Equipment & SystemsQuestion 247 of 521
A 5 HP, 230 V, three-phase motor has an FLC of 15.2 A. What is the maximum nontime-delay fuse permitted by Table 430.52 for branch-circuit protection?
a.26.6 A
b.38 A
c.45.6 A
d.121.6 A
Explanation
A nontime-delay fuse may be sized up to 300% of FLC: 15.2 x 3.00 = 45.6 A. 26.6 A is 175% (dual-element fuse), 38 A is 250% (inverse-time breaker), and 121.6 A is 800% (instantaneous-trip breaker).
Law Reference: 2023 NEC §430.52Practice all 521 questions free — no signup required.
Related questions on this topic
- A motor's nameplate shows a full-load current of 40 A and a service factor of 1.15. Under NEC 430.32(A)(1), what is the maximum overload device rating at 125% of nameplate FLA?
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