Wiring Methods & Materials第 65 / 120 题
What is the minimum cover for a direct-buried UF cable installed in a residential yard on a 120-volt, 20-ampere circuit that is NOT GFCI protected?
a.18 inches
b.24 inches
c.12 inches
d.6 inches
解析
Direct-buried cables and conductors under all locations not otherwise covered require 24 inches of cover. The 12-inch reduction applies only to residential branch circuits rated 120 volts or less, 20 amperes or less, and provided with GFCI protection, so removing the GFCI removes the reduction. The 6-inch and 18-inch values belong to metal and nonmetallic raceways respectively.
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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