Motors & EquipmentPregunta 94 de 120
A continuous-duty motor over 1 horsepower has no marked service factor and no marked temperature rise. What is the maximum overload device rating as a percentage of nameplate full-load current?
a.140 percent
b.125 percent
c.115 percent
d.175 percent
Explicación
Motors that carry neither a service factor of 1.15 or greater nor a marked temperature rise of 40 degrees C or less are limited to 115 percent of nameplate current, because there is less thermal margin available. The 125 percent value applies to the better-rated motors, 140 percent is the permitted increase when the motor will not start, and 175 percent is a fuse sizing percentage.
Referencia Legal: 2023 NEC §430.32(A)(1)Practica las 120 preguntas gratis — sin registro.
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