Equipment & SystemsQuestion 250 of 521
Which motor current rating is used to select the running overload (overcurrent) protection device?
a.The Table 430.250 full-load current
b.The motor nameplate full-load amperes
c.The locked-rotor current from Table 430.251
d.250% of the full-load current
Explanation
NEC 430.6(A)(2) and 430.32 base overload protection on the motor's nameplate full-load amperes, because overloads protect the actual motor. The table FLC is used for conductors and short-circuit protection, not overload sizing.
Law Reference: 2023 NEC §430.32Practice all 521 questions free — no signup required.
Related questions on this topic
- 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?
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- When sizing branch-circuit conductors and short-circuit/ground-fault protection for a standard motor, which current value does the NEC require you to use?
- 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)?
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