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#95537 - 09/20/05 07:40 AM Additional Ground Rod
George Little Offline
Member

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
When adding a grounding electrode to reach <25? when using a rod, is it permissible to for example, install a second acorn type clamp on the first rod and then run a piece of #6 copper to the second rod located at least 6 feet away from the first rod? The alternative would be to use only one clamp on the first rod and run through the clamp (uncut) to the second rod.
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George Little

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#95538 - 09/20/05 09:52 AM Re: Additional Ground Rod
Ryan_J Offline
Moderator

Registered: 08/19/03
Posts: 1355
Loc: West Jordan, Utah, USA
Yes, it is permitted.
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Ryan Jackson,
Salt Lake City

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#95539 - 09/20/05 10:25 AM Re: Additional Ground Rod
Bob Offline
Member

Registered: 02/05/02
Posts: 182
Loc: Mobile, AL, USA
Ryan
I thought the GEC had to be without splices except for specified connectors. I don't the the acron clamp was one of these clamps.

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#95540 - 09/20/05 10:40 AM Re: Additional Ground Rod
markp Offline
Member

Registered: 04/12/04
Posts: 60
Loc: Kent, WA, USA
The GEC is the conductor from the Service Neutral to the Ground Electrode System (GES). The GES consists of all the various electrodes which are bonded together. At any one electrode is where the GEC stops. Past this, they are electrode bonding conductors and I don't see any splicing prohibitions on those.

The only thing you have to watch is when different size bonding wires are used. Lets say you have a #4 to a water pipe and then a #6 from there to two rods. You can't run a #4 GEC from the service to the rod because the bonding wire to the pipe is too small. Running a #4 GEC to the water pipe would be OK. Running a #4 GEC to the first rod would be OK as long as a #4 connects the first rod to the pipe. Even if there was a #6 from the first rod to the second this would still be OK.
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Kent, WA

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#95541 - 09/20/05 05:28 PM Re: Additional Ground Rod
HotLine1 Offline


Member

Registered: 04/03/02
Posts: 6832
Loc: Brick, NJ USA
George:
The issue around here was that second #6 was put under the acorn. It is listed for a single conductor only.

Mark:
I have never came accross an installation, as you described. It reads like you are running a #4 from the panel to the water pipe, and then a #6 to the ground rods????
I have never seen that, now I'll have to go get the bible!! WHAT DO YOU GUYS THINK??

John
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#95542 - 09/20/05 05:31 PM Re: Additional Ground Rod
renosteinke Offline
Cat Servant
Member

Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
I have had to do something similar several times. Since we are locally required to enclose the GEC in pipe, and the pipe/ ground rod connector does not allow for the wire to continue elsewhere, it is necessary to use an additional pipe/rod clamp, and run a separate pipe, with a separate wire, to the next ground rod.

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#95543 - 09/20/05 08:06 PM Re: Additional Ground Rod
dmattox Offline
Member

Registered: 10/20/04
Posts: 267
Loc: Anaheim, CA
Quote:

The issue around here was that second #6 was put under the acorn. It is listed for a single conductor only.


Simply put 2 acorns on the first ground rod and you are good to go.

250.62(F) is a powerful section that it seems like few people come to grips with. The handbook has a picture that clearly shows the ramifications of it.

Quote:
To Electrode(s). A grounding electrode conductor shall be permitted to be run to any convenient grounding electode available in the grounding electrode system or to one or more grounding electrodes individually.


This allows both installations that George asks for, provided you use two connectors for the seperated GEC.

A little tip that this section allows is great for a large building. Say you have your switchgear near a building steel column. However your cold water is 500' across the warehouse which happens to be next to another building steel column. Simply bond your switch gear to the first column and bond the 2nd column to the cold water. Thus saving 500' of GEC.

One catch, engineers will often exceed NEC requirements and require seperate conductors. But, that is not required per the NEC.

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#95544 - 09/21/05 02:55 AM Re: Additional Ground Rod
iwire Offline
Moderator

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
Morning John

Quote:

I have never came accross an installation, as you described. It reads like you are running a #4 from the panel to the water pipe, and then a #6 to the ground rods????
I have never seen that, now I'll have to go get the bible!! WHAT DO YOU GUYS THINK??


I think it is fine.

I have gone from a large service to building steel then 200' - 250' across the building I jumped from building steel to water service saving the long run of 3/0 between the water line and the service.

Here is a Handbook image that shows some possibilities.



Bob
_________________________
Bob Badger
Construction & Maintenance Electrician
Massachusetts

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#95545 - 09/21/05 08:47 AM Re: Additional Ground Rod
gfretwell Offline


Member

Registered: 07/20/04
Posts: 9065
Loc: Estero,Fl,usa
OK how about if the electrode in question is a Ufer. I pick it up at the service disconnect and 300' away I find another piece of turned up Rebar, can I bond my water to that?
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Greg Fretwell

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#95546 - 09/21/05 10:38 AM Re: Additional Ground Rod
mxslick Offline
Member

Registered: 10/24/04
Posts: 785
Loc: Atomic City, ID USA
Based on the discussion and the image above, if the turned up rebar is closest to the water, I don't see any reason not to use it.

If any portion of the water is nearer to the service, then AHJ would probably say no.
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Stupid should be painful.

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