A level switch is a device that, installed on a tank or other container in which solids or liquids are stored, allows you to discriminate whether the height or level that the stored material or element reaches or exceeds a predetermined level. When this condition occurs, this device changes state and generates an action that prevents the level from continuing to rise.

The simplest example of a level switch is a toilet float, which interrupts the flow of water when the tank reaches a certain level.

Level switches, also known as "level sensor" or "level float" work with a reed switch contact and a magnetic float. With the movement of this float, the contact is opened or closed.

The switches detect the level of the liquid in the tanks at the point where they are installed, returning an ON/OFF contact at the output.

Fixed at a point in the tank, liquid level switches, are not influenced by waves and vibrations, and ensure better reliability and repeatability compared to other types of older level detectors, such as level buoys.

These are considered low power sensors, since they are not used directly to drive pumps that have high power and currents.

The level switches work at an approximate power of 20W, which produces the current necessary to activate a lamp or acoustic signals, in digital control systems (Arduino, microcontrollers, frequency converters) or to activate relays, PLCs and contactors to activate/deactivate water pumps, for example.