Photoelectric level sensor application –Water dispenser

- Apr 03, 2020-

The main purpose of installing a liquid level sensor in the water dispenser is to prevent the hot water tank from burning out. If the hot water tank is dry-burned, it will not only cause damage to the heating resistor, but also cause great safety problems.
There are many ways to detect the level. The simplest and most convenient way is to use two electrode rods directly in the tank. Mainly the air and water have different conductivity to measure the water level. The electrical conductivity of water is large and the resistance is small. When the contact is flooded with water, the circuit between the electrode core and the container shell is short-circuited. The electrode in the air has a low conductivity, so the circuit is not open. This method is easy to install, but after a long time of use, it will produce electrolytic substances, which will affect water quality and be harmful to human body.



The floating ball type liquid level sensor is also a measurement method of detection, usually two wires. When there is water, the reed switch is turned on and powered on; when there is no water, the internal magnet drives the reed switch to turn off and power off. The application is simple, but it has a low accuracy and low reliability. Usually, the floating ball is stuck, the scale causes the accuracy to deteriorate, and the liquid level cannot be detected.

The photoelectric liquid level sensor uses the principle of optical reflection to detect the liquid level. When there is no water, it receives all the light emitted by the emission tube, the sensor outputs a high voltage signal. When there is water, the light is refracted in the water and only a small amount of pipeline can be received, the sensor outputs a low voltage signal.


The photoelectric level sensor has high reliability and stability, and is easy to install. Usually the head is threaded and can be screwed directly on the container.

The photoelectric liquid level sensor has the characteristics of cheap price, high accuracy and high reliability. Because its working principle is the principle of optical reflection, it is not affected by liquid color, corrosiveness, pressure, magnetism, temperature, etc., because of the low-cost photoelectric level sensor, it can be widely used in washing machines to prevent leaks, beverage machines without drinks reminders, and pumps to prevent air Pumping, automotive battery coolant detection, printer ink shortage reminder, and high level anti-overflow protection and low level power outage protection in home appliances, medical equipment, automotive and other fields
The components inside the photoelectric liquid level sensor have been fixed by the photosensitive resin sealant. There are no moving parts inside, so it has high reliability, stable performance and long life, Please contact us if you are interested in.