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Sam Morris
01-10-2015, 09:51 AM
What's this bar on the very top of the GE electrical panel called and what's its purpose ? Does anyone see anything wrong with this service panel. When do you use the bonding screw? Thanks

Eric Barker
01-10-2015, 10:07 AM
What's this bar on the very top of the GE electrical panel called and what's its purpose ? Does anyone see anything wrong with this service panel. When do you use the bonding screw? Thanks
That bar bridges / bonds the left and right side neutral bus bars. A grounding screw is necessary when a main disconnect is present in the panel.

Jerry Peck
01-10-2015, 10:08 AM
As a service equipment panel, which I presume that is with that main disconnect installed, that bar bonds the neutral and ground terminal bars together, making both terminal bars serve as neutral/ground terminal bars.

When that bar is removed in a panel which is not service equipment, the neutral terminal bar (which has the neutral lug installed on it) becomes the neutral terminal bar and must be isolated from ground (any bonding screw or strap must be removed) - then the other bar becomes the ground terminal bar for the equipment grounds and that bar must have a bonding screw or strap which connects the ground terminal bar to the enclosure.

Most manufacturers which have those bars in their panels require (when the metal bar is removed) the metal bar be replaced with a plastic bar as the bar also helps support and hold the neutral and ground terminal bars in place. The requirement for the replacement plastic bar will be in the label where it shows that the bar may be removed - some do not require the bar be replaced with a non-conductive plastic bar, most do.

In you photo, the neutral is connected to the bottom of the left terminal bar, making that the neutral terminal bar if that crossover bar is removed. The right side terminal bar has the GEC (Grounding Electrode Conductor) connected to the ground terminal at the bottom of the right terminal bar. With the metal crossover bar in place, both terminal bars are neutral/ground terminal bars.

Jack Feldmann
01-10-2015, 02:40 PM
Sam,
You should come to our Chapter meeting in Knoxville in February. You will get some great continuing education, as well as meet several inspectors. Feel free to contact me for info. Its on Saturday 2/21/15. Generally runs from 7:30am tip about 1 or 2. I know we are having a 4 hour class with a structural engineer, for one session. There may be a brief session on another topic. We also have pretty good food for lunch.

Scott Cook
01-13-2015, 08:23 AM
Sam,

That is a factory installed Neutral Crossbar. The auxiliary ground bar would be installed directly on the back of the box, on the right or left side. While it is possible, and legal, to remove it and convert one side from a neutral bar to a ground bar with the addition of a bonding screw or strap, it might cause a problem with having enough neutral screws to install all the neutral wires, since each one is required to be installed under it's own screw. While this was always requirement under UL67, it was given it's own identity in the NEC in 2008 as 408.41 by a unanimous vote.

http://ecatalog.squared.com/pubs/Electrical%20Distribution/Panelboards/0100DB0705.pdf

The justification can be found at this link: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0CEQQFjAF&url=https%3A%2F%2Fwww.nachi.org%2Fforum%2Fattachme nts%2Ff19%2F46404d1310577490-neutral-and-ground-branch-wires-neutral-termination-requirement-nec-change-code-panel-log.pdf&ei=uDS1VOvWJcahNs6rgtgE&usg=AFQjCNH1vIHTudAz5ZKheHs8l0zmh3769w&sig2=ufAjLCsDmVuCeg9KjbAeyg

Jerry Peck
01-13-2015, 08:39 AM
Sam,

That is a factory installed Neutral Crossbar. The auxiliary ground bar would be installed directly on the back of the box, on the right or left side. While it is possible, and legal, to remove it and convert one side from a neutral bar to a ground bar with the addition of a bonding screw or strap, it might cause a problem with having enough neutral screws to install all the neutral wires, since each one is required to be installed under it's own screw. While this was always requirement under UL67, it was given it's own identity in the NEC in 2008 as 408.41 by a unanimous vote.

http://ecatalog.squared.com/pubs/Electrical%20Distribution/Panelboards/0100DB0705.pdf

The justification can be found at this link: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0CEQQFjAF&url=https%3A%2F%2Fwww.nachi.org%2Fforum%2Fattachme nts%2Ff19%2F46404d1310577490-neutral-and-ground-branch-wires-neutral-termination-requirement-nec-change-code-panel-log.pdf&ei=uDS1VOvWJcahNs6rgtgE&usg=AFQjCNH1vIHTudAz5ZKheHs8l0zmh3769w&sig2=ufAjLCsDmVuCeg9KjbAeyg

Sam,

http://apps.geindustrial.com/publibrary/checkout/DET-489?TNR=Application%20and%20Technical|DET-489|generic

"Removable crossbar to isolate neutral and ground bars"

There is absolutely nothing wrong with removing those crossover bars (crossbars), you will not end up short on neutral terminal bar holes when properly wired.

Removing that bar will not only not cause problems, that bar is designed, and intended, to be removed to allow separation of the neutral terminal side (which has the larger neutral lug on it) from the ground terminal side (which has the smaller lug on it).

Leaving the bar in place allows both sides to serve a both neutral and ground terminals, and the bonding screw/jumper would be required to bond the enclosure to the grounds.

When the bar is removed, the ground terminal bar (and only the ground terminal bar) is bonded to the enclosure.

Scott is correct in that only one neutral conductor is permitted per terminal, but that has been common knowledge for decades, and was addressed in the listing and labeling, the NEC was late to include it because the NEC requires installation per the listing and labeling ... apparently so many electricians did not read the listing and labeling and were installing more than one neutral per terminal.