Ground rods

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jaggedben

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You need full-sized conductor between main disco and water pipe, only #6 cu between main and rods or between water pipe and rods.

I don't agree that's clear. Main GEC to the grounding electrode system is sized per 250.66. I think if it connects both rods, that's its size. Bonding jumper from the first to the second rod is not required to be more than #6. If you run separate GECs or bonding jumpers to each rod they are not required to be more than #6.
 

Dennis Alwon

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I don't agree that's clear. Main GEC to the grounding electrode system is sized per 250.66. I think if it connects both rods, that's its size. Bonding jumper from the first to the second rod is not required to be more than #6. If you run separate GECs or bonding jumpers to each rod they are not required to be more than #6.


Larry is saying if you run the grounding electrode conductor to the water pipe from the main panel than it needs a full sixe... 200 amp means #4-- and so on based on 250.66.

Correct the rods only need #6 but if you go to a water pipe from the rod and the water pipes need #4 then you need a #4 to the rod.
 

LarryFine

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I was using the example of service to water pipe (#4) then water pipe to rod 1 (#6) and rod 2 (#6).
 

hhsting

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Please see the attachment post #1. 3 sets of 500 kcmil Al is the incoming service conductor to the service disconnect.

Following is shown post #1 attachment:

A. From the service disconnect to the water pipe grounding electrode conductor is sized 3/0 cu or 4/0 Al.

B. From the water pipe to the ground rod bonding jumper is sized #6 cu or #4 Al.

C. Between ground rods #6 cu or #4 Al.

My question is B and C correct size?
 

jaggedben

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Solar and Energy Storage Installer
Please see the attachment post #1. Following is shown:

A. From the service disconnect to the water pipe grounding electrode conductor is sized 3/0 cu or 4/0 Al.

B. From the water pipe to the ground rod bonding jumper is sized #6 cu or #4 Al.

C. Between ground rods #6 cu or #4 Al.

My question is B and C correct size?

C is correct.

B arguably needs to be the same as A.
 

hhsting

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Why do you keep insisting on putting aluminum in there?

B and C are correct with #6 copper
Cool i wont put Al. Will put Cu. Was trying to let you all know what I have is bonding jumper not GEC. Rules pointed out apply to GEC. Dont see in code rules for bonding jumper that you all pointed out.

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hhsting

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Can anyone from here with experience in code please verify for certain post #24 part B bonding jumper size can be #6 awg copper per Nec 2014 Article 250.53(E) Or does bonding jumper size need to be same as part A?



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infinity

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Can anyone from here with experience in code please verify for certain post #24 part B bonding jumper size can be #6 awg copper per Nec 2014 Article 250.53(E) Or does bonding jumper size need to be same as part A?



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Didn't Dennis answer that in post #27?
 

jaggedben

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For B look at Nec 2014 250.53(E). Now is it correct?

Maybe not. That section refers to a single electrode only. Granted, both your rods are supplemental electrodes, but we are talking about a bonding jumper connecting two electrodes, not a 'bonding jumper that is the sole connection' to a single supplemental electrode. If your inspector says it has be to 3/0 because of the same logic, I don't think there's anything to say to that.

Most jurisdictions I work in don't enforce the full NEC requirements for the grounding electrode system, and in the one that particularly does I haven't come into a situation quite like this where it really mattered. Since we do almost all residential, we usually we just stock 4awg copper and that's good for everything. Continuing the #4 6ft over to the next ground rod is cheaper than adding another clamp or an irreversible splice. Continuing 3/0 from the water, I see how that could be a pain, but I just can't speak from experience on that.
 

roger

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Can anyone from here with experience in code please verify for certain post #24 part B bonding jumper size can be #6 awg copper per Nec 2014 Article 250.53(E) Or does bonding jumper size need to be same as part A?



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It was answered.

Roger
 

infinity

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Maybe not. That section refers to a single electrode only. Granted, both your rods are supplemental electrodes, but we are talking about a bonding jumper connecting two electrodes, not a 'bonding jumper that is the sole connection' to a single supplemental electrode. If your inspector says it has be to 3/0 because of the same logic, I don't think there's anything to say to that.

I would argue that in a two rod setup a single rod is not an electrode unless you can prove it's 25Ω or less. It only qualifies as an electrode when the two rods are somehow connected together.
 
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