Calculations第 26 / 110 题
Six current-carrying THHN conductors share one raceway. If the 90 C ampacity of #6 Cu is 75 A, what is the adjusted ampacity after the fill adjustment factor for 4-6 conductors?
a.75 A
b.60 A
c.55 A
d.52.5 A
解析
For 4 to 6 current-carrying conductors, apply an 80% adjustment factor: 75 A x 0.80 = 60 A.
法律依据: 2023 NEC Table 310.15(C)(1)免费刷完整 110 道题库 — 无需注册。
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