National Electrical Installation Standards

Standards as High as Your Own

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Wednesday, July 8, 2020

Question:

Hello Code Friends,

What is the standard (or is there one) for selecting proper lug barrel size for a given AWG wire size?

Scott Alsop

A

Answer:

Hi Scott,

Thanks for the question. The NEC includes specific rules for terminations (including selection of proper lug size) in Section 110.14 of the NEC. Section 110.3(B) addresses the use and installation that requires installations to be in accordance to the manufacturer's installation instructions. The lug should be suitable for the size of the conductor and the conductor material. Termination tightness (torque requirements) are covered in both of these sections and are typically provided in markings on the equipment.

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