National Electrical Installation Standards

Standards as High as Your Own

Friday, November 30, 2018


Re: CQD answer published Friday, November 16, 2018 -Cables in Raceways

Is response to the question published November 16, 2018. You should also point out the correct conduit fill requirements when dealing with elliptical cables. This is found in note 9 to Table 1 from Chapter 9. This requires that a multiconductor cable, optical fiber cable or flexible cord of two or more conductors be treated as a single conductor. Elliptical cable must use the large diameter of the cable as a circle diameter. This can lead to conduits much larger than what the cable will actually fit in being necessary.

Regards, Jeff Bower



Hey Jeff thanks for your comment - great point. As you mentioned elliptical cables installed in raceways must use an area determined by using the major diameter of the ellipse as a circle diameter as stated in Note 9 to Table 1 in Chapter 9.

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