4P Mini Dual Power Automatic Transfer Switch ATS CB Grade Small Generator Changeover Switch 50Hz 60Hz 400V Item Type: Double Power Automatic Transfer Switch Material: PC Rated Voltage: 400V Frequency: 50 or 60Hz Number of Poles: 4 Segmentation Capacity: 35KA ATSE: CB grade Rated Current: 63A Working Principle:  This series of dual power supply controller and drive mechanism power supply signal depends on the A phase and N line of the common switch or standby switch inlet port. Dual power supply in automatic state, when the incoming phase A and N common switch voltage is normal (AC190 to 240v), the common switch will be closed in priority regardless of whether the common power B.C and standby switch a.b.c, N voltage is normal. At the same time, the power supply indicator and the common off indicator light up. When the incoming public switch A phase and line N have no voltage, and the incoming standby switch A phase and line N have normal voltage, the dual power supply turns to standby closure regardless of whether the normal switch B and standby switch C have normal voltage. The power indicator and standby closure indicator are on. Manual function, regardless of whether the voltage of normal power supply and standby power supply is available or not, manual operation mode can be used. For manual operation, the manual automatic button should be placed in the manual operation position. Push the handle to rotate clockwise to the terminal, the standby power vac open R open, the common power vac open N close. When pushing the handle to rotate counterclockwise to the terminal, the standby power switch R closes and the public power switch N opens.