Wiring Methods & Materials第 69 / 120 题
How must electrical metallic tubing be secured and supported on a normal horizontal run?
a.Secured within 3 feet of each box and supported at least every 10 feet
b.Secured within 12 inches of each box and supported every 4 and 1/2 feet
c.Secured within 3 feet of each box and supported every 6 feet
d.Support is required only every 10 feet with no requirement near boxes
解析
EMT must be securely fastened within 3 feet of every box, cabinet or termination and supported at intervals not exceeding 10 feet. The 12-inch and 4 and 1/2-foot figures belong to Type NM and Type AC cable, and the 6-foot interval is the MC cable support spacing.
法律依据: 2023 NEC §358.30(A)免费刷完整 120 道题库 — 无需注册。
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