Level switches transmit information when the level reaches a predetermined height. The system controls the process based on the information.
Conductance-based conductive level switches measure resistance when submerged in liquid. They are used in the case of conductive fluids. At most, one conductive electrode provides four different limit messages. Applications include dry operation protection, overfilling prevention, on/off level control.
Level switches are also available for magnet-mediated level indicators, in which case local indication is supplemented by limit data.
A float switch is a conventional, rather affordable method for on/off level measurement. Float switch models are manufactured for installation both from above and from the sides. Vertical models are available with several limit messages.