Equipment & SystemsQuestion 243 of 521
A single continuous-duty 25 HP, 460 V, three-phase motor has an FLC of 34 A (Table 430.250). What minimum conductor ampacity is required for its branch circuit?
a.34 A
b.38.25 A
c.42.5 A
d.46.75 A
Explanation
NEC 430.22 requires branch-circuit conductors for a single continuous-duty motor to be sized at 125% of FLC: 34 A x 1.25 = 42.5 A. 34 A ignores the 125% factor, 38.25 A uses 112.5%, and 46.75 A uses 137.5%.
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