A level relay is a relay that controls the liquid level. It's a relay with electrical wiring inside. Using the conductivity of the liquid. When the liquid level reaches a certain height, the relay will operate to cut off the power supply. When the liquid level is lower than a certain position, the power supply is turned on to make the pump work. To achieve automatic control. Automatic control consists of sensors and control actuators. The sensor of the level controller is generally a wire. Use the conductivity of water. The conductivity of water is poor and the relay cannot be driven directly. So there's an electronic circuit that amplifies the current to push the relay to work. To simplify it this way! The line is divided into high and low three lines, the high is the water level overflow point, the free control of the water level height, the water level to this automatic stop, the low point is the automatic water point, the water level at this point automatically start the water device. The center line is the normal contact
