Motors & EquipmentPregunta 88 de 120
A 5-horsepower, 230-volt single-phase motor has a table full-load current of 28 amperes. What is the minimum copper branch-circuit conductor at 75 degrees C terminations?
a.10 AWG
b.12 AWG
c.8 AWG
d.6 AWG
Explicación
The conductor must carry 28 x 1.25 = 35 A. In the 75 degrees C column, 10 AWG copper is exactly 35 A and qualifies, while 12 AWG at 25 A does not. Note that 240.4(D) limits ordinary 10 AWG circuits to a 30-ampere device, but motor branch-circuit protection is sized under Article 430 instead.
Referencia Legal: 2023 NEC §430.22Practica las 120 preguntas gratis — sin registro.
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