Code Quiz: Mounting a Box with Screws

Aug. 17, 2017
NEC Rules on Mounting a Box with Screws

Fill in the blank. When securing a box, screws shall not be permitted to pass through the box unless exposed threads in the box are ______ using approved means to avoid abrasion of the conductor insulation. Mounting holes made in the field shall be _______.

A) coated / threaded
B) painted / tapered
C) protected / approved
D) covered / identified

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Answer: C

As outlined in a portion of Sec. 314.23(B)(1), “Screws shall not be permitted to pass through the box unless exposed threads in the box are protected using approved means to avoid abrasion of conductor insulation. Mounting holes made in the field shall be approved.”

Owen is the owner and president of National Code Seminars and the holder of master electrician certifications in 46 states. He can be reached at [email protected].

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Steven Owen

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