Thiết bị & Hệ thốngCâu 315 / 521
What is the maximum voltage permitted for a wet-niche underwater pool luminaire?
a.120 volts
b.150 volts
c.250 volts
d.60 volts
Giải thích
Section 680.23(A)(4) limits underwater luminaires to a maximum of 150 volts between conductors. Higher voltages such as 250 volts are not permitted for underwater pool lighting because of the shock hazard in and around water.
Trích dẫn luật: 2023 NEC §680.23Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- A luminaire installed in a wet location must be marked with what designation?
- Cord-connected luminaires, hanging luminaires, and similar equipment shall not have parts located within what zone measured from the bathtub rim or shower threshold, unless marked for damp or wet locations?
- The top of a wet-niche underwater pool luminaire lens (other than a listed low-voltage unit) must be installed at least how far below the normal water level?
- How must the wiring of an emergency system generally be arranged relative to all other wiring?
- Transfer equipment used for an emergency system must be what?
- For an optional standby system, what signage does the NEC require?
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