Wiring Methods & MaterialsPregunta 79 de 120
How many 12 AWG conductors may be installed in a 4-11/16 inch by 2-1/8 inch square box with a volume of 42.0 cubic inches, assuming no clamps, devices or fittings?
a.21
b.20
c.16
d.18
Explicación
Each 12 AWG conductor requires 2.25 cubic inches, so 42.0 / 2.25 = 18.67, and the count must be rounded down to 18 whole conductors. The 21-conductor answer uses the 14 AWG allowance of 2.00 cubic inches, and 20 comes from rounding up rather than down.
Referencia Legal: 2023 NEC §314.16(A)Practica las 120 preguntas gratis — sin registro.
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