Services & DistributionCâu 48 / 110
An emergency system must be capable of supplying power to its loads within what maximum time after normal supply is lost?
a.60 seconds
b.30 seconds
c.120 seconds
d.10 seconds
Giải thích
Emergency systems must restore power to life-safety loads within 10 seconds of loss of the normal source.
Trích dẫn luật: 2023 NEC 700.12Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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