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Wednesday, July 6, 2022

Question:

Hello,

I enjoy the CQD each morning. There is a debate in our office about the maximum size grounding electrode conductor required for connecting to a single ground rod electrode. Some say 6AWG copper, others say Table 250.66 is the general rule and it depends on the size of the largest ungrounded service entrance conductor. Which is correct?

Thanks for the opinion.

Andy Sauer

A

Answer:

Hello Andy,

Thanks for the commments and the question. Section 250.66 and Table 250.66 are the general rules for sizing grounding electrode conductors (GECs). However, Section 250.66(A) provides relief from sizing using the Table values but only when the GEC is connected to a single ground rod electrode. 

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