Thiết bị & Hệ thốngCâu 307 / 521
Rapid shutdown requires that controlled conductors more than 1 foot outside the array boundary be limited to what within 30 seconds?
a.80 volts within 10 seconds
b.30 volts within 30 seconds
c.50 volts within 1 minute
d.0 volts instantly
Giải thích
Section 690.12 requires that conductors leaving the array boundary be reduced to no more than 30 volts within 30 seconds of rapid-shutdown initiation. This protects firefighters and responders; the 80-volt limit applies only inside the array boundary, not to the outside conductors.
Trích dẫn luật: 2023 NEC §690.12Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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