Dịch vụ & Phân phốiCâu 51 / 521
For a single service, what is the maximum number of service disconnecting means permitted (for one set of service-entrance conductors)?
a.6
b.8
c.4
d.10
Giải thích
Per 230.71, the service disconnecting means for each service is limited to a maximum of 6, each in a separate enclosure or in listed switchgear/switchboard. 4 is more restrictive than required, and 8 or 10 exceed the code maximum.
Trích dẫn luật: 2023 NEC §230.71Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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