A.<50mAB.<30mAC.<100mAD.<300mA
A.轉(zhuǎn)子的軸B.定子空心圓環(huán)C.動觸點D.靜觸點
A.0.4s~十幾秒B.0.4~180sC.0.4s~1hD.0.6s~3h