Dịch vụ & Phân phốiCâu 84 / 521
Overhead service conductors (service drop) over a residential driveway with no truck traffic must maintain a minimum vertical clearance above grade of:
a.10 ft
b.12 ft
c.15 ft
d.18 ft
Giải thích
Per 230.24(B), 12 ft (3.7 m) is required over residential property and driveways where the voltage does not exceed 300 V to ground. The 10 ft clearance applies only over limited areas like accessible-to-pedestrians-only locations, while 18 ft applies to public streets/truck traffic.
Trích dẫn luật: 2023 NEC §230.24Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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