A.5% B.10% C.15% D.1%
A.電動機停轉(zhuǎn) B.電動機溫度過高而冒煙 C.轉(zhuǎn)速變慢 D.電動機外殼帶電
A.電刷 B.轉(zhuǎn)子繞組 C.油環(huán) D.輔助設(shè)備