先闭后断换向开关接点的英文

make-before-break changeover switch contact

• 先:    earlier; before; f ...
• 闭:    close; shut
• 后:    behind; back; rear
• 断:    break; snap
• 换向:    changing-over; cha ...
• 开关:    Q-switching
• 接点:    contact; closing; ...