An toànCâu 435 / 521
A 480V panel is installed so the worker stands between two energized sections with exposed live parts on both sides of the working space (Condition 3). What minimum working-space depth is required?
a.4 feet
b.3 feet
c.3½ feet
d.6 feet
Giải thích
For 151-600V equipment, Condition 3 (exposed live parts on both sides of the worker) requires a minimum 4-foot clear depth. 3 feet is Condition 1 and 3½ feet is Condition 2 at this voltage; 6 feet is not required for 480V.
Trích dẫn luật: 2023 NEC §110.26Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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