Thiết bị & Hệ thốngCâu 342 / 521
Low-voltage lighting systems covered by Article 411 are generally limited to what maximum voltage?
a.120 volts
b.60 volts
c.12 volts only
d.30 volts (or 15 volts where in direct contact with water)
Giải thích
Section 411.7 limits low-voltage lighting systems to a maximum of 30 volts (42.4 volts peak), reduced to 15 volts (21.2 volts peak) where the luminaires are installed in wet contact such as in a fountain. The 12-volt figure is a common operating voltage but is not the code maximum.
Trích dẫn luật: 2023 NEC §411.3Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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