Question 1

What is ultrasonic level sensor?

Accepted Answer

Ultrasonic level sensor is a monitoring instrument for measuring liquid height, tank height, and material position.

Ultrasonic level sensor can adopt two-wire, three-wire or four-wire technology.

The two-wire system is: power supply and signal output are shared.
The three-wire system is: the power supply circuit and the signal output circuit are independent. When using DC 24v power supply, a 3-core cable can be used, and the negative terminal of the power supply and the negative terminal of the signal output share a core wire.
The four-wire system is: when using AC 220v power supply, or when using DC 24v power supply, when the power supply circuit and the signal output circuit are required to be completely isolated, a 4-core cable should be used.
DC or AC power supply, 4~20mADC, high and low switch output.

More about Ultrasonic Level Sensing Technology.

Question 2

How does ultrasonic level measurement work?

Accepted Answer

The working principle of the ultrasonic liquid level sensor is:

Ultrasonic transducer (probe) emits high-frequency pulse sound waves, and the surface of the measured level (material) is reflected back. The reflected echo is received by the transducer and converted into an electrical signal. The propagation time of the sound wave is proportional to the distance from the sound wave to the surface of the object.

The relationship between the sound wave transmission distance S and the sound speed C and the sound transmission time T can be expressed by the formula: S=C×T/2.

Image Source： https://www.coulton.com/beginners_guide_to_ultrasonic_level_transmitters.html

The probe part emits ultrasonic waves, which are then reflected by the liquid surface. The probe part is received again. The distance from the probe to the liquid (object) surface is proportional to the elapsed time of the ultrasonic wave:
hb = CT2
Distance [m] = time × speed of sound/2 [m]
The temperature compensation formula of sound velocity:
Ambient sound velocity = 331.5 + 0.6 × temperature

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

Question 3

What is a liquid level sensor?

Accepted Answer

Liquid level sensor is a kind of measuring instrument used to measure the change of liquid level in the container. It can display the change of liquid level intuitively and linearly. Among them, the magnetic float level sensor is a kind of one that can display on-site and output analog signals. Kind of level gauge.

There are many types of level gauges. There are intuitive displays such as: glass plate level gauges, glass tube level gauges, etc. There are also magnetic float level gauges, float level gauges, radar level gauges, ultrasonic level gauges, Level gauges with electronic signals such as radio frequency admittance level gauges.

Read more about: 7 Level Senors for Tank Level Measurement

Question 4

Ultrasonic liquid level sensors vs Radar level sensors

Accepted Answer

Ultrasonic level gauge is a sensor that emits ultrasonic waves. The sound waves are reflected by the liquid surface and then received by the same sensor. They are converted into electrical signals by piezoelectric crystals or magnetostrictive devices. The time between the transmission and reception of the sound waves is calculated to calculate the sensor The distance to the surface of the liquid being measured.

Very short microwave pulses with very low energy emitted by the radar level gauge are transmitted and received through the antenna system. Radar waves travel at the speed of light. The running time can be converted into a level signal by electronic components.

The radar level gauge is more accurate than the ultrasonic level. And the ultrasonic level gauge is not accurate when measuring the liquid level that produces the foam. Because the ultrasonic wave is reflected back when it hits the foam, the measured level is higher than the actual level. So The radar level gauge is used for the liquid level that is prone to foam. The microwave used by the radar level gauge can pass through foam. So it can also be used for level measurement of liquids that are prone to foam.

https://www.drurylandetheatre.com/non-contacting-radar-level-measurement/

Extended reading: Radar Non Contact Water Level Sensor

Question 5

What is ultrasonic liquid level detector?

Accepted Answer

Ultrasonic liquid level detector is actually an ultrasonic sensor for liquid level detection.

Extended reading: Sludge Blanket Level Detector Appliactions

Question 6

What is ultrasonic liquid level sensor?

Accepted Answer

Ultrasonic liquid level sensor is a digital liquid level meter controlled by microprocessor. Ultrasonic pulses are emitted by sensors (transducers) during the measurement. The sound waves are picked up by the same sensor after being reflected off the surface of the liquid. Converted into electrical signals by piezoelectric crystals. And the distance between the sensor and the liquid surface to be measured is calculated from the time between the emission and reception of the sound wave. Because of the non-contact measurement. The measured medium is almost unlimited. It can be widely used to measure the height of various liquid and solid materials.

Question 7

How does ultrasonic water level sensor work?

Accepted Answer

The working principle of the ultrasonic water level sensor is that the ultrasonic transducer (probe) emits high-frequency pulsed sound waves when it encounters the water surface and is reflected and folded back. The reflected echoes are received by the transducer and converted into electrical signals. The propagation time of a sound wave is proportional to the distance from the sound wave to the surface of the water.

Ultrasonic water level sensor is often used for water level monitoring in sewage stations, fire water tanks, reservoirs, etc.

Read more about: Ultrasonic Level Sensors for Liquids Applications

Question 8

Can ultrasonic sensor detect liquid?

Accepted Answer

Yes, Ultrasonic sensors for liquid level monitoring are the most common applications.

Extended reading: Hydrostatic Level Measurement

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