National Electrical Installation Standards

Standards as High as Your Own

Tuesday, February 12, 2019


Greetings to you folks at CQD, while looking up some information regarding the definition of "coated" and "uncoated" wire, I ran across a CQD at the following link:

In the answer part of that CQD is found this language: "The overall CSA of both bare copper and tinned copper for a given size was the same, therefore, you will find that the resistance values for tinned copper conductors is slightly more than that of bare copper."

My question is this: What is meant by "CSA" in this answer?  The word "diameter" would seem to make sense in place of "CSA," but I hate to assume…

Thanks in advance for your help!

Johnie Spruiell



Hey Johnie thanks for your question. Table 1 in Chapter 9 of the NEC has a heading titled "Cross-Sectional Area(%). The area can be determined from the diameter but it is often the area that is used in the NEC. Later tables, including Table 8 which includes coated and uncoated conductors, use only the term "area" so possibly there is an opportunity for making changes to be consistent.

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