Section § 393.28: Wiring systems.

Guidance Q&A

Question 1: Does a frame channel of a CMV constitute a protective ‘‘sheath or tube’’ as specified in §393.28?

Guidance: No. To be acceptable, a sheath or tube must enclose the wires throughout their circumference. In the absence of a sheath or tube, the group of wires must be protected by nonconductive tape, braid, or other covering capable of withstanding severe abrasion.