What is an Ultrasonic Level Sensor?


Ultrasonic level sensors work by sending sound waves that echo off of a target and return to the transmitter. The term 'ultrasonic' means 'above human hearing', and refers to any sound wave above 20 kHz. An ultrasonic sensor works by sending those high-frequency sound waves to echo off a target and return to the level transmitters. Because the speed of sound is a constant -- under fixed atmospheric conditions -- the time from the sound burst to the return echo can be measured and translated into the distance traveled by the waves. By sending out ultrasonic sound waves, an ultrasonic level sensor is able to provide accurate, non-contact continuous level measurements.


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What is an Ultrasonic Level Sensor?

Each of our ultrasonic sensors has an onboard microprocessor, which allows for more advanced control. The ultrasonic level sensor’s microprocessor calculates the distance to the target surface and converts it to a level indication, a volume measurement, or a rate of flow. The microprocessor also compensates for temperature and filters the signal. This method is quite accurate, and we’ve developed a line of sensors with an accuracy of 0.25% of the detected range.

Common Uses of Ultrasonic Level Sensors

Ultrasonic level sensors are commonly used to measure distance or level, volume, and are used in flow monitoring. Other uses of an ultrasonic sensor include presence or absence detection, and object dimensioning.

Why Ultrasonic Level Sensors Need a Clear View of the Target

Ultrasonic sensors require an unobstructed air column between the sensor and the target. Because sound waves are physical waves, anything that deflects or absorbs the signal waves, or acts as a false surface, will cause erroneous readings. These can result from physical obstructions, excessive foam, heavy vapors, thick dust, or light powders between the sensor and the target surface.

Guiding Ultrasonic Waves

A waveguide can be used to contain or guide the signal around obstructions, and stilling wells can block out surface foam or waves. A more powerful sensor can also be used to strengthen the signal. However, our continuous float level transmitters, radar level transmitters, submersible pressure transducers, or level switches may be best in these scenarios.

Advantages of an Ultrasonic Level Sensors

An ultrasonic level sensor is typically quite small, low maintenance, and easy to ship and install. In addition, ultrasonic sensors do not come in contact with the target substance, which avoids build-up and damage to the sensor. All of these advantages, and many more, combine to create a product that will be sure to help you get the job done. Find the ultrasonic level sensor that’s right for you today.

blue ultrasonic level sensor from APG