Services & Distribution第 55 / 110 题
A concrete-encased electrode (Ufer) must consist of at least how many feet of #4 or larger rebar or bare #4 Cu conductor?
a.10 ft
b.15 ft
c.20 ft
d.25 ft
解析
A concrete-encased electrode requires at least 20 ft of 1/2-in (or larger) rebar or 20 ft of bare #4 Cu encased in the concrete footing/foundation.
法律依据: 2023 NEC 250.52(A)(3)免费刷完整 110 道题库 — 无需注册。
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