Services, Grounding & BondingPregunta 42 de 120
Using the dwelling conductor table, what is the minimum copper conductor size for a 400-ampere single-phase dwelling service?
a.600 kcmil
b.500 kcmil
c.350 kcmil
d.400 kcmil
Explicación
The dwelling service and feeder table lists 400 kcmil copper for a 400-ampere single-phase dwelling service, reflecting the 83 percent allowance. Table 310.16 alone would push you toward 600 kcmil, and 350 kcmil is the table value for a 350-ampere service.
Referencia Legal: 2023 NEC §310.12Practica las 120 preguntas gratis — sin registro.
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