A.4B.3C.2D.1
A.BT供電B.AT供電C.直接供電D.單邊供電
A.合斷路器輔助常閉接點(diǎn)B.斷路器輔助常開(kāi)接點(diǎn)C.常開(kāi)接點(diǎn)D.常閉接點(diǎn)