Gikfun Wired Liquid Water Level Sensor Float Switch for Arduino EK1373

How it works: liquid level sensor magnetic reed switch by having an important and integral float, float within the magnetic material in a sealed non-magnetic metal pipe or plastic pipe set one or more magnetic reed switch, and then the catheter through a or more with magnetic float, and double-loop control using a fixed float and reed switch in the relevant position, the float rises or falls with the liquid using the ball close to the beginning of the reed contacts, resulting in open and shut action for level control or direction (when the float near the reed switch is turned on; leave the switch off)