Wiring Methods & Materials第 62 / 120 题
When more than two conductors are installed in a raceway, what is the maximum permitted percentage of the raceway cross-sectional area they may occupy?
a.53 percent
b.31 percent
c.40 percent
d.60 percent
解析
Chapter 9, Table 1 allows 53 percent fill for one conductor, 31 percent for exactly two conductors and 40 percent for three or more. The 60 percent value applies only to a nipple not exceeding 24 inches in length between boxes or enclosures.
法律依据: 2023 NEC Chapter 9, Table 1免费刷完整 120 道题库 — 无需注册。
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