Branch Circuits & WiringQuestion 192 of 521
Per Chapter 9, Table 1, what is the maximum permitted fill percentage when only one conductor is installed in a conduit?
a.31%
b.40%
c.60%
d.53%
Explanation
A single conductor may fill up to 53% of the conduit's internal area per Table 1. 31% is for two conductors, 40% for three or more, and 60% is not a code value.
Law Reference: 2023 NEC Chapter 9, Table 1Practice all 521 questions free — no signup required.
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