Advanced WiringCâu 74 / 110
Low-voltage lighting systems covered by Article 411 are limited to a maximum circuit voltage of:
a.24 V
b.30 V
c.15 V
d.12 V
Giải thích
Article 411 low-voltage lighting systems operate at not more than 30 V (or 60 V DC for wet contact limits), commonly through a listed power supply.
Trích dẫn luật: 2023 NEC 411.5Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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