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Discussion Starter · #1 ·
An inspector asked for a second ground rod, I said I have measured the impedance and it was less than 25 Ohm, but he insisted on it, so there goes the second rod. Trouble is my ground wire (#6 solid) now is not going to be continuous, as it goes through the first rod and gets bonded to the nearby water line. It is inside a bonded EMT conduit and I have had hard enough time putting it there to begin even thinking of yanking it out and putting a longer one in.
How can I legitimately connect the second rod to the first one? Can I braze or weld or just use a second clamp on the first rod? The code we are going by here is NEC 2005.
 

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Second clamp. Generally I run a continuous wire from service to 1st rod, through the clamp, then to 2nd rod (All 1 piece) but the jumper between the 2 rods can be connected separately.

I have never heard of an inspector allowing 1 rod only without actually witnessing the test. We install 2 and go.
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Thank you.
Any chance of pointing to a reference in the code book to prove that it is legit?
Gonna make we work on a friday night?!? :no:

Well, OK, let me take a quick look.

Out of curiosity, do most inspectors in your area accept 1 rod with a test they don't witness? I don't think anyone around here even bothers testing.
 

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250.70 250.64(F)

The connection between the rods counts as a bonding jumper, I believe. The GEC (grounding electrode conductor) is from the service to the 1st electrode. (250.53(C))
 

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An inspector asked for a second ground rod, I said I have measured the impedance and it was less than 25 Ohm, but he insisted on it, so there goes the second rod. Trouble is my ground wire (#6 solid) now is not going to be continuous, as it goes through the first rod and gets bonded to the nearby water line.
How did you measure this resistance? Unless you used to proper tester (NOT a simple meter set to ohms) the inspector has a valid point.

What you are installing is a bonding jumper, NOT a GEC. Just add another clamp on the existing rod.

Here is a great Mike Holt graphic:
 

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What you are installing is a bonding jumper, NOT a GEC. Just add another clamp on the existing rod.
Hi Speedy Petey,

Good Holt graphics, but the PO also continues the 6awg through the Rod clamp to the water pipe electrode that really constitutes a GEC connection done in a unique way. That is what the PO is having trouble understanding. The bond jumper is of course the answer to finish the second rod installation that you have posted.

Sharkmobil,

Usually in residential, the Ground Electrode Conductor is required to connect to the water pipe electrode within 5 feet of its foundation exit. A second unspliced GEC bonds the UFER electrode or a supplemental 2 rods or plate etc per 250.52(A)(1 thru 7 if present). A UFER is the easiest method and saves the contracter $$$ not needing extra rods even when a plastic water supply is used. :thumbsup: rbj
 

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Hi Speedy Petey,

Good Holt graphics, but the PO also continues the 6awg through the Rod clamp to the water pipe electrode that really constitutes a GEC connection done in a unique way. That is what the PO is having trouble understanding. The bond jumper is of course the answer to finish the second rod installation that you have posted.
Nothing unique about it. The rods are allowed to be connected to any point in the grounding electrode system. The water pipe is one such point. It is not uncommon to have a single conductor bond building steel, then at another location tap steel to hit the water, and the water to a rod.

InPhase277
 

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Nothing unique about it. The rods are allowed to be connected to any point in the grounding electrode system. The water pipe is one such point. It is not uncommon to have a single conductor bond building steel, then at another location tap steel to hit the water, and the water to a rod.

InPhase277
Yer right in com'l or ind'l, but in residential, generally the UFER or Pipe is in opposite directions from the box. Someones spending too much time and copper to do it the other way, especially when the plumber hasn't come on the job yet.
 

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Discussion Starter · #17 ·
Those are just multi thousand dollar ohmmeters with sugar on top. As far as a procedure goes, I knew there had to be another rod inserted 8-10'' to truly measure the path to the ground, thats why I was not arguing too much against the second rod.
 

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I used an ohmmeter.
I'd have made you drive 4-10 footers if I was him. Ground testing requires the correct test equipment and additionally some training and expierence in utilizing this equipment.

I own 6 different earth ground resistance testers cost range between $1,200.00 and $4,500.00, the procedure for the three point test requires (for accurate results)a minimum of 33 test rods to be driven. Generally at 1', 10' 20' 30', 40', 50, 60', 66', 70', 80' 90' and one at 100' this is for a 10' rod. For larger ground electrodes the distance increases at 10 times the diagonal. This test, like most test requires proper training and a understanding of the work involved.
 
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