A.分配电箱→开关箱→总配电箱 B.总配电箱→开关箱→分配电箱 C.总配电箱→分配电箱→开关箱 D.开关箱→分配电箱→总配电箱
A.30mV,0.1S B.60mV,0.1S C.30mV,1S D.100mV,0.1S