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#100787 - 01/02/07 07:39 PM grounding electrode conductor
triple Offline
Member
Registered: 04/01/02
Posts: 184
Loc: Wisconsin
250.56 and 250.64(F):
If 25 ohms or less is not achieved with one ground rod, and a second one is added, do the two need to be tied together with the same continuous wire back to the common bonding point (panel)? I realize that an irreversible connection could be used but is there any reason that a separate wire couldn't be run from each of the two rods back to the panel? BTW, Wisconsin requires two ground rods no matter what.
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#100788 - 01/02/07 07:52 PM Re: grounding electrode conductor
renosteinke Offline
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Registered: 01/22/05
Posts: 5316
Loc: Blue Collar Country
The first rod is your "grounding electrode." The second is a "supplementary electrode" It can be attached with a separate wire to the first rod.
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#100789 - 01/03/07 02:28 PM Re: grounding electrode conductor
triple Offline
Member
Registered: 04/01/02
Posts: 184
Loc: Wisconsin
If the first electrode does not meet the 25 ohm maximum requirement then the second electrode is not simply a "supplementary grounding electrode" is it? Also, since Wisconsin requires two in every case then the second one would never be supplimental (imo). Renosteinke, are you suggesting that the wire from the second rod can be simply bolted to the first rod without an irreversible connection to the first rod's conductor? How about 250.64(C)?

Thank you.
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#100790 - 01/03/07 02:47 PM Re: grounding electrode conductor
iwire Offline
Moderator
Registered: 01/05/03
Posts: 4391
Loc: North Attleboro, MA USA
Triple, the conductor from one electrode to another is not a GEC.

The GEC runs from the panel to some point of the grounding electrode system.

The conductors that connect multiple grounding electrodes together are bonding jumpers. 250.64(C) does not apply to these bonding jumpers.

Here is a picture from the handbook showing different ways of connecting the grounding electrode system together.

_________________________
Bob Badger
Construction & Maintenance Electrician
Massachusetts
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#100791 - 01/04/07 05:36 AM Re: grounding electrode conductor
Ryan_J Offline
Moderator
Registered: 08/19/03
Posts: 1374
Loc: West Jordan, Utah, USA
Jon, the second rod would be supplemental, not supplementary.
_________________________
Ryan Jackson,
Salt Lake City
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