Services, Grounding & Bonding第 41 / 120 题
Service-entrance conductors supply 68 amperes of continuous load plus 120 amperes of noncontinuous load. What minimum ampacity must the conductors have?
a.205 amperes
b.188 amperes
c.235 amperes
d.225 amperes
解析
Service-entrance conductors follow the same rule as feeders: noncontinuous load plus 125 percent of continuous load, or 120 + (68 x 1.25) = 120 + 85 = 205 A. The 188-ampere answer simply adds the loads, while 225 and 235 amperes apply the 125 percent factor to the entire load instead of only the continuous portion.
法律依据: 2023 NEC §230.42(A)(1)免费刷完整 120 道题库 — 无需注册。
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