Wiring Methods & Materials第 68 / 120 题
A GFCI-protected 120-volt, 20-ampere residential branch circuit is direct buried in a yard. What is the minimum cover?
a.18 inches
b.6 inches
c.12 inches
d.24 inches
解析
Residential branch circuits rated 120 volts or less and 20 amperes or less that have GFCI protection may be buried with only 12 inches of cover, because a ground fault from a dig-in will clear immediately. Without GFCI protection the general 24-inch requirement applies, and the 6- and 18-inch values belong to metal and nonmetallic raceways.
法律依据: 2023 NEC Table 300.5免费刷完整 120 道题库 — 无需注册。
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