Equipment & SystemsQuestion 251 of 521
A motor nameplate reads 28 A full-load, service factor 1.0, temperature rise not marked. What is the maximum overload rating under NEC 430.32(A)(1)?
a.28 A
b.35 A
c.32.2 A
d.30.8 A
Explanation
Motors without a 1.15+ service factor or a 40C-or-less marked temperature rise are limited to 115% of nameplate FLA: 28 x 1.15 = 32.2 A. 125% (35 A) applies only to SF >=1.15 or <=40C-rise motors, and 30.8 A is 110%.
Law Reference: 2023 NEC §430.32Practice all 521 questions free — no signup required.
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