Dịch vụ & Phân phốiCâu 103 / 521
When circuit conductors are run in parallel in multiple raceways, the equipment grounding conductor in each raceway must be:
a.Divided proportionally between raceways
b.Omitted in all but one raceway
c.One size smaller in each raceway
d.Sized in full, based on the circuit overcurrent device, in each raceway
Giải thích
Per 250.122(F), where conductors are run in parallel in separate raceways or cables, a full-size equipment grounding conductor sized per Table 250.122 (based on the circuit OCPD) must be installed in each raceway. It cannot be divided, reduced, or omitted, because each raceway must carry a complete fault path.
Trích dẫn luật: 2023 NEC §250.122Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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