Services & DistributionCâu 49 / 110
A legally required standby system must supply its loads within what maximum time after loss of normal power?
a.60 seconds
b.10 seconds
c.30 seconds
d.120 seconds
Giải thích
Legally required standby systems must be able to supply their loads within 60 seconds of a normal-source failure.
Trích dẫn luật: 2023 NEC 701.12Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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