Branch Circuits & Feeders第 25 / 120 题
Using the dwelling service and feeder conductor table, what is the minimum copper conductor size for a 200-ampere single-phase dwelling service?
a.1/0 AWG
b.3/0 AWG
c.4/0 AWG
d.2/0 AWG
解析
For single-phase dwelling services and the main power feeder, conductors are permitted to be sized at 83 percent of the service rating, and the dwelling table lists 2/0 copper for a 200-ampere service. The 3/0 answer is what Table 310.16 alone would require without the dwelling allowance, and 1/0 is below what the dwelling table permits.
法律依据: 2023 NEC §310.12免费刷完整 120 道题库 — 无需注册。
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