It offers superb insulation performance even in locations destroyed by salt or pollution with its anti-pollution style.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 three v? trí I - O - II– ?i?u ch?nh th?i gian chuy?n m?ch tr?c ti?p trên m?t