S? d?ng cho h? th?ng ?i?n h? th? khi ngu?n c?p ph? t?i b? gián ?o?n B? chuy?n m?ch t? ??ng, giám sát và chuy?n ??i gi?a hai ngu?n ?i?n Chuy?n m?ch 3 v? trí I - O - II- The ensured a gradual and steady breaking ability whatever the running voltage via an open up Procedure utilizing a individual breaking spring.- Each and every phase is molded a