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Friday, October 22, 2021

Question:

Good Day,

I read the Code Question of the Day each afternoon. Always learning something about the Code. Are sheet metal screws, like the typical construction tek screws, suitable for connecting solid equipment grounding conductors to metal enclosures? Do I need to install a separate terminal lug?

Appreciate your input on this.

Adam Gray

A

Answer:

Hi Adam,

Based on the information provided in the question, the answer is no. Section 250.8(A) provides eight list items that are suitable for use in connecting solid equipment grounding conductors to equipment. Item (6) in this list indicates that thread-forming machine screws that engage not less than two threads in the enclosure would be suitable. Typical sheet metal screws (tek screws) usually have threads that are too coarse and would not meet this requirement.

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