A.6A B.2/3A C.0A D.2A
A.10/20/30 B.10/10/0 C.10/20/10 D.10/10/10
A.保證負載的相電壓相等 B.保證負載的線電壓相等 C.保證負載的相電流相等 D.保證負載的線電流相等