Branch Circuits & Feeders第 2 / 120 题
For that same 24-ampere continuous load, what is the minimum size copper branch-circuit conductor, assuming 75 degrees C terminations and THWN insulation?
a.12 AWG
b.10 AWG
c.8 AWG
d.14 AWG
解析
The conductor must carry at least 125 percent of the continuous load, or 30 A. In the 75 degrees C column of Table 310.16, 12 AWG copper is only 25 A, so it fails; 10 AWG copper is 35 A and is adequate, and 240.4(D) still allows a 30 A device on 10 AWG. Choosing 8 AWG is oversized for the minimum asked, and 14 AWG is limited to 15 A.
法律依据: 2023 NEC §210.19(A)免费刷完整 120 道题库 — 无需注册。
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