Off line UPS System
Again the two switches are used in this type of ups as online ups. The difference is that here the main static switch remains normally ON and UPS static switch remains normally OFF.
Here the load is directly connected to the main supply through main static switch. Under the condition of power failure, main static switch operates to disconnect the mains from the load and then ups static switch becomes ON to connect the load batter by bank through circuit. Battery bank suppliers the power to the load.