Dual power automatic transfer switch automatically switches between normal power and reserve power. The switch prioritizes normal power. When normal power is available, the switch connects to normal power. If normal power fails and reserve power is available, it automatically transfers to reserve power. This device does not turn the generator on or off. Press the button to select Automatic mode for automatic switching between power sources. Press the button to select Manual mode for manual control of power source selection. This automatic transfer switch is a terminal-type device designed for use with 3-phase 4-wire or 1-phase 2-wire dual power supply systems, AC 50/60Hz, rated voltage 230V, and rated current up to 63A. It monitors Phase A voltage from both normal and reserve power sources, detecting loss of voltage or phase failure. Upon detection, it automatically transfers connected load circuits from the failed source to the active source to maintain power supply. Note: Power will be interrupted briefly during switching. Rated voltage: AC 230V 50/60Hz Maximum current: 63A Color: Grey + Black + Blue Material: PC plastic Package includes: 1 x Automatic Transfer Switch Other items not included. Note: Lighting and display differences may cause slight color variations between the product image and actual item. Measurement error allowed is +/- 1-3 cm.