Grounding electrode conductor sizing

[markimhoff]

If the only electrodes that I am using for a service are two 5/8" x 8' ground rods then according to 250.66 (A) the grounding electrode conductor isn't required to be larger than #6 copper. Is this true for any size service or is there a limit to the size of service?

 

[Volta]

If the only electrodes that I am using for a service are two 5/8" x 8' ground rods then according to 250.66 (A) the grounding electrode conductor isn't required to be larger than #6 copper. Is this true for any size service or is there a limit to the size of service?

No limit, #6 to rods and plates is ok.

 

[arits74]

someone needs to tell our inspector that ,he makes us use 4 bare on 400 amp service,lol

 

[Dennis Alwon]

someone needs to tell our inspector that ,he makes us use 4 bare on 400 amp service,lol

Where does that come from. T. 250.66 would require #2 or possible #1/0 for a 400 amp service. But as noted #6 is all that is required.

Show the inspector art. 250.53(E)

250.53(E) Supplemental Electrode Bonding Connection Size. Where the supplemental electrode is a rod, pipe, or plate electrode, that portion of the bonding jumper that is the sole connection to the supplemental grounding electrode shall not be required to be larger than 6 AWG copper wire or 4 AWG aluminum wire.

 

[Volta]

...
Show the inspector art. 250.53(E)

But that is for supplemental.

The OP states that the two rods are the only electrodes present, so the first one is not supplemental. We should use 250.66(A).

If the only electrodes that I am using for a service are two 5/8" x 8' ground rods then according to 250.66 (A) the grounding electrode conductor isn't required to be larger than #6 copper. Is this true for any size service or is there a limit to the size of service?

 

[Dennis Alwon]

But that is for supplemental.

The OP states that the two rods are the only electrodes present, so the first one is not supplemental. We should use 250.66(A).

You are correct-- I didn't read close enough but either way a rod only needs #6