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Posted By: triple grounding electrode conductor - 01/03/07 03:39 AM
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.
Posted By: renosteinke Re: grounding electrode conductor - 01/03/07 03:52 AM
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.
Posted By: triple Re: grounding electrode conductor - 01/03/07 10:28 PM
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.
Posted By: iwire Re: grounding electrode conductor - 01/03/07 10:47 PM
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.

[Linked Image]
Posted By: Ryan_J Re: grounding electrode conductor - 01/04/07 01:36 PM
Jon, the second rod would be supplemental, not supplementary.
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