National Electrical Installation Standards

Standards as High as Your Own

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Friday, February 23, 2018

Question:

Article 501, 501.15 C 6 states that the conductor or optical fill, the cross section area of seal shall not exceed 25% of the cross section area of a ridged conduit of same trade size?? is this for pouring in chico into EYS, don't understand this, conduit fill vs. seal off fill when its the same conduit?????

Mike Garcia

A

Answer:

Hey Mike thanks for your question, that is a lot of question marks. Yes, the 25 % fill limit stated in 501.15(C)(6) is because of the preparation and sealing necessary for hazardous (classified) locations. If standard sealing fittings are used they are limited to 25% even though the same size conduit can usually be filled to 40%. Either special sealing fittings with a 40% fill limit or larger ones with reducing fittings must be used if you want the 40% fill.

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