National Electrical Installation Standards

Standards as High as Your Own

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Thursday, September 21, 2017

Question:

Extending an existing circuit with reduced equipment ground

Hello Charlie, (and now your crew)

Thank you for what you do! I am older than dirt and grew up (sort of) on a farm without the benefit of electricity. Makes you wonder how I became an electrical inspector – right?

Question that I have not been asked before:  Can a 12/2G (with a 14 AWG equipment ground) be extended on a 20 amp circuit?

Thank you, Ray Paulson

A

Answer:

Hey Ray thanks for your question and the kind words. Many of us can probably be considered old but dirt has been around much longer. Several methods of providing equipment grounding connections are described in 250.130(C) as you know. No mention is made of requiring the existing portion of a circuit to be changed to meet the rules in 250.122 so it seems this is a judgment decision to be made by the AHJ. Depending on the specific installation 250.4(A)(5) could also be a consideration.

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