The ATS change-over switch is designed to sense when an electric utility outage occurs. If it happens, the ATS switch tells the backup generator to start. Once the ATS switch sees that the generator is ready to provide electric power, it breaks the home's connection to the electric utility and connects the generator to the home's main electrical panel. The generator supplies power to the home's electric load, but is not connected to the electric utility.
When utility power returns, the transfer switch will transfer back to utility power and command the generator to turn off.
This ATS switch can be also used in between 2 identical power supplies such as an inverter power-mains power or a solar power-generator power.
2 Pole Switch is used for 1 Phase Power supply. 4 Pole switch is used for 3 Phase and Neutral Power supply.