Dịch vụ & Phân phốiCâu 105 / 521
For a 200 A service where the equipment and conductors are all rated for it, the conductor ampacity used for termination sizing is normally based on which temperature column?
a.90 degrees C
b.60 degrees C
c.75 degrees C
d.105 degrees C
Giải thích
Per 110.14(C), for circuits over 100 A (or conductors larger than 1 AWG), terminations are generally rated 75 degrees C, so the 75 degrees C column of Table 310.16 is used unless equipment is listed otherwise. The 90 degrees C column is only for derating starting points, and 60 degrees C applies to smaller circuits.
Trích dẫn luật: 2023 NEC §110.14Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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