Per 320.40, what must be installed at each termination of Type AC (armored) cable to protect the conductors from the cut edge of the metal armor?

Giải thích

Section 320.40 requires an insulating anti-short bushing, commonly called a red head, at each armored-cable termination to protect the conductor insulation from the sharp armor. A locknut or connector alone does not protect against the cut armor edge, and a grounding bushing serves a different purpose.