A.電源空開(kāi)下口無(wú)接地或短路情況B.電源無(wú)混線現(xiàn)象C.電源正負(fù)極接線正確D.裝置失電應(yīng)可報(bào)警
A.接地B.絕緣C.隔離D.加壓
A.1B.2C.5D.10