Ultrasonic liquid level sensors are mostly used in industry because of the working principle. Ultrasonic liquid level sensors have a blind zone. Because of the large size, this type level sensor cannot be used in small and medium-sized home appliances. If it is industrially used for measuring sewage, it can use ultrasonic liquid level sensor. Ultrasonic liquid level sensor has real-time detection characteristics, so it is applied to industrial large tanks and pools etc. Ultrasonic working principle level sensor is more suitable.
The electrode type liquid level sensor usually measure the liquid level change by the conductivity of liquid. The disadvantage of this type level sensor is that the electrolytic substance will be generated after a period of use, which is harmful to the human body. Electrode type liquid level sensors is not suitble for water dispenser, water purifier and etc.
Float level sensor, photoelectric level sensor and capacitive level sensor are all very common on the market. These level sensor are used in water dispensers, water heaters, water purifiers, coffee machines, electric steamers, toilet tanks. These three level sensors are smaller than other level sensors.
The oil level float switch and the capacitive liquid level sensor are susceptible to external factors, while the photoelectric type liquid level sensor is not affected by pressure, temperature and corrosiveness. Compared the two types of liquid level sensors, the reliabilty of optical type is higher, the life is more long.
The oil level float switch has a low precision, and the application environment is limited. Liquids such as sticky and debris can cause the float to become stuck and unable to move. Corrosive liquids can corrode plastic floats, stainless steel oil level float switch can increase costs. Therefore, although the oil level float switch has a simple working principle and a simple operation, the later maintenance is complicated.
Capacitive liquid level sensor is used to judge the change of liquid level according to the change of capacitance. Therefore, it can only detect the liquid level in the non-metallic material container, because metal may cause capacitance change, which may lead to misjudgment. The wall thickness of the container is also limited. Capacitive level sensors are non-contact detection, so the installation way is simple, the tank need not be any changed.
The photoelectric point level sensor uses the refraction and reflection of infrared light to distinguish the change of the liquid level. The structure is simple, the precision is high, and there is no mechanical part inside, so the reliability is high. The advantages are small volume, high sensitivity, low power consumption, no debugging, no calibration, no maintenance, corrosion resistance, high pressure resistance, high temperature resistance, etc.