Procurement Guide: Ultrasonic liquid level sensors

Ultrasonic liquid level sensors realize the non-contact continuous detection of liquid level.

Ultrasonic liquid level sensors echo sounding sensors for measuring liquid level. And converting it to an electrical signal to send to other instrumentation. Ultrasonic Level Transmitters & Ultrasonic Level Sensors can be used for Non-intrusive level detection of sealed tanks. It can be used for liquid level detection of unsealed tanks and open channels such as rivers.

Hope you can purchase Ultrasonic liquid level sensors at the best price after reading this Procurement Guide.

Featured Ultrasonic liquid level sensors

You can choose the appropriate Ultrasonic liquid level sensors according to your measurement requirements.

Used to seal tanks and fire tanks. For example CO2 tanks, Halon, FM200, Propane, Novec 1230 and any liquefied gas under pressure.

Portable Ultrasonic Liquid Level Indicator

Portable Ultrasonic Liquid Level Indicator allows you to conveniently detect the level of liquid available in a container /cylinder/pipe/tank. Ultrasonic principle, Non-contact.

Reference price: USD 1200-1800.00/pc

Used as a non-intrusive tank level gauge. For example Liquid ammonia, liquid chlorine, hydrochloric acid, bromine, chlorethylene, sulfuric acid, freon, and nitirc acid, etc.

HS-2000 Ultrasonic Tank Level Sensor-External Mounted

Reference price: USD 3700-6700.00/pc

HS-ULC Ultrasonic Level Switch-External Mounted

Reference price: USD 1200-2800.00/pc

HS-ULC-Pro Ultrasonic Non-contact Liquid Level Controller

Reference price: USD 4400-8955.00/pc

Used as an open-hole tank and open liquid level. Such as: fuel tank, open channel liquid level. River level, etc.

Extended reading: Guide to Ultrasonic Level Transmitters

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.

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.

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

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

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.

Extended reading: Radar Non Contact Water Level Sensor

Ultrasonic Level Sensor and Transmitter

The working principle of the ultrasonic level gauge is that the ultrasonic transducer (probe) emits high-frequency pulsed sound waves. When encountering the surface of the measured material (material), it is reflected and folded back, and the reflected echo is received by the transducer and converted into an electrical signal. The propagation time of a 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, the sound speed C and the sound transmission time T can be expressed by the formula: S=C×T/2.

Ultrasonic sensors are also ultrasonic transducers, that is, probes.

Ultrasonic sensors are mainly composed of piezoelectric wafers. It can both transmit and receive ultrasonic waves. Low-power ultrasonic probes are mostly used for detection. It has many different structures, which can be divided into straight probe (longitudinal wave), oblique probe (transverse wave), surface wave probe (surface wave), Lamb wave probe (Lamb wave), dual probe (one probe reflection, one probe reception) Wait.

Ultrasonic transmitter refers to an instrument that can convert liquid level detection signals into analog signals or other signals. For example, we can require the ultrasonic level transmitter to output a 4-20mA signal.

Extended reading: GWR Corrosive Liquid Chemical Level Sensor

Ultrasonic Level Sensor 4-20mA

4-20mA is the common output signal of ultrasonic level gauge. To be precise, it can be divided into 2-wire, 3-wire, and 4-wire.

Two-wire system: The two-wire ultrasonic level meter shares a loop for power supply (DC24V only) and signal output (DC4-20mA). Only two wires are used and it is the standard transmitter form. The downside is that the transmit power is weak. Not suitable for liquid level measurement with large fluctuations. When the liquid level has a large volatilization. Measurements are also not ideal.

Three-wire system: The three-wire ultrasonic level gauge is actually a four-wire system. Its power supply (only DC24V) is separated from the signal output (DC4-20mA) loop. Use two lines each. When their negative terminals are connected in common, three wires are usually sufficient. The advantage is that the transmit power is larger. Suitable for liquid level and material level measurement in a variety of conditions. The effect is better.

Four-wire system: The power supply (DC24V or AC220V) is separated from the signal output (DC4-20mA) loop. The advantage of using two wires each is that the transmit power is greater. At the same time, it provides high and low relay output, adding new functions.

Extended reading: Non-Contact Level Measurement

Ultrasonic Level Sensor for Solids

In theory, ultrasonic liquid level sensors can be used to detect solid material levels. However, the general range should be reduced. The particles are uniform and the thickness is moderate. For example, corn, sand, detection is still very good. But the range is almost halved. If the particles are too fine, such as flour, cement powder will not work well.

Some ultrasonic level gauges can detect solids and liquids. For example, VEGA’s ultrasonic level meter does not distinguish between solid and liquid models.

And some brands of ultrasonic level gauges can only measure liquids, such as Siemens ultrasonic level gauges. It distinguishes the models that measure liquids and the models that measure solids. There are also models that can measure solid liquids.

Extended reading: Magnetostrictive Level Transmitter Advantages And Disadvantages

Laser level transmitter for solids

Non Invasive Level Measurement

Non Invasive Level Measurement means that the liquid level sensor is attached to the outside of the tank to detect the liquid level. In this way, there is no need to perforate the tank. Installation and monitoring are very convenient.

At present, the most commonly used Non Invasive Level Measurement is the ultrasonic sensor.

Non Intrusive Level Gauge

In addition to the Non Intrusive Level sensors at the top of this article. We also have a Non Intrusive Level Gauge. This externally mounted ultrasonic level sensor is mostly used for truck fuel tank level monitoring. Of course, it can also be used for other tank level monitoring according to the parameters.

Ultrasonic oil level sensor uses the principle of ultrasonic detection to detect the fuel level of the fuel tank. The fuel volume data is transmitted to the background monitoring system to achieve real-time monitoring of vehicle fuel consumption. Ultrasonic oil level sensor is mainly used in the field of Internet of Vehicles to monitor the change of fuel level in the fuel tank in real-time to achieve fuel level detection. It can be used to prevent fuel stealing, optimize operating costs, optimize driver driving behavior, and assist statistical decision-making. At the same time, this product can also be used in chemical, water conservancy, storage tanks, and other fields that require level detection.

Read more about Application 2: Tank Level Monitoring In The Oil And Gas Industry.

More Non Contact Liquid Level Sensors


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

Extended reading: Sludge Blanket Level Detector Appliactions

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.

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

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

Extended reading: Hydrostatic Level Measurement

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Sino-Inst offers over 10 Ultrasonic liquid Level Sensing sensors and transmitters for level measurement. About 50% of these are float liquid level meters, 40% is the level switches.

A wide variety of Ultrasonic Level Sensing sensors and transmitters options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Ultrasonic Level Sensing sensors and transmitters instrumentation, located in China.

This entry was posted in Level Measurement Solutions, Blog by KimGuo11. Bookmark the permalink.

About KimGuo11

Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects. Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.

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