Wiring Methods & MaterialsPregunta 83 de 120
Conductors installed in an underground raceway in a wet location must have which characteristic?
a.A nylon jacket, which by itself qualifies the conductor for wet locations
b.Any thermoplastic insulation, since the raceway keeps water out
c.Insulation rated 90 degrees C, regardless of wet-location listing
d.Insulation listed for use in wet locations, such as THWN or THWN-2
Explicación
Raceways in underground and other wet locations are considered wet inside, so the conductors must carry a wet-location listing such as THWN, THWN-2 or XHHW. The W in the type designation is what matters; plain THHN without the dual THWN-2 marking is a dry- and damp-location conductor, and a temperature rating or nylon jacket alone does not confer a wet-location listing.
Referencia Legal: 2023 NEC §310.10(C)Practica las 120 preguntas gratis — sin registro.
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