Equipment & SystemsQuestion 267 of 521
A 30 HP, 460 V, three-phase motor has an FLC of 40 A. What is the minimum ampere rating of the motor disconnecting means (115% of FLC)?
a.40 A
b.44 A
c.46 A
d.50 A
Explanation
NEC 430.110(A) requires the disconnect to be at least 115% of FLC: 40 x 1.15 = 46 A. 40 A ignores the factor, 44 A is 110%, and 50 A is 125% (used for conductors, not the minimum disconnect).
Law Reference: 2023 NEC §430.110Practice all 521 questions free — no signup required.
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