float switch is a type of level sensor a device used to detect the level of liquid within a tank. The switch may be used to control a pump as an indicator an alarm or to control other devices one type of float switch uses a mercury switch inside a hinged float. how does a float switch works float switch is a type of level sensor a device used to detect the level of liquid within a tank one pattern uses a reed switch mounted in a tube a float containing a magnet surrounds the tube and is guided by it when the float raises the magnet to the reed switch it closes. THANK`S FOR WATCHING...... Music in this video: A Magical Journey Through Space by Leonell Cassio Creative Commons — Attribution-ShareAlike 3.0 Unported — CC BY-SA 3.0 Free Download / Stream: Music promoted by Audio Library