Dịch vụ & Phân phốiCâu 73 / 521
The short-circuit current rating (SCCR) of equipment such as a panelboard means the equipment can:
a.Withstand the available fault current at its terminals without extensive damage until the overcurrent device clears
b.Carry continuous load indefinitely
c.Interrupt fault current by itself
d.Operate at 125% of its rating
Giải thích
Per 110.10, the SCCR ensures the assembly can safely withstand the let-through energy of the available fault current until the protective device opens, preventing extensive damage. It is not a measure of continuous carrying capacity, and the panelboard itself does not interrupt the fault.
Trích dẫn luật: 2023 NEC §110.10Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- A feeder is protected by a 100 A overcurrent device. Using Table 250.122, the minimum size copper equipment grounding conductor is:
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