Quick Hits

EPISODE 4 — Securing and Supporting Type AC Cable (320.30)

Slide 1 — Hook "Today: the spacing rules for securing and supporting Type AC cable — plus when you're actually allowed to skip support altogether."

Slide 2 — 320.30(A)–(C) The standard rules

• (A) General: supported/secured with listed cable ties identified for that purpose, listed staples/straps/hangers/similar fittings, or other approved means that won't damage the cable. Type AC fittings/connectors themselves CAN serve as the support means.

• (B) Securing: within 12" of every outlet box/junction box/cabinet/fitting, and at intervals not exceeding 4½ ft, unless otherwise permitted.

• (C) Supporting: same 4½ ft interval rule. Horizontal runs installed through wooden/metal framing members (or similar supporting means) count as ALREADY supported/secured as long as those support points don't exceed 4½ ft apart — no extra clamps needed on top of that.

Slide 3 — 320.30(D) When support can be skipped entirely Type AC can be UNSUPPORTED and UNSECURED where:

1. Fished between access points through concealed spaces in a finished building, where supporting is impracticable.

2. No more than 2 ft long at terminals where flexibility is genuinely needed.

3. No more than 6 ft long from the last support point to the connection point at a luminaire/other equipment, IF that cable and connection point sit within an accessible ceiling.

Slide 4 — Quiz + CTA Q: "Type AC cable must generally be secured within what distance of an outlet box, junction box, cabinet, or fitting?" A) 6 in. B) 12 in. C) 18 in. D) 24 in.

✅ Answer: B — 320.30(B): within 12" (300 mm).

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