National Electrical Installation Standards

Standards as High as Your Own

Tuesday, June 9, 2020


Comments to CQD 06/03/2020:

Regarding the June 2nd answer, you are correct on the 6" of free conductor but it is measured from where it emerges from its raceway, the wire must be long enough to extend 3 inches outside the opening of the box or the last extension. Thanks for continuing code question of the day I definitely enjoy it. Al Maline


Your answer indicated “There are also other NEC requirements for length of free conductor that must be provided, such as in Section 300.14, which is generally 6 inches of free conductor beyond the edge of the box opening.”


Comment: Section 300.14 does not require 6 inches beyond the edge of the box opening – that distance is taken from the entry point of the raceway. The required length beyond the edge of the box opening is 3 inches, not 6 inches. Scott Kauzlaric


Comment on Answer to CQD 06-03-2020: Not to be picky, just accurate, for your 06/02/20 answer regarding a 4" or 4-11/16" box or extension ring, the 6" of wire past the box opening is incorrect. The 6" measurement starts at the conduit our cable sheath and the minimum at the opening is 3". 300.14 Length of Free Conductors at Outlets, Junctions, and Switch Points. At least 150 mm (6 in.) of free conductor, measured from the point in the box where it emerges from its raceway or cable sheath, shall be left at each outlet, junction, and switch point for splices or the connection of luminaires or devices. Where the opening to an outlet, junction, or switch point is less than 200 mm (8 in.) in any dimension, each conductor shall be long enough to extend at least 75 mm (3 in.) outside the opening. Exception: Conductors that are not spliced or terminated at the outlet, junction, or switch point shall not be required to comply with 300.14. Richard Cressotti



These comments are all excellent observations and for contributing. Thanks for the correction on where the measurement is taken from for the 6 inches of free conductor. We appreciate the participation.

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