Equipment & SystemsQuestion 248 of 521
For the same 5 HP, 230 V motor (FLC 15.2 A), what is the maximum instantaneous-trip circuit breaker setting permitted by Table 430.52?
a.45.6 A
b.38 A
c.76 A
d.121.6 A
Explanation
Table 430.52 permits an instantaneous-trip breaker up to 800% of FLC for most motors: 15.2 x 8 = 121.6 A. 45.6 A is 300%, 38 A is 250%, and 76 A is 500%.
Law Reference: 2023 NEC §430.52Practice all 521 questions free — no signup required.
Related questions on this topic
- For a 20 HP, 460 V, three-phase motor (FLC 27 A), what is the maximum inverse-time circuit breaker rating for branch-circuit short-circuit and ground-fault protection, using the 250% value of Table 430.52?
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