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#205438 - 02/21/12 08:13 AM 250.64(F)(3)??
Up2code Offline
Member

Registered: 05/15/07
Posts: 55
Loc: Missouri
Can this 1/4" x 2" copper or aluminum busbar, this section is referring to, be an equipment grounding conductor terminal busbar in a subpanel?

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#205448 - 02/22/12 08:38 AM Re: 250.64(F)(3)?? [Re: Up2code]
Niko Offline
Member

Registered: 08/17/06
Posts: 358
Loc: Campbell, CA
So you are saying that you have a 1/4" x 2" bar in the subpanel that you want to use? OR instead of 1/4" x 2" you want to use the grounding busbar in the subpanel?
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#205449 - 02/22/12 10:06 AM Re: 250.64(F)(3)?? [Re: Up2code]
Up2code Offline
Member

Registered: 05/15/07
Posts: 55
Loc: Missouri
Correct. Could the grounding busbar in the subpanel be used for this purpose, since it meets the requirements such as being aluminum or copper AND 1/4" by 2" minimum.

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#205450 - 02/22/12 10:34 AM Re: 250.64(F)(3)?? [Re: Up2code]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
I am still not sure I understand the situation. Why would the GEC be going to a sub panel?
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#205451 - 02/22/12 11:00 AM Re: 250.64(F)(3)?? [Re: Up2code]
Up2code Offline
Member

Registered: 05/15/07
Posts: 55
Loc: Missouri
New main service panelboard with disconnect, was installed in building, which the Grounding Electrode Conductors were terminated in(NEC 2008 250.64(F)(2).

NOW... POCO wants the main service disconnect OUTSIDE the building, per their preference.

Well... doing so would make the indoor, newly installed main service panelboard, with disconnect now a feeder panel. Which will now require removal of MBJ and installation of a seperate equipment grounding conductor from newly required OUTDOOR service disconnect.

QUESTION is now what should be done with the Grounding Electrode Conductors(which now are just bonding jumpers to the different electrodes) that are terminated in what is now the feeder panel.

If a new, Grounding Electrode Conductor were installed from the newly required, outdoor service disconnect...

into what is now the feeder panel....

and terminated on the equipment grounding conductor terminal bar...

would that be in compliance with NEC 2008 250.64(F)(3)?

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#205452 - 02/22/12 12:38 PM Re: 250.64(F)(3)?? [Re: Up2code]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
I would not want to see that setup at all. I would want a legal splice in the GEC going right to the service disconnect or some other place between there and the service point.

You could get that 1/4"x 2" bonding bus and be legal. (although the examples of this bonding bus in the handbook refer to multiple SDSs)

Easier would be to just run a new GEC to the service panel if you have an accessible electrode like building steel or a water pipe and bond the other electrodes there.



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#205453 - 02/22/12 12:50 PM Re: 250.64(F)(3)?? [Re: Up2code]
Niko Offline
Member

Registered: 08/17/06
Posts: 358
Loc: Campbell, CA
Originally Posted By: Up2code
Correct. Could the grounding busbar in the subpanel be used for this purpose, since it meets the requirements such as being aluminum or copper AND 1/4" by 2" minimum.


the minimum requirement per NEC is 1/4" thick by 2" wide. the grounding bar in the subpanel is not 2" wide.

If you can, just install a bar outside of the panel and connect all of your existing GEC to it.
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#205454 - 02/22/12 12:55 PM Re: 250.64(F)(3)?? [Re: gfretwell]
Up2code Offline
Member

Registered: 05/15/07
Posts: 55
Loc: Missouri
Yes, I understand running a new GEC to an independent splice point or external bonding point, for the electrode bonding jumpers, would be the preferred method.

Issue at hand, though, is whether or not using the subpanel grounding terminal bar as this 1/4" x 2" bar is a violation or not.

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#205456 - 02/22/12 02:36 PM Re: 250.64(F)(3)?? [Re: Up2code]
HotLine1 Offline

Member

Registered: 04/03/02
Posts: 6785
Loc: Brick, NJ USA
"Issue at hand, though, is whether or not using the subpanel grounding terminal bar as this 1/4" x 2" bar is a violation or not."

Is this bar in fact 1/4" thick, and 2" wide, and xx" long?

Ground blocks/bars are usually not 1/4" thick, 2" wide by xx" long.

I have to agree with Gregs first paragraph, in his response above.
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#205457 - 02/22/12 03:24 PM Re: 250.64(F)(3)?? [Re: Up2code]
Up2code Offline
Member

Registered: 05/15/07
Posts: 55
Loc: Missouri
Niko, I have seen grounding bars that are 1/4" thick by 2" wide, in some bigger switch gear equip. So then that would not be a violation correct?

But the grounding terminal bar that is not 1/4" thick by 2" wide, in similiar gear or subpanels, would obviously be a violation?

Both those statements sound correct?

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