Branch Circuits & FeedersPregunta 28 de 120
A 5,000-watt, 240-volt single-phase electric heater operates continuously. What is the minimum standard branch-circuit overcurrent device rating?
a.30 amperes
b.20 amperes
c.25 amperes
d.35 amperes
Explicación
The load current is 5,000 / 240 = 20.8 A, and because the load is continuous the device must be rated at least 20.8 x 1.25 = 26 A, so the next standard rating is 30 A. The 20 A and 25 A answers either ignore the continuous factor or land below the calculated minimum, and 35 A is not the next standard size above 26 A.
Referencia Legal: 2023 NEC §210.20(A)Practica las 120 preguntas gratis — sin registro.
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