Services & DistributionQuestion 44 of 521
Service-entrance conductors must supply a computed load of 160 A continuous. What minimum conductor ampacity is required per 230.42?
a.160 A
b.128 A
c.175 A
d.200 A
Explanation
Per 230.42(A), service conductors must have an ampacity of at least 125% of continuous load: 160 A x 1.25 = 200 A. 160 A ignores the factor, 128 A reduces the load, and 175 A is insufficient.
Law Reference: 2023 NEC §230.42Practice all 521 questions free — no signup required.
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