Wiring Methods & Materials第 81 / 120 题
What is the maximum fill percentage when exactly two conductors are installed in a raceway?
a.40 percent
b.31 percent
c.53 percent
d.60 percent
解析
Two conductors are limited to 31 percent fill, a lower figure than the 40 percent allowed for three or more, because two round conductors of similar size can jam in a bend and damage insulation during the pull. One conductor may fill 53 percent, and 60 percent applies only to a nipple 24 inches or shorter.
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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