Limit switches are electromechanical or solid state devices that require the physical contact of an object with the switch’s actuator to make the contacts change state.

Linear limit switches are electromechanical devices that require physical contact between a target object and switch activator to make the contacts change state.

Rotary limit switches use physically-actuated levers to rotate a shaft and operate the contacts in a switch, making them change state. Most products feature a rugged design and are suitable for factory and/or industrial applications; however, because these switches contain mechanical parts, they wear over time. Typically, rotary limit switches are slower than noncontact, electrical devices such as proximity sensors and photoelectric sensors.