A.應(yīng)采用同步接通與斷開(kāi)的觸點(diǎn)
B.應(yīng)采用先斷開(kāi)，后接通的觸點(diǎn)
C.應(yīng)采用先接通、后斷開(kāi)的觸點(diǎn)
D.對(duì)觸點(diǎn)的斷開(kāi)順序不作要求

A.壓板下口對(duì)地為＋110V左右，上口對(duì)地為－110V左右
B.壓板下口對(duì)地為＋110V左右，上口對(duì)地為0V左右
C.壓板下口對(duì)地為0V，上口對(duì)地為－110V左右
D.壓板下口對(duì)地為＋220V左右，上口對(duì)地為0V