Motors & EquipmentQuestion 85 of 120
That same motor has a nameplate full-load current of 32 amperes and a marked service factor of 1.15. What is the maximum separate overload device rating?
a.36.8 amperes
b.40 amperes
c.42.5 amperes
d.32 amperes
Explanation
Overload protection is based on the nameplate current, not the table value, and a service factor of 1.15 or greater permits 125 percent: 32 x 1.25 = 40 A. The 36.8-ampere answer applies the 115 percent factor used for motors with no marked service factor or temperature rise, and 42.5 amperes wrongly applies 125 percent to the table value of 34 A.
Law Reference: 2023 NEC §430.32(A)(1)Practice all 120 questions free — no signup required.
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