Wiring Methods & Materials第 70 / 120 题
How must Type NM cable be supported where it enters a box equipped with cable clamps?
a.Secured within 8 inches of the box and supported every 6 feet
b.Secured within 12 inches of the box and supported at least every 4 and 1/2 feet
c.Secured within 3 feet of the box and supported every 10 feet
d.Secured within 12 inches of the box and supported every 6 feet
解析
Type NM cable is secured within 12 inches of each box, cabinet or fitting and supported at intervals not exceeding 4 and 1/2 feet. The 8-inch figure applies to a single-gang nonmetallic box without clamps, the 3-foot and 10-foot values are EMT, and the 6-foot interval belongs to MC cable.
法律依据: 2023 NEC §334.30免费刷完整 120 道题库 — 无需注册。
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