找考题网-背景图
单项选择题

A.开关合上B.开关合上,相连刀闸断开C.开关断开,相连刀闸断开,相连接地刀闸断开D.开关合上,相连刀闸合上开……

开关“热备用”状态的定义是()

A.开关合上
B.开关合上,相连刀闸断开
C.开关断开,相连刀闸断开,相连接地刀闸断开
D.开关合上,相连刀闸合上