Wiring Methods & Materials第 61 / 120 题
What is the minimum trade size of EMT required for nine 12 AWG THHN conductors?
a.One-half inch
b.Three-quarter inch
c.One inch
d.One and one-quarter inch
解析
Annex C, Table C1 shows that one-half inch EMT accepts nine 12 AWG THHN conductors, exactly meeting the requirement. Three-quarter inch EMT holds sixteen and one inch holds twenty-six, so both are larger than the minimum. Annex C may be used directly whenever all conductors are the same size and insulation type.
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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