单项选择题
A.蓄电池开关 B.受电弓故障隔离开关 C.接地隔离开关 D.劈相机故障隔离开关
A.5匝 B.6匝 C.7匝 D.8匝
A.5~10mm B.6~12mm C.7~14mm D.8~16mm