Liquid Level Control Sensor

- Apr 26, 2020-

A sensor that can realize liquid level control can also be named to as a liquid level sensor, which refers to a mechanical or electronic method for controlling the level of liquid. It can control solenoid valves or water pumps to achieve semi-automatic or fully automatic. There are many methods, depending on the choice of different products.

The photoelectric liquid level sensor uses the principle of optical refraction to detect the liquid level. It is a common physical phenomenon that light refracts when it contacts with water, and the photoelectric liquid level sensor uses this phenomenon to distinguish between the water state and the waterless state, which is converted into a voltage signal output.

There is a launch tube inside the photoelectric liquid level sensor that emits light. When the sensor is in the water state, the light will be refracted in the water; when it is in the waterless state, it will not be refracted.

Compared to the original mechanical floating ball type liquid level sensor, its reliability, accuracy and stability can be maintained in a higher range. It has the characteristics of high precision, high reliability and long life.

The liquid level sensor cooperates with the controller to achieve liquid level control. When the measured liquid reaches the sensor position, the chip outputs a high-level or low-level signal, and then cooperates with the controller to control the liquid level. Then when the liquid level drops to the bottom without liquid, the sensor can provide a water shortage reminder after giving the signal, or drive the pump to add water. When the liquid level rises to the set position, after the sensor detects it can realize the full water reminder and control the pump to stop working.


The advantage of the photoelectric liquid level sensor is that it has no mechanical parts. It is not afraid of the influence of temperature and humidity. It can be installed at any angle. It is suitable for home appliances and medical equipment. The working voltage is 5-24V DC, which is very safe.