Article 320

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Armored Cable: Type AC 320.30 Secured and Supported Part II. Installation This section was reorganized with editorial changes to add clarity and uniform interpretation. New subsection (A) General, gives a title to the opening paragraph and includes requirements that apply generally. The requirements for securing and supporting have been separated into (B) and (C), as they are two different issues. (A) General. Type AC cable must be supported and secured by staples, cable ties, straps, hangers, or similar fittings, designed and installed not to damage the cable. (B) Securing. Type AC cable must be secured within 12 in. of every outlet box, junction box, cabinet, or fitting and at intervals not exceeding 4 1/2 ft where installed on or across framing members. Figure 320-1 Author’s Comment: Type AC cable is considered secured when installed horizontally through wooden or metal framing members [320.30(C)]. (C) Supporting. Type AC cable must be supported at intervals not exceeding 4 1/2 ft. Cables installed horizontally through wooden or metal framing members are considered secured and supported where such support doesn’t exceed 41/2 ft intervals. Figure 320-2 (D) Unsupported Cables. Type AC cable can be unsupported where the cable is: (1) Fished through concealed spaces in finished buildings or structures, where support is impracticable; or (2) Not more than 2 ft long at terminals where flexibility is necessary; or (3) Not more than 6 ft long from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment within an accessible ceiling. For the purposes of this section, Type AC cable fittings are permitted as a means of cable support. Figure 320-3

Figure 320-1 (Click on image to enlarge) Figure 320-2 (Click on image to enlarge) Figure 320-3 (Click on image to enlarge)