1. Automatic transfer switch can switch to Normal power or reserve power automatically. Please the switch can' turn on or turn off the generator. This switch Normal power first. If normal power on, the switch will switch to Normal power. If normal power off, and reserve power on, the switch will switch to reserve power. 2.Wire Press the button to Automatic, the switch will switch to Normal power or reserve power automatically. Press the button to Manual, Then you have to switch the Direction manually. 3. The Automatic Transfer Switch is terminal type automatic transfer device. It's suitable for 3 phases 4 wires (or 1 phase 1 wire) grid with AC 50/60Hz, rated voltage 230V and rated current up to 63A. When one power goes wrong (only test normal Phase A voltage and reserve Phase A voltage, only test loss voltage or loss phase),it will automatic connect one or load circuits from one power to the other power automatically, to normal power supply of load circuits. Rated voltage: AC230V 50/60HZ : power will be interrupted when Switching. Max current: 63A. Color: Grey+Black+Blue Material: PC plastic Package Contents: 1 x Automatic Transfer Switch Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.