Wiring Methods & Materials第 80 / 120 题
Direct-buried conductors emerging from grade must be protected by an approved enclosure or raceway from below grade to what height?
a.8 feet above finished grade
b.6 feet above finished grade
c.10 feet above finished grade
d.4 feet above finished grade
解析
Protection must extend from below grade to at least 8 feet above finished grade, and the underground portion must reach at least 18 inches below grade. Six feet leaves the conductors within easy reach of damage, and neither 4 nor 10 feet is the code value.
法律依据: 2023 NEC §300.5(D)(1)免费刷完整 120 道题库 — 无需注册。
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