A proximity switch is a position switch that can be operated without direct mechanical contact with moving parts. When the object is approaching and the sensing surface of the switch is at the action distance, the switch can be actuated without mechanical contact and any pressure to drive the DC electrical appliance or provide control instructions to the computer (plc) device. ATO proximity switch is a non-contact switch. It not only has the characteristics of a limit switch and microswitch but also has sensing performance.