The Hall-effect vane switch HKZ 121 is a contactless switch consisting of a monolithic integrated Hall-effect circuit and a special magnetic circuit hermetically sealed in a plastic package. The switch is actuated by a soft-iron vane which is passed through the air gap between magnet and Hall sensor. The main application field is in cars, i.e. as a breakerless trigger in electronic ignition systems. Numerous industrial applications can be found in control engineering, especially in those areas where switches must operate maintenance-free under harsh environmental conditions (e.g. rpm sensor, limit switch, position sensor, speed measurement, shaft encoder, scanning of coding disks, etc.).