Limit switches are one of the most common presence sensing devices used in industrial controls. Activated when an object makes physical contact with the actuator, they provide an electric or pneumatic signal. Choose limit switch type based on environmental factors and available space, then choose actuator style based on the mechanical setup of the application.
A limit switch is an electromechanical device that consists of an actuator mechanically linked to a set of contacts. When an object comes into contact with the actuator, the device operates the contacts to make or break an electrical connection.