This Siemens 3SX3 218 actuator is 28 mm in length and is suitable for use in plant and building automation systems. This actuator is compatible with Siemens 3SE2 series limit switches for use in interlock circuit applications.

Mechanical limit switches are used to make or break electrical circuit connections as part of a facility automation system. The switch is composed of a contact block with one or more electrical contacts, wiring connections, an enclosure for protection, and an actuator head for tracking object movement. Switch contacts can be normally open or normally closed, and switch connections can be either quick or slow, depending on the switch design, and they can include status LEDs and connector sockets. Actuator head types include rounded and roller plungers, roller and angular roller levers, spring rods, twist levers and rod actuators with a twist actuator, and fork levers with a twist actuator. Mechanical limit switches are used in many applications such as elevators, conveyors, doors, water tanks, railroad crossings, emergency exits, and as emergency shutoffs in industrial workplaces.

Siemens manufactures electronic products for building automation, industrial drives, lighting, energy generation, medical equipment, and rail transportation. The company, founded in 1847 and headquartered in Germany, meets International Standards Organization (ISO) standards 14001, 9001 and TS 16949.