# Multiple panel grounding



## waco (Dec 10, 2007)

Two, 200 amp residential panels, side by side. Both have GECs going to two ground rods, but only one has a ground going to the water pipe. Seems I recall that both panels have to have the primary (water pipe) ground and "daisy chaining" them (ground bar to ground bar to pipe) is a no-no.

Is my memory correct? Two grounds, one for each panel, going to the water pipe?


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## TOOL_5150 (Aug 27, 2007)

One water bond is sufficient

~Matt


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## RePhase277 (Feb 5, 2008)

Where do these panels get their power? I would take the ground rods and water bond to the service, not the panels.


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## Magnettica (Jan 23, 2007)

I'll go one step further and say they need to go to the main disconnect.

Are these (2) 200 amp panels Main Breaker panels?


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## gilbequick (Oct 6, 2007)

Are these panels a part of the same service?


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## waco (Dec 10, 2007)

Sorry I wasn't clear. These are both mains with disconnects, not subs, both fed from the meter socket.

Man, if only one water pipe ground is needed, then things are good!


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## Dennis Alwon (May 9, 2009)

waco said:


> Sorry I wasn't clear. These are both mains with disconnects, not subs, both fed from the meter socket.
> 
> Man, if only one water pipe ground is needed, then things are good!


So there is one meter-- 400 amp service? or 2 separate meters?


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## waco (Dec 10, 2007)

Dennis Alwon said:


> So there is one meter-- 400 amp service? or 2 separate meters?


Yes, 400 amp service. You're messing with me, aren't you?


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## Dennis Alwon (May 9, 2009)

waco said:


> Yes, 400 amp service. You're messing with me, aren't you?


No, not really but I actually don't know for sure since I always install my gec in the meter. I believe you need both but you can jump from one panel to the other rather than run 2 separate gec's to the water pipe.


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## waco (Dec 10, 2007)

Yes, I call that "daisy chaining" when going from one panel to the other then to the water pipe. Here, we don't run the GEC to the meter socket. It is my impression that it is a PUCO rule since they like to claim ownership of the meter sockets, but NEVER install them!


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## cmac1 (Aug 31, 2008)

isn't the neutral conductor already providing the link.


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## Dennis Alwon (May 9, 2009)

I think this answers the question



> 250.64 Grounding Electrode Conductor Installation.
> 
> (D) Service with Multiple Disconnecting Means Enclosures. Where a service consists of more than a single enclosure as permitted in 230.71(A), grounding electrode connections shall be made in accordance with (D)(1), (D)(2), or (D)(3).
> (1) Grounding Electrode Conductor Taps. Where the service is installed as permitted by 230.40, Exception No. 2, a common grounding electrode conductor and grounding electrode conductor taps shall be installed. The common grounding electrode conductor shall be sized in accordance with 250.66, based on the sum of the circular mil area of the largest ungrounded service-entrance conductor(s). Where the service-entrance conductors connect directly to a service drop or service lateral, the common grounding electrode conductor shall be sized in accordance with Table 250.66, Note 1. A tap conductor shall extend to the inside of each service disconnecting means enclosure. The grounding electrode conductor taps shall be sized in accordance with 250.66 for the largest conductor serving the individual enclosure. The tap conductors shall be connected to the common grounding electrode conductor by exothermic welding or with connectors listed as grounding and bonding equipment in such a manner that the common grounding electrode conductor remains without a splice or joint.
> ...


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## FREE MAN (Dec 10, 2020)

I'm dealing with the same issue with bidding a job. We have a 600 amp CT cabinet supplying three 200 amp panels. Trying to figure out if I have to run a GEC from each panel all the way to the water main or if I can daisy chain them through?


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## cuba_pete (Dec 8, 2011)

Dang, man...we've gone through...like...four code changes since this thread was last visited.

Which answer from the past do you want?


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## Switched (Dec 23, 2012)

cuba_pete said:


> Dang, man...we've gone through...like...four code changes since this thread was last visited.
> 
> Which answer from the past do you want?


The cheapest one!


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