Wiring Methods & Materials第 82 / 120 题
What is the minimum trade size of EMT required for twenty-four 12 AWG THHN conductors?
a.One inch
b.Three-quarter inch
c.One and one-quarter inch
d.One and one-half inch
解析
Annex C, Table C1 shows one inch EMT accepts twenty-six 12 AWG THHN conductors, so twenty-four fit. Three-quarter inch holds only sixteen and is too small, while one and one-quarter inch holds far more than needed. Remember that twenty-four current-carrying conductors would also trigger a 45 percent ampacity adjustment.
法律依据: 2023 NEC Annex C, Table C1免费刷完整 120 道题库 — 无需注册。
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