by the panel manufacturer or the National Electric Code (NEC), the grounding and neutral bus bars are required to be electrically connected in the service panel. This configuration serves that purpose without creating a defective condition."
Remember, the NEC is permissive, unless it states otherwise, it is permitted. So, yes the EG & neutral are allowed on the same busbar at the Service Entrance. They may also be separated.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Here is the article

200.2 General. Grounded conductors shall comply with
200.2(A) and (B).
(A) Insulation. The grounded conductor, if insulated, shall
have insulation that is (1) suitable, other than color, for any
ungrounded conductor of the same circuit for systems of
1000 volts or less, or impedance grounded neutral systems of
over 1000 volts, or (2) rated not less than 600 volts for solidly
grounded neutral systems of over 1000 volts as described in
250.184(A).
(B) Continuity. The continuity of a grounded conductor shall
not depend on a connection to a metallic enclosure, raceway,
or cable armor.
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
So, yes the EG & neutral are allowed on the same busbar at the Service Entrance.

And also make note that while the neutral and ground conductors can share the same bus bar, they can not share the same hole/lug position. Each neutral conductor needs to be in its own hole, while (2) ground conductors can often be installed together.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
I write a library of narratives that I sell as custom templates for various home inspection software so I have to be careful that what I say is correct. I don't consider this condition a defect but some inspectors will include it because a client might question it. Think this is acceptable:

"In the service panel, equipment grounding and neutral conductors terminated on a single bus bar. While not specifically approved by the panel manufacturer or the National Electric Code (NEC), the grounding and neutral bus bars are required to be electrically connected in the service panel. This configuration serves that purpose without creating a defective condition."
I'm not sure that I like the bold part because in the first part you state that there is a single bus bar then you go on to say that the grounding and neutral bus bars are required to be connected. It's confusing to state that you have one bar but then comment that there are two that are required to be connected together. Also why would an HI call out a single bus bar with both EGC's and neutrals connected to when it's a very standard practice and it's code compliant?
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
If the ground bar is separate from the neutral bar and is only connected thru the panel casing then you cannot use the equipment grounding bar for the neutrals. If the neutral bar and equipment grounding bar are attached by wire or a buss then it is not an issue.
Say you encountered the situation in the first sentence, and want to remedy it via adding a jumper wire between the ground bar and the neutral bar in the service panel, as suggested in the second sentence. How would you size that wire? If based on the ratings of the circuits whose neutrals land on the ground bar, is 200.4(A) an issue?

Cheers, Wayne
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I am not sure there is a way to be compliant but if I had to do it I would base the jumper on the neutral load that I would be adding to the bar.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
What if the bar only had holes for #4, tops, in a 200 amp panel?


I think you know the answer. Either find another way or get those lugs that go under 2 screws.

32FV95_AS01
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
IMO, this is a bit of a gray area but I would make sure all my heavy loads were in the main neutral bar if possible.
 
And also make note that while the neutral and ground conductors can share the same bus bar, they can not share the same hole/lug position. Each neutral conductor needs to be in its own hole, while (2) ground conductors can often be installed together.
Just a few days I had an Eaton BR ground bar and actually read the destructions. To my surprise, It allowed 3 14s or 12s in each hole. Same size, material and stranding required.
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
Just a few days I had an Eaton BR ground bar and actually read the destructions. To my surprise, It allowed 3 14s or 12s in each hole. Same size, material and stranding required.
Seems like the bars are adequately sized for the most part nowadays but we rarely use panels that allow half sized breakers.
I can remember pigtailing multiple EGs to find a hole in the older loadcenters prior to their increased width. PIA even with young eyes, steady hands, and MWBCs.
 

kwired

Electron manager
Location
NE Nebraska
Just a few days I had an Eaton BR ground bar and actually read the destructions. To my surprise, It allowed 3 14s or 12s in each hole. Same size, material and stranding required.
In early 90's place I worked installed mostly CH panels. I recall noticing their neutral and ground bars back then allowed three conductors per terminal, of course needed to be EGC's and not neutral conductors, though back then that was per instructions and not direct code rule and many times there were multiple neutrals installed in one hole. We usually installed neutral and EGC of the same circuit in same hole until NEC pointed out that isn't what is intended.
 

DBoone

Senior Member
Location
Mississippi
Occupation
General Contractor
In early 90's place I worked installed mostly CH panels. I recall noticing their neutral and ground bars back then allowed three conductors per terminal, of course needed to be EGC's and not neutral conductors, though back then that was per instructions and not direct code rule and many times there were multiple neutrals installed in one hole. We usually installed neutral and EGC of the same circuit in same hole until NEC pointed out that isn't what is intended.

Seen that a good bit. Must have been pretty common.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
"In the service panel, equipment grounding and neutral conductors terminated on a single bus bar. While not specifically approved by the panel manufacturer or the National Electric Code (NEC), The grounding and neutral bus bars are required to be electrically connected in the service panel. This configuration serves that purpose without creating a defective condition. If the ground bar is separate from the neutral bar and is only connected thru the panel casing, then you cannot use the equipment grounding bar for the neutrals. "

Striking out the unnecessary part of your language, and adding part of Dennis' post #3, produces a good result in my opinion. The "while not specifically approved" is unnecessary because it isn't specifically disapproved either.
 
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I write a library of narratives that I sell as custom templates for various home inspection software so I have to be careful that what I say is correct. I don't consider this condition a defect but some inspectors will include it because a client might question it. Think this is acceptable:

" In the service panel, equipment grounding and neutral conductors terminated on a single bus bar. While not specifically approved by the panel manufacturer or the National Electric Code (NEC), the grounding and neutral bus bars are required to be electrically connected in the service panel. This configuration serves that purpose without creating a defective condition."

Regarding the part in red: First, there is a typo there. Is there an "are" missing, or is it supposed to be "terminate"?

So regardless of that little nit pick, I still don't like the part in red. Perhaps it would be better to say "it is common....". Note that the code language implies there Is a separate N and G bar, and they are connected together with an MBJ (for a grounded system).

Regarding the part in blue, the two bars ARE required by the NEC to be electrically connected..

I would start over from scratch. I'm not trying to mean, it's just wrong, confusing, and sloppy.
 
I'm not sure that I like the bold part because in the first part you state that there is a single bus bar then you go on to say that the grounding and neutral bus bars are required to be connected. It's confusing to state that you have one bar but then comment that there are two that are required to be connected together. Also why would an HI call out a single bus bar with both EGC's and neutrals connected to when it's a very standard practice and it's code compliant?
The only reason would be because it's different and might be asked about. But the majority of inspectors who have responded on other forums thought that it was better left unmentioned.
 
Regarding the part in red: First, there is a typo there. Is there an "are" missing, or is it supposed to be "terminate"?

So regardless of that little nit pick, I still don't like the part in red. Perhaps it would be better to say "it is common....". Note that the code language implies there Is a separate N and G bar, and they are connected together with an MBJ (for a grounded system).

Regarding the part in blue, the two bars ARE required by the NEC to be electrically connected..

I would start over from scratch. I'm not trying to mean, it's just wrong, confusing, and sloppy.
I don't take suggestions personally, I appreciate them. I'm here trying to keep home inspectors out of court and if I'm wrong I want to know it.

We use past tense in our reports. A home inspection is supposed to be like a snapshot in time, so as soon as we leave the home, the report is a description of the house as it was in the past.

Also yes, I agree, the first part of the second sentence is bad. It's supposed to refer to conditions in the first sentence and if it's to be included at all, it should be in the first sentence. Rewritten, basically.

Thanks guys, this site is a wealth of information! On some of the home inspection message boards and Facebook groups there can be a lot of conflicting opinions and squabbling to deal with!
 
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