different size grounds-solar

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Klockopotomis

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So i just did a service change for a solar contractor and I used #4 Cu for the ground rods and also for the water pipe ground. Solar guy is telling me I need #6 for the water bond and #4 to the ground rods.
This doesn't make any sense to me. I have it sized correctly according to incoming feeder size. But an equipotential plane has to exist in the grounding system. All wires have to be the same size to there is an equalizing. Am i missing something?
 
Klockopotomis said:
So i just did a service change for a solar contractor and I used #4 Cu for the ground rods and also for the water pipe ground. Solar guy is telling me I need #6 for the water bond and #4 to the ground rods.
This doesn't make any sense to me. I have it sized correctly according to incoming feeder size. But an equipotential plane has to exist in the grounding system. All wires have to be the same size to there is an equalizing. Am i missing something?
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Yes. You are missing all the BS that gets spread at the supply house while waiting for your order to be picked (second time today I used that one):lol:. The solar guy is talking nonsense and thas the sizes backwards (for a typical 200 amp service).
 
Klockopotomis said:
So i just did a service change for a solar contractor and I used #4 Cu for the ground rods and also for the water pipe ground. Solar guy is telling me I need #6 for the water bond and #4 to the ground rods.
This doesn't make any sense to me. I have it sized correctly according to incoming feeder size. But an equipotential plane has to exist in the grounding system. All wires have to be the same size to there is an equalizing. Am i missing something?
Click to expand...

How would wire size affect the creation of an equi-potential plane? As long as you meet the minimums, who cares if you up-size one conductor or the other?
 
im sorry yes i quoted him wrong the first time. Solar guy says #6 for ground rods and #4 for cold water. Last year I failed a service change because I did just that, inspector said all system grounds had to be the same size so that one ground did not have less resistance than another, an equipotential plane.
I have never come across it in the code book before tho
 
Klockopotomis said:
im sorry yes i quoted him wrong the first time. Solar guy says #6 for ground rods and #4 for cold water. Last year I failed a service change because I did just that, inspector said all system grounds had to be the same size so that one ground did not have less resistance than another, an equipotential plane.
I have never come across it in the code book before tho
Click to expand...

Alas, the "equal" in "equipotential" does not refer to the resistance of the conductors to the electrodes - thats not what we are trying to make "equal"
 
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