Motors & EquipmentPregunta 87 de 120
For the same 34-ampere motor, what is the maximum dual-element time-delay fuse permitted at the standard percentage?
a.60 amperes
b.70 amperes
c.50 amperes
d.90 amperes
Explicación
Dual-element time-delay fuses are permitted at 175 percent of full-load current: 34 x 1.75 = 59.5 A, and because that is not a standard rating the next standard size of 60 amperes is used. The 90-ampere answer belongs to the inverse-time breaker at 250 percent, and 50 amperes falls below the calculated value.
Referencia Legal: 2023 NEC Table 430.52(C)(1)Practica las 120 preguntas gratis — sin registro.
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