Equipment & SystemsQuestion 280 of 521
For the 100 HP, 460 V motor (FLC 124 A), what is the maximum dual-element (time-delay) fuse per Table 430.52 (175%)?
a.310 A
b.372 A
c.155 A
d.217 A
Explanation
Dual-element time-delay fuse: 175% of FLC = 124 x 1.75 = 217 A. 310 A is 250% (inverse-time breaker), 372 A is 300% (nontime-delay fuse), and 155 A is 125% (conductor factor).
Law Reference: 2023 NEC §430.52Practice all 521 questions free — no signup required.
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