Dịch vụ & Phân phốiCâu 18 / 521
A 4/0 AWG copper THHN conductor (90 C, base 260 A) is in an ambient of 45 C. Using the 0.87 correction factor, what is the corrected ampacity?
a.226 A
b.247 A
c.195 A
d.260 A
Giải thích
260 A x 0.87 = 226 A after applying the 41-45 C temperature-correction factor from Table 310.15(B) to the 90 C column. 260 A ignores correction, and the other values use wrong factors.
Trích dẫn luật: 2023 NEC §310.15(B)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- Using the 75 C column of Table 310.16, what is the allowable ampacity of a 3/0 AWG copper conductor?
- What is the 75 C ampacity of a 4/0 AWG copper conductor per Table 310.16?
- At the 75 C column of Table 310.16, what is the ampacity of a 1/0 AWG copper conductor?
- Six current-carrying conductors are installed in a single raceway. What adjustment factor applies to their ampacity?
- How many current-carrying conductors can be in a raceway before an adjustment (fill derating) factor must be applied?
- For equipment terminals on a circuit rated 100 A or less (not marked otherwise), which temperature column must be used to size conductors?
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