Dịch vụ & Phân phốiCâu 57 / 521
Under the 10-ft feeder tap rule, the tap conductors must have an ampacity not less than what value relative to the load and the device they supply?
a.25% of the feeder OCPD
b.Equal to the feeder OCPD
c.50% of the feeder ampacity
d.The load served, and at least the rating of the device/overcurrent it supplies
Giải thích
Per 240.21(B)(1), 10-ft tap conductors must have an ampacity not less than the combined computed load and not less than the rating of the device or OCPD they terminate in. Fixed percentages of the feeder OCPD/ampacity are not the correct basis for the 10-ft rule.
Trích dẫn luật: 2023 NEC §240.21(B)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- Service-entrance conductors must have an ampacity not less than which of the following?
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