Wiring Methods & Materials第 73 / 120 题
What is the maximum support spacing for a 1-inch trade size rigid PVC conduit?
a.6 feet
b.5 feet
c.3 feet
d.10 feet
解析
PVC expands and sags with temperature, so support spacing depends on trade size: one-half through 1 inch is supported every 3 feet, 1 and 1/4 through 2 inch every 5 feet, and larger sizes at progressively longer intervals. The 10-foot spacing belongs to EMT and rigid metal conduit, which are far stiffer.
法律依据: 2023 NEC §352.30(B)免费刷完整 120 道题库 — 无需注册。
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