A level sensor monitors, maintains and measures liquid and solid levels. Once the sensor detects the liquid level, it converts the perceived data into an electric signal. Level sensors are primarily used in the manufacturing and automotive industries but can also be found in many household appliances, such as ice makers in refrigerators.
Level sensors are categorized into two main types: point-level sensors and continuous-level sensors. Point level sensors indicate when a liquid reaches a specific point in a vessel, while continuous level sensors provide accurate measurements. Moreover, level sensors can be further divided into invasive and non-contact sensors. Invasive sensors directly contact the substance. Non-contact sensors use sound or microwaves and do not contact the substance.
There are several types of point level sensors available in the market, but all of them are invasive. One of the most basic types of point level sensors is the “float switch.” When the liquid level rises or falls in a container, it forces the switch to open or close a circuit. Optical level sensors comprise an infrared (IR) emitter and a photodiode that detect the presence of liquid by measuring the amount of infrared light reflected into the photodiode. Capacitance level sensors measure the change in capacitance, which is the ability to store electric charge, to determine tank liquid levels. “Tuning fork” sensors use differences in pressure and vibration to measure the liquid level.
Continuous level sensors are of two main types: ultrasonic and microwave. Unlike point level sensors, both of these are non-contact. Ultrasonic sensors emit sound waves, while “radar” sensors emit microwaves. The liquid level can be measured by the time interval between wave emission and reflection.
Conclusion:
A level sensor is a device used to measure the level of liquids, solids, or slurries within a container or in natural environments. It provides critical data that helps manage and monitor material levels for various industrial, environmental, and commercial applications. Level sensors come in different types, each suited to specific needs and environments. Common types include float-type sensors, which use a buoyant float to detect liquid levels; capacitive sensors, which measure changes in capacitance caused by the proximity of a material; and ultrasonic sensors, which use sound waves to detect the distance to the material’s surface. These sensors play a crucial role in ensuring efficient, safe, and economical operations across various industries, from water treatment to manufacturing and beyond.