A.220V B.250V C.311V D.380V
A.相線之間 B.零線對(duì)地間 C.相線對(duì)零線間 D.相線對(duì)地間
A.相電流超前線電流30° B.線電流超前相電流30° C.相電流與線電流同相 D.相電流超前線電流60°