# Main Panel Bonding Etc.



## redlantern901 (Dec 19, 2012)

Hi guys, I'm an apprentice and my co-worker who is "teaching me" doesn't really answer my questions or ever refer to the code etc.. So I have a few questions.

Main Panel New Construction Romex (NM): I asked, if we are separating the equip grounds and neutrals by installing an equip ground buss which is bonded to the panel using the bond screw then are we required to install a bonding jumper for the neutral buss because I thought the reason reason we are bonding the neutral buss is because we are landing our equip grounds and our branch circuit neutrals on the same buss. He said "I don't know but I always bond both even when I separate them" Thanks for help and please reference code if needed.


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## erics37 (May 7, 2009)

He doesn't know what he's doing.

In a service, typically the neutral gets bonded exactly ONCE, usually at the Service Disconnecting Means. Everywhere on the load side of that enclosure, the neutrals and grounds will be separate. So, feeders, branch circuits, sub-panels, whatever - anything downstream will have an indepent equipment grounding conductor and a neutral isolated from non-current carrying metal.

Often times, like in a house or a small commercial facility, there is only one panel and it contains the service disconnect. In that case, if it's just a regular load center, there is already a main bonding jumper connecting the neutral & ground bus bars together. If there is a service disconnect upstream from there, for instance in a meter main, then the panel's factory MBJ needs to be removed and the neutral isolated from the enclosure.


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## redlantern901 (Dec 19, 2012)

erics37 said:


> He doesn't know what he's doing.
> 
> In a service, typically the neutral gets bonded exactly ONCE, usually at the Service Disconnecting Means. Everywhere on the load side of that enclosure, the neutrals and grounds will be separate. So, feeders, branch circuits, sub-panels, whatever - anything downstream will have an independent equipment grounding conductor and a neutral isolated from non-current carrying metal.
> 
> Often times, like in a house or a small commercial facility, there is only one panel and it contains the service disconnect. In that case, if it's just a regular load center, there is already a main bonding jumper connecting the neutral & ground bus bars together. If there is a service disconnect upstream from there, for instance in a meter main, then the panel's factory MBJ needs to be removed and the neutral isolated from the enclosure.


Thank you for answering and it's becoming clearer and I knew something was wrong because I am also attending night school to meet my educational requirements to further progress and get my license. It was a red flag to me he didn't know the answer and he is licensed. I do not want to jeopardize anyone's safety and I want to make sure everything I do will be code compliant and so I can teach others in the future. 

I do have some additional questions. To clarify, the service disconnect is the panel with the main breaker in it such as a 100A double pole main not a meter that can be pulled from it's socket correct? Though I know some meters have breakers in them and a disconnect lever etc..In this scenario the neutral is bonded to the meter can, but is it also bonded in the main panel even though we are separating the neutral and ground buss? The reason I ask because he doesn't know the answer or maybe he's just doesn't want to explain but also it's a GE 40CKT panel and to keep it clean what he does is leave the neutral strap attached in the load center, installs the bonding screw and lands his neutrals to the left and right of the panel based on the way the cables are coming in, in addition to that he installs an equip ground bus which is also bonded with a bond screw where he lands all the bare or green wires.


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## ElectricJoeNJ (Feb 24, 2011)

redlantern901 said:


> Thank you for answering and it's becoming clearer and I knew something was wrong because I am also attending night school to meet my educational requirements to further progress and get my license. It was a red flag to me he didn't know the answer and he is licensed. I do not want to jeopardize anyone's safety and I want to make sure everything I do will be code compliant and so I can teach others in the future.
> 
> I do have some additional questions. To clarify, the service disconnect is the panel with the main breaker in it such as a 100A double pole main not a meter that can be pulled from it's socket correct? Though I know some meters have breakers in them and a disconnect lever etc..In this scenario the neutral is bonded to the meter can, but is it also bonded in the main panel even though we are separating the neutral and ground buss? The reason I ask because he doesn't know the answer or maybe he's just doesn't want to explain but also it's a GE 40CKT panel and to keep it clean what he does is leave the neutral strap attached in the load center, installs the bonding screw and lands his neutrals to the left and right of the panel based on the way the cables are coming in, in addition to that he installs an equip ground bus which is also bonded with a bond screw where he lands all the bare or green wires.


A meter itself is not a disconnecting means, and that lever you mention is a bypass lever. Now, the way he is wiring that panel is 100% correct. It's a main breaker panel so the neutral and ground are bonded. That strap actually connects both left and right side neutral bars. It can be removed in subpanel applications for easier wiring. One thing he dosent have to do is install the seperate ground bar, that's pure preference and could be needed for more space. As long as that bond screw is in everything's good. One thing I like to do is install a jumper when I use extra ground bars, I don't like to rely on the can for the connection.


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## redlantern901 (Dec 19, 2012)

ElectricJoeNJ said:


> A meter itself is not a disconnecting means, and that lever you mention is a bypass lever. Now, the way he is wiring that panel is 100% correct. It's a main breaker panel so the neutral and ground are bonded. That strap actually connects both left and right side neutral bars. It can be removed in subpanel applications for easier wiring. One thing he dosent have to do is install the seperate ground bar, that's pure preference and could be needed for more space. As long as that bond screw is in everything's good. One thing I like to do is install a jumper when I use extra ground bars, I don't like to rely on the can for the connection.


Exactly the answer I was looking for. Thanks! I think Eric thought the panel was been used as a sub but maybe I didn't explain it well enough but I understand the neutral is insulated and the equip grounds are separate in sub panel applications. Running a jumper is a great idea and I will definitely do that from now on since it can't hurt. Thank you again for your help.


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