Motors & EquipmentCâu 96 / 120
An air conditioning condensing unit nameplate reads minimum circuit ampacity 24.6 and maximum overcurrent protective device 40. What overcurrent device must be installed?
a.A 30-ampere device, the next standard size above the minimum circuit ampacity
b.A 25-ampere device to match the minimum circuit ampacity
c.A 50-ampere device sized at 125 percent of the marked maximum
d.A device not exceeding 40 amperes
Giải thích
The marked maximum overcurrent protective device value is a ceiling set by the equipment manufacturer and tested with the unit, so the installed device must not exceed 40 amperes; a smaller device is acceptable only if it will carry the starting current. The minimum circuit ampacity of 24.6 sizes the conductors, not the protective device, and nothing permits multiplying the marked maximum by another factor.
Trích dẫn luật: 2023 NEC §440.4(B)Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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