Motors & EquipmentCâu 95 / 120
Where must a motor disconnecting means be located relative to the motor?
a.Within 25 feet of the motor in all cases
b.In sight from the motor location and the driven machinery, unless it is capable of being locked in the open position
c.Anywhere on the same floor level as the motor
d.In sight from the controller only, with no rule about the motor
Giải thích
A disconnect must be in sight from the motor and driven machinery so a technician working on the equipment can see that it is open; the alternative is a disconnect elsewhere that is capable of being individually locked in the open position with the locking means remaining in place. In sight means visible and not more than 50 feet away, and a separate rule requires a disconnect in sight from the controller.
Trích dẫn luật: 2023 NEC §430.102(B)Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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