Amazing Solutions for Continuous Liquid Level Measurement

Looking for a specific type or a custom continuous liquid level sensor? Sino-Inst offers High quality Liquid level sensors for continuous level measurement.

Continuous Liquid Level Measurement Solutions

Level sensors are used in process control in many industries and they fall into two categories. Continuous level measurement sensors and Point level measurement sensors.

The point level measurement sensor is used to indicate a single discrete level, that is, to indicate a preset level. The function of this type of sensor is the upper limit alarm, which indicates the overfill condition, or the lower limit alarm condition.

Continuous level sensors are more complex, allowing level monitoring of the entire system. They measure the level of the liquid level in a range, not the level of a point. Continuous level sensors produce an analog output that is directly related to the liquid level in the container. To build a level measurement system, this output signal is transmitted to the process control loop and visual indicators.

Sino-Inst offers a variety of Level senors for Continuous level measurement. If you have any questions, please contact our sales engineers.

Featured Continuous Level Sensors


SI-LT Magnetostrictive level transmitter with Local Digital Display
SI-100 Magnetostrictive Level Sensor
SI-U02 Multi-Point Liquid Level Float Switch

SI-U01 Float Level Sensor
ULT-200 Ultrasonic Level Detector
ULT-100A Ultrasonic Level Transducer
SMT3151TR Submersible Level Transmitter–2Mpa,200m
SI-80 Radar Level Sensors
SIRD90 Radar Level Transmitters, Non-Contact

SIRD70 Guided Wave Radar (GWR) Level Transmitters
RF Capacitance Level Transmitter

What is a Continuous Liquid Level Sensor?

Continuous level sensor definition

Continuous level sensors are transmitters that measure liquids within a specified range. Level sensors determine the exact amount of liquid that provides a continuous analog signal. The level signal can be displayed directly on site or integrated into a process control or management system. These products can be installed vertically and horizontally. They are ideal for monitoring liquids in confined or restricted areas.

Wikipedia: Level sensor

Difference between a point level sensor and a continuous level sensor?

Point level sensor

A sensor designed for point detection will detect liquid at a certain point in the tank or chamber. Generally, this applies to processes that require high-level or low-level management.

In most cases, they act as switches when the tank level rises or falls to a certain level. This could be an alarm or a bonding device. Essentially, the sensor detects when the liquid has reached the desired point, and it acts as a switch to activate the necessary response.

Continuous level sensor

The continuous level sensor is designed to detect the level through every point in the tank or chamber. This means that it provides feedback regardless of the level and the entire container range. This is great for processes where level is always important, and for applications that require increased accuracy.

Read more about: Ultrasonic Level Sensors for Liquids Applications

Extended Reading: How to Measure Volume of Liquid

A point level sensor is a device that can detect the presence or absence of almost any liquid medium. Typically, these sensors are used in processes that need to detect high or low levels.

Generally, common applications requiring point sensors fall into two categories:
Leak detection – to prevent costly damage or service interruption to equipment or level measurement – to prevent spillage or dry conditions.

The technology works like a switch. When the level of a tank or container reaches or falls below a certain threshold. It drives an action.

A wide range of point level sensors are available for many applications and materials.

The float level sensor is a common point level sensor.
The float level switch consists of a fixed rod and a float.
The float has a built-in permanent magnet, which moves freely along the fixed rod with the rise and fall of the liquid level. The magnetic field of the permanent magnet acts on the reed switch, and the closer it is to the reed switch, the stronger the force. When the threshold is reached, the reed switch is closed.
The float level sensor has a robust structure and a measurement deviation of less than 1%.

For point level detection applications requiring no moving parts. Optical liquid level sensors are a good option.
Optical liquid level sensors are suitable for high, medium and low liquid level detection. and fits almost any installation. It has no moving parts, emits infrared light through LEDs, and calculates liquid level changes based on the amount of reflected light.
Optical level sensors are available in custom high temperature models and in different sizes to meet the needs of different applications.

Capacitive level sensors are suitable for reflective, viscous or viscous fluids. According to their principle, capacitive sensors enable non-invasive measurements. Internal level changes can be measured without drilling holes in the vessel under test.

Ultrasonic liquid level sensors work by emitting and measuring reflected high-frequency sound waves, which can withstand high pressure, high temperature and vibration. It is suitable for measuring liquids without foam and air bubbles. Ideal for applications in agriculture, mining, construction, printing, and specialty vehicles.

Extended reading: How does a Radar Corrosive Liquid Chemical Level Sensor work?

Continuous level sensor 4-20 ma

Sino-Inst provides signal output for all continuous level sensors. Analog signal output, 4-20mA output, 0-5V, RS485, HART optional.

Advantages of current signal (4 ~ 20mA signal)

  1. The current signal is suitable for long-distance transmission. Because the current signal is not affected by the resistance of the wire. And the voltage signal will be divided when the wire itself has resistance, resulting in inaccurate measurement. Generally, the maximum transmission distance of 4 ~ 20mA is controlled within 100m, and it is recommended to use digital signals (485 communication)
  2. The current signal generally uses a two-wire system, and the voltage signal generally uses a three-wire system. In contrast, the two-wire system saves materials and reduces costs than the three-wire system.
  3. Compared with the on-site working conditions, the anti-interference ability of the current signal is stronger than the voltage signal. In the case of interference, it is recommended that the user select a 4 ~ 20mA signal.
  4. The current signal can appropriately exceed the range of the range and output inaccurate signals. For example, a pressure transmitter with a range of 1MPa and an output of 4-20mA can output 24mA when it exceeds the range. The voltage signal is slightly different depending on the power supply. For example, a pressure transmitter with a range of 1 MPa and an output of 0 to 10 V cannot output signals above 9 V when the power supply is 9 V.
  5. When the wire materials are not the same (such as copper, nickel), a magnetic field will generally be generated. And the voltage signal will have an error, and the current signal will not be required in the case of higher accuracy requirements.

Continuous Level Sensor can also be used with paperless recorder.

Measuring techniques for continuous level measurement

1. Ultrasonic Level Sensors

Ultrasonic Level Transmitters provide non-contact and maintenance-free level measurement, (Like the Radar ) for fluids, pastes, sludges and powdery to coarse bulk materials.

Ultrasonic level measurement, easy installation, wireless, portable and can be explosion-proof.Sonic is the sound we can hear. Ultrasonic is the sound above the human hearing range.

A human can hear maximum up to a frequency of 20 KHz. Ultrasonic frequencies are above 20 KHz. Ultrasonic waves are used to measure the level of liquids and solid objects in industries.

Ultrasonic level measurement is the contactless principle and most suitable for level measurements of hot, corrosive and boiling liquids.

The normal frequency range used for ultrasonic level measurements is within a range of 40-200 KHz.

Extended reading: Ultrasonic liquid level sensors

2. Hydrostatic (Pressure) Level Transmitters

Hydrostatic level transmitters, also called submersible level transmitter, or pressure level transmitters. For Hydrostatic level measurement, Continuous level measurement in liquid applications with pressure sensors. These transmitters help in determining fluid level of a container. By measuring the pressure of resting body of the fluid within it.

3. Continuous Level Radar Sensors

Radar level transmitter, also called Radar level gauge. Non-contact Continuous level measurement in liquids and solids with free space radar sensors

Non-contacting radar, based on microwave technology, detects only surfaces that reflect energy. These transmitters work on the principle of radar by using radio wave emissions. Mounted at the top of a tank filled with a liquid.

The transmitter sends a radar signal into the liquid and receives a reflection of the signal. The transmitters then analyze the current fill level of the tank based on the time taken by the transmitted signal to return.

Extended reading: Radar Liquid Level Sensor|Corrosive, steam, volatile liquids

4. Guided Wave Radar Level Sensors

Guided Wave Radar (GWR) Level Transmitters, also called wave guided radar level transmitter. Using guided wave radar technology, GWR level transmittershave no moving parts. They can measure both level and the interface between two media.

Continuous level measurement in liquids and solids with guided wave radar sensors. These transmitters work by sending a microwave pulse through a sensor cable or rod. The signal hits the surface of the liquid, and travels back to the sensor, and then to the transmitter housing.

Based on the time taken by the signal to travel down the sensor and back up again. The electronics integrated in the transmitter housing determine the filling level.

Extended Reading: Silo/Bin material level measurement system

5. Capacitance level detectors

Capacitance level detectors, also known as Capacitance level transmitter. RF Capacitance Level Transmitter offers continuous and point level detection. In liquids and solids with capacitance probes.

These transmitters use liquid stored in a tank or container as a dielectric medium between two or more electrodes. The energy capacity of the capacitor circuit increases when there is more liquid, and decreases if there is less liquid. Measuring the variations in the capacitance value, capacitance level transmitters calculate level of the tank.

Read more about: Capacitive Level Measurement Principle.

6. Magnetostrictive level transmitter

Magnetostrictive level transmitter, in-tank liquid level transmitter, is a continuous magnetic level gauge. The magnetostrictive level sensor, measure the level of fluid in the vessel.

By detecting the level of the magnets contained within the float and then transmits the measurement back to the control system.

7. Magnetic Float level sensors

Magnetic Float level sensors are continuous level sensors featuring a magnetic float that rises and falls as liquid levels change.

The movement of the float creates a magnetic field that actuates a hermetically sealed reed switch located in the stem of the level sensor, triggering the switch to open or close.

Comparative analysis – 7 Tank Level Measurement Sensors

Applications

Continuous level sensors are versatile in monitoring liquid level needs. They can monitor water, diesel, lube oils and fuels, as well as various chemical and petrochemical liquids. And compatible with corrosive and non-corrosive substances.

Continuous level sensors are and used by industries including:

  • Food and Beverage
  • HVAC
  • Medical
  • Printing
  • Off-Highway Vehicles
  • Semiconductor
  • Oil and Gas
  • Agriculture
  • Wastewater Treatment
  • Concrete/Aggregate
  • Plastic/Vinyl
  • Marine
  • Chemical

Extended reading: Sludge Blanket Level Detector Appliactions

The Silo/Bin level measurement and control system solves the problem of frequent dumping accidents in the powder silo of the mixing station during the feeding process. It avoids the problems of dust flying, waste of cement, and environmental pollution. It reduces the equipment damage caused by the collapse of the dust removal hood of the mixing station Other issues and prevents the safety issues of the workers present.

Extended Reading: Silo/Bin material level measurement system

Generally, we can use radar level sensors, ultrasonic, or guided wave radar to measure.

Tank level senor is a level sensor used to measure the tank level. The liquid level is the level of the liquid in a sealed container (such as a water tank) or an open container (water tank). The instrument that measures the liquid level is called a liquid level sensor, a liquid level gauge or a liquid level transmitter. The liquid level sensor is a kind of level instrument. Hydrostatic, Ultrasonic, Magnetostrictive, Radar, Differential Pressure are commonly choices for tank level measurement. Liquid level sensors have been around for decades for leak detection or level measurement. Common measured medium are: Water, Fuel, Diesel, Gasoline, diesel, liquefied gas, liquid ammonia, etc.

Read more about: Level Senors for Tank Level Measurement

To measure the powder level, most of the radar level gauges and ultrasonics are used. Or heavy hammer level gauge.

High-frequency radar level gauge application: powdery solids, or environments with a lot of dust
① coal bunker, cement bunker, clinker bunker,
② Flour, corn flour, rice flour, sorghum flour, etc.
③Iron powder, aluminum powder, etc.

Ultrasonic level meter (ultrasonic level sensor) is used to measure the level of solid materials such as coal, ore, corn, wheat, glass, straw, garbage, wooden boards, automobiles, plastic particles, etc. It is used in metallurgy, mining, grain processing, storage, security and other industries.

Extended reading: Non Contact Liquid Level Sensor Working Principle

A laser level transmitter is also called a laser level meter. Industrial Accurate, non-contact, and uninterrupted real-time monitoring of material height. Designed for material level and liquid level. A laser level transmitter is a continuous or high-speed pulsed laser beam emitted by a semiconductor laser.

The laser beam meets the surface of the object to be measured and reflects. The light return is received by the laser receiver. And accurately record the time difference between laser emission and reception. In order to determine the distance from the laser radar to the measured object. Laser level transmitter is similar to radar/ultrasonic level sensor.

Read more about: Laser Level Transmitter

There are many types of liquid level sensors that can measure water. From our personal experience, hydrostatic submersible level sensors are the easiest to use and relatively low cost.

Extended reading: Hydrostatic Level Measurement

But,

Sometimes, due to the limitation of measurement conditions, it is necessary to select the external water tank level indicator.
Our Sino-inst external water tank level indicator is based on ultrasonic principle.
When measuring with External Tank Level Indicator, install the ultrasonic probe just below the outer wall (bottom) of the container under test. No need to cut holes, easy to install. Does not affect on-site production. It can realize accurate measurement of various toxic substances and various pure liquids in high temperature and high pressure airtight containers.

Read more about: External Tank Level Indicator

How to select a continuous level sensor?

Selection of level measurement sensor.

Issues to consider before selecting a level measurement sensor include:

  1. Measure liquid or solid?
  2. What is the temperature and pressure range of the application environment?
  3. Need point level measurement or continuous measurement?
  4. What is the level measurement range required?
  5. Is the measured material conductive?
  6. Will the measured material cover or accumulate on the surface?
  7. Will there be turbulence, foam or steam on the liquid surface?
  8. Do you need contact or non-contact level measurement?
  9. What kind of output is required, analog, relay, digital display or other?

Frequently
Asked
Questions

In continuous level measurement, the level of a medium in a tank or silo is detected with the help of different measuring methods and converted into an electronic signal. 

Continuous level sensors are more complex, allowing level monitoring of the entire system. They measure the level of the liquid level in a range, not the level of a point, and therefore produce an analog output that is directly related to the liquid level in the container. To build a level measurement system, this output signal is transmitted to the process control loop and visual indicators.

There are 7 main types of level transmitters that Sino-Instrument offers. Each type of transmitter works in a different way, and makes it useful for different types of processes.

The point level measurement sensor is used to indicate a single discrete level, that is, to indicate a preset level. Normally, the function of this type of sensor is the upper limit alarm, which indicates the overfill condition, or the lower limit alarm condition.

What are the common types of oil level sensors?

  • Magnetic float sensor: Developed according to the principle of buoyancy and magnetic coupling, with good visibility of characteristics and direct reading of values;
  • Pressure sensor: Use liquid pressure to measure liquid depth, suitable for measuring water depth in river channels;
  • Capacitive sensor: Utilize the principle that the capacitance formed between the probe and the container changes linearly with the liquid (material) level. There is no moving or elastic component. Impact resistance, easy installation, high accuracy, high reliability;
  • Magnetostrictive sensor: The principle of the sensor is to generate a longitudinal magnetic field through a permanent magnet and another magnetic field through an electric current. When the two magnetic fields intersect the waveguide, the waveguide generates a “magnetostrictive” phenomenon, and a strain pulse is generated instantly. Features It is fast and accurate. It is mostly used for liquid measurement in tank trucks;
  • Float sensor (reed switch): It is more common. Nowadays, the automatic oil level sensors of automobiles belong to this category. The working principle is to use the buoyancy of liquid on magnetic floating ball, and the dry spring of floating ball level gauge is magnetically attracted to change the liquid level position into an electrical signal. The reed switch is connected in sections, and the length of each section is the test accuracy of the level gauge.

The working principle of the oil level sensor device is through the continuous acquisition of the relative percentage signal of the oil level sensor. With the calibration algorithm, it is converted into the corresponding volume information. The fuel quantity of the fuel tank is monitored. Combined with the GPS system, the vehicle is known Driving status.

Point-level switches are used as high-level and spill-prevention alarms, low-level and pump-protection alarms, and to turn pumps on and off. Continuous level (proportional) measurement, on the other hand, indicates the level in a vessel over the full span of measurement.

Point level measurement is different from Continuous Level Measurement. Used to detect material levels in tanks or silos.

There are high levels (with material) and low levels (without material).

High level measurement allows containers to be filled to full capacity while preventing overflow situations.

Low level measurement alerts facilities to the need for replenishment, preventing process and/or plant downtime.

Technical Support

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What is Point Level Measurement? Point Level Measurement refers to the use of a point level sensor to detect the material level in a storage tank or silo. Also called…

Sino-Inst offers over 40 Continuous Level Measurement Sensors. About 50% of these are liquid level meters, 40% is the tank level sensor.
A wide variety of Continuous Level Measurement Sensors options are available to you, such as free samples, paid samples.
Sino-Inst is a globally recognized supplier and manufacturer of Continuous Level Measurement Sensors instrumentation, located in China.

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The Secret of Ultrasonic Level Measurement

Ultrasonic level measurement is a contactless principle and is most suitable for level measurements of hot, corrosive, and boiling liquids.

Ultrasonic level measurement provides a Continuous level measurement in liquids and solids with ultrasonic level sensors。 Non-contact, and maintenance-free level measurement of fluids, pastes, sludges, and powdery to coarse bulk materials. The measurement is unaffected by dielectric constant, density, or humidity. And also unaffected by build-up due to the self-cleaning effect of the sensors.

If you need to measure liquid levels, an ultrasonic level sensor is a good choice.

In the article “Level Senors for Tank Level Measurement“, we introduced a variety of level sensors that can be used to measure the tank level. Here, we will introduce the ultrasonic level sensor in detail.

Featured Sensors for Ultrasonic Level Measurement:

Features of Ultrasonic liquid level sensors

Ultrasonic liquid level sensors are non-contact level measurement devices. In the measurement, the ultrasonic pulse is sent by the sensor (transducer). The sound wave is reflected by the liquid surface and received by the same sensor or ultrasonic receiver. It is converted into an electrical signal by a piezoelectric crystal or a magnetostrictive device. It is transmitted and received by the sound wave. The time between the sensor and the surface of the liquid is measured. Due to non-contact measurement, the measured medium is almost unlimited. It can be widely used for measuring the height of various liquid and solid materials. Like: water level, fuel level, oil level, petrol tank level, and so on.

  • Accurate and reliable sensing method
  • Ultrasonic level sensor technology is ideal for difficult fluids where contact with the media is not desirable 
  • An ultrasonic liquid level transmitter is ideally sized and priced for most applications
  • Easy to install– simple to use
  • There are no moving parts
  • Temperature-compensated signal for improved accuracy
  • Self-cleaning sensor face
  • Unaffected by the target material’s color, shape or physical composition
  • Bench- or field-calibrated through communications with a PC or a push button on the sensor
  • Non-contact measurement, high performance, low cost, maintenance-free, high precision, long life;
  • Intelligent signal processing technology, the instrument adapts to various working conditions;
  • Two-wire system, three-wire system, isolated four-wire system
  • 24VDC, 220VAC power supply optional
  • Over-voltage, over-current, lightning protection
  • Photoelectric isolation 4-20mA current output

Extended Reading: How to Measure Volume of Liquid

Advantages of Ultrasonic Level Transmitter

  1. No media contact for vertically mounted type, so flexibility for use on different corrosive media, thick fluids, slurries, wastewater
  2. Ultrasonic level transmitter has no moving parts. And it can measure level without making physical contact with the object.
  3. High temperature fluid compatibility for vertically mounted types, since no sensitive components make contact with the fluid
  4. High accuracy due to high frequency pulse wave and precise transit time time measurement
  5. The accuracy of the reading remains unaffected even after changes in the chemical composition or the dielectric constant of the materials in the process fluids.
  6. Operates with conductive or non-conductive fluids
  7. Sealed pressurised vessel will not affect performance
  8. Shorter blocking distance than radar
  9. Useful for measuring levels in tanks with corrosive, boiling and hazardous chemicals.

Disadvantages of Ultrasonic Level Transmitter

  1. Foaming, splashing, vapour and humidity can affect measurement performance
  2. High cost compared to other technologies
  3. Minimal blocking distance limits operation when in proximity to liquid level
  4. Temperature compensation required to compensate for speed of sound variation with air temperature
  5. Sound waves cannot be transmitted through a vacuum
  6. Shorter range than radar.
  7. It is not so convenient if the tank depth is high or the echo is absorbed or dispersed.
  8. The object should not be sound absorbing type.
  9. It is also unsuitable for tanks with too much smoke or high density moisture.

More about The Difference Between Ultrasonic Depth Sensor And Ultrasonic Level Sensor.

Extended reading: Guide to Ultrasonic Level Transmitters

What Is the Principle of Ultrasonic Level Measurement ?

Ultrasonic waves detect an object in the same way as Radar does it. Ultrasonic uses sound waves, and Radar uses radio waves. When the ultrasonic pulse signal is targeted towards an object, it is reflected by the object, and the echo returns to the sender.

The time traveled by the ultrasonic pulse is calculated, and the distance of the object is found.

Bats use a well-known method to measure the distance while traveling.

The ultrasonic level measurement principle is also used to find out fish positions in the ocean, locate submarines below water level, also the position of a scuba diver in the sea.

We will refer to Fig-1 and make an effort to understand the technicalities of the ultrasonic level transmitter.

An ultrasonic level transmitter is fixed at the top of a tank half filled with liquid.

The reference level for all measurements is the bottom of the tank.

The level to be detected is marked as “C”, and “B” is the distance of the ultrasonic sensor from the liquid level.

Ultrasonic pulse signals are transmitted from the transmitter, and it is reflected back to the sensor.

The travel time of the ultrasonic pulse from the sensor to the target and back is calculated.

Level “C” can be found by multiplying half of this time with the speed of sound in the air.

The measuring unit’s final result can be centimeters, feet, inches, etc.

Level = Speed of sound in air x Time delay / 2

Ultrasonic Level Measurement
TipYou can see our range of Ultrasonic Level Transmitters here.

Practical System Design Problems of Ultrasonic Level Transmitter:

The above principle of measurement looks quite straightforward and true only in theory.

In practice, there are some technical difficulties that are to be taken care of to get the correct level of reading.

  1. The velocity of sound changes due to the variation of air temperature.
    • An integrated temperature sensor is used to compensate for changes in the velocity of sound due to temperature variations.
  2. There are some interference echoes developed by the edges, welded joints, etc.
    • This is taken care of by the software of the transmitter and called interference echo suppression.
  3. Calibration of the transmitter is crucial.
    • Accuracy of measurement depends on the accuracy of the calibration.
    • The Empty distance “A” and measurement span “D” is to be ascertained correctly for inclusion in the calibration of the transmitter.
  4. The transient characteristics of the sensor will develop a Blocking distance as shown in Fig-1. Span “D” should never extend to the blocking distance.

The Basic Structure of an Ultrasonic Transducer:

structure of an Ultrasonic Transducer

An ultrasonic sensor is the heart of the ultrasonic level Transmitter instrument.

This sensor will translate electrical energy into ultrasound waves.

Piezoelectric crystals are used for this conversion process.

Piezoelectric crystals will oscillate at high frequencies when electric energy is applied to it.

The reverse is also true.

These piezoelectric crystals will generate electrical signals on receipt of ultrasound.

These sensors are capable of sending ultrasound to an object and receiving the echo developed by the object.

The echo is converted into electrical energy for onward processing by the control circuit.

Extended reading: GWR Corrosive Liquid Chemical Level Sensor

Functional Block Diagram of a Typical Ultrasonic Level Transmitter:

We will refer to Fig-3 Functional Block Diagram to clarify the physical structures of an Ultrasonic Level Transmitter.

A micro-controller-based Control Circuit monitors all the activities of the ultrasonic level transmitter.

There are two Pulse Transmission Circuits, one for transmitter pulse and the other one for receiver pulse.

The pulse generated by the transmitter pulse is converted to Ultrasound pulses, by the Ultrasonic Sensor(Transmitter) and targeted towards the object.

This ultrasound pulse is reflected back as an echo pulse to the Ultrasonic Sensor (Receiver). The receiver converts this Ultrasonic pulse to an electrical signal pulse through the pulse generator.

The time elapsed, or the reflection time is measured by the counter. This elapsed time has relation to the level to be measured. This elapsed time is converted to level by the Control Circuit. There is a Timing Generator Circuit which is used to synchronize all functions, in the ultrasonic level measurement system.

The level is finally converted to a 4-20mA signal. 4mA is 0% level, and 20mA is the 100% level (see Fig-1).

This 4-20mA output signal carrying the level data can be transmitted to long distance to Process Control Instruments.

Functional Block Diagram for clarify physical structures of an Ultrasonic Level Transmitter.

Common Applications for Ultrasonic Liquid Level Sensors

Ultrasonic liquid level sensors are used for liquid level, solid material level, the tank body, and open channel flow. Their performance is very good. Ultrasonic level sensors are also ideal for applications where continuous level measurement is required.

The most popular application of ultrasonic level sensors is to measure the level of liquid in tanks, wells, pits or lakes.If the container is linear, extrapolating the volume measurement is easy. In a non-linear container, a strapping table is usually used to adjust the reading to a certain volume as the level increases and decreases. Most of our ultrasounds are specifically designed for level measurement.Find the right sensor for you. Since ultrasonic sensors work without the need to touch the medium, they are ideal for difficult or corrosive liquids. Such as acids, wastewater, and others.

Read more about: Ultrasonic Level Sensors for Liquids Applications

Typical Media:

  • Acids
  • Wastewater
  • Inks and Paints
  • Slurries
  • Food and Beverage
  • Semiconductor Process Chemicals
  • Oils and Petroleum Distillates

Another very popular application of ultrasonic sensors is solid level detection. The trick is actually to use a sensor with twice the required distance. This gives you a stronger signal, which in turn provides a better echo for the sensor’s measurements. You may also need to tilt the sensor mount so that it is perpendicular to the angle of repose.
Measuring solids has always been difficult. But ultrasound will still be the main condition for continuous non-contact measurement.

Open channels are the main means of transporting, filtering, and metering water. Open channel flow monitoring is used in water treatment plants, environmental monitoring, and irrigation canals. Ultrasonic sensors are an excellent choice for open channel flow.

Extended reading: Case Study: Automatic Sludge Blanket Level Detector

Read more about: Top 5 Ultrasonic Level Sensor Applications

Liquid Level Measurement with Ultrasonic Sensors

Tank level sensor

Tank level senor is a level sensor used to measure the tank level. The liquid level is the level of the liquid in a sealed container (such as a water tank) or an open container (water tank). The instrument that measures the liquid level is called a liquid level sensor, a liquid level gauge or a liquid level transmitter. The liquid level sensor is a kind of level instrument. Hydrostatic, Ultrasonic, Magnetostrictive, Radar, Differential Pressure are commonly choices for tank level measurement. Liquid level sensors have been around for decades for leak detection or level measurement. Common measured medium are: Water, Fuel, Diesel, Gasoline, diesel, liquefied gas, liquid ammonia, etc.

Ultrasonic level sensor wastewater

The ultrasonic level gauge is widely used in water level meter measurement projects in: Water plants. Wastewater treatment plants. Chemical reagent plants. Dye factories. Pulp mills and other factories. And is one of the main level measurement methods in modern intelligent automation industry. Ultrasonic technology has been used in the wastewater industry for more than 30 years for its high cost performance. Level gauges are widely used in industrial wastewater treatment plants and municipal wastewater treatment plants. Ultrasonic level gauges have the most applications, but their installation and measurement are limited by space.

In addition, since the propagation time of sound waves is affected by temperature, the ultrasonic sensor must be equipped with a temperature sensor. Ultrasonic level gauges are more accurate when used indoors or at groundwater levels.

Outdoors, the ultrasonic sensor generates heat due to sunlight. This will lead to inaccurate compensation for the propagation time of the sound waves, which will cause measurement errors. In chemical plants, there are a lot of high-concentration gases over chemical liquids, which will also change the propagation time of sound waves and even absorb sound waves. The shortest distance that an ultrasonic sensor can measure is usually 10-50cm. When installing, consider the “blind zone” that cannot be measured.

Extended reading: Radar Liquid Level Sensor|Corrosive, steam, volatile liquids

Ultrasonic Level Sensor for Solids

Liquid level and material level measurement is a problem often encountered in the industry. Ultrasonic positioning technology has many advantages. It can not only locate and continuously locate but also conveniently provide the signals required by telemetry or remote control. Compared with radioactive positioning technology, ultrasonic technology does not require protection. Compared with laser-ranging technology, it has the advantages of simplicity and economy. At the same time, ultrasonic technology generally does not require moving parts, so it is relatively convenient to install and maintain. .The ultrasonic level meter can be widely used in: Petroleum, mining, power plants. Chemical plants, water treatment plants. Sewage treatment stations. Agricultural water. Environmental monitoring. Food (wine industry, beverage industry, additives, edible oil, dairy products). Flood resistance Flood control, hydrological monitoring. Open channels, spatial positioning, and many other industries. There are two main installation methods for ultrasonic level gauges, one is top installation and the other is bottom installation. The ultrasonic level gauge also uses liquid sound guidance. The ultrasonic probe is installed outside the bottom of the tank. The measuring liquid is transmitted to the liquid surface and then reflected back to the probe. The propagation time is directly proportional to the level of the liquid.

Common Questions for Level Measurement Applications:

Sino-Inst offers a variety of tank level measurement solutions. If you have any questions, please contact our sales engineers. CONTACT US

Sino-Inst’s Tank level sensors easily handle these liquids. Rugged construction. Corrosion resistant materials. A wide environmental operating range and a liquid-tight IP68 ingress rating make them ideal for indoor and outdoor use. Even in salt water and hydrogen sulfide (H2S) environments.
Products are offered in a variety of distance ranges to accommodate tanks. Ranging from 6 in (15 cm) to 50 feet (15.2m), with various mounting threads and accessories available.

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Ultrasonic level gauges work well outdoors. But we also need to protect the ultrasonic level gauge.

Ultrasonic level gauge outdoor requirements:
     1. It is recommended to install a sun visor to extend the service life of the meter.
     2. Wire and cable protection pipes should be sealed to prevent water accumulation.
     3. Although the instrument has its own lightning protection device, it is recommended to install a special lightning protection device at the inlet and outlet of the instrument when the instrument is used in a lightning-resistant area.
     4. The instrument is used in particularly hot and cold places, that is, when the ambient temperature may exceed the working requirements of the instrument, it is recommended to add high and low temperature devices around the level gauge.

Yes, Sino-Inst offer explosion-proof ultrasonic level sensors for Hazardous locations.

Explosion-proof ultrasonic level gauge has built-in temperature compensation, self-adaptive power. And can have signal processing technology, which improves the measurement accuracy of the instrument. It has obvious suppression function for interference echo. The explosion-proof ultrasonic level gauge uses a metal-aluminum alloy die-casting housing. Which has a beautiful appearance and good protection ability. The instrument uses industrial isolated power supply. And all input and output lines have lightning protection, overvoltage, and overcurrent protection circuits.Explosion-proof ultrasonic level gauge is suitable for measuring corrosive mud or sewage, hydrochloric acid, sulfuric acid, hydroxide and other corrosive media. Ultrasonic level gauge can be applied to process tanks, daily tanks, pools, etc. The position meter is mainly used in oilfield, chemical, power, metallurgy and other industries.

Ultrasonic level sensor is a digital level instrument controlled by a microprocessor. In the measurement, the pulsed ultrasonic wave is sent by the sensor (transducer). And the sound wave is reflected by the surface of the object and received by the same sensor, which is converted into an electrical signal. The distance between the sensor and the measured object is calculated from the time between the transmission and reception of the sound wave. Due to non-contact measurement, the measured medium is almost unlimited. And it can be widely used for measuring the height of various liquid and solid materials.

Sure. Ultrasonic liquid level sensors can detect water level. Like wastewater, in tank, in river.

Sino-Instrument offers over 10 level transmitters for level measurement.

About 50% of these are liquid level meters,

40% is the tank level sensor.

A wide variety of level meters options are available to you,

such as free samples, paid samples.

Sino-Instrument is a globally recognized supplier and manufacturer of level measurement instrumentation, located in China.

Request a Quote

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7 Type Tank Level Senors For Liquid and Solid

Sino-Inst produces many types of tank level sensors. Whatever your media, tank depth, and profile, Sino-Inst can always provide you with the right tank level sensors.

Tank Level Senors are also called Tank level indicators, tank level gauge, tank level meters, or tank level transmitters. Specifically refer to a type of sensor that can be used to measure tank level. The measured medium can be liquid or solid powder. Such as water, hydrochloric acid, Fuel, Diesel, Gasoline, liquefied gas, liquid ammonia, flour, cement, etc.

Featured Tanks Level Sensors

Tank Level Sensors Types:

Ultrasonic fuel tank level sensor, also called non-contact fuel meter. Ultrasonic level sensor measure continuous liquid level, fluid level, or oil level.

Ultrasonic level sensors measure the distance between the transducer and the surface. Using the time required for an ultrasound pulse to travel from a transducer to the fluid surface and back (TOF).  These sensors use frequencies in the tens of kilohertz range; transit times are ~6 ms/m.  The speed of sound (340 m/s in air at 15 degrees C, 1115 fps at 60 degrees F) depends on the mixture of gases in the headspace and their temperature.

Ultrasonic sensors work without the need to touch the medium being measured. Ultrasonic sensors are ideal for difficult or corrosive liquids such as acids, wastewater, and others. Ultrasonic level sensors are also ideal for continuous level measurement. While float switches and other sensors are adept at measuring when liquid levels are above or below a certain point. The nature of ultrasonic level measurement is such that levels can be sensed and displayed in real-time.

More about Ultrasonic level measurement

Features of Ultrasonic Tank Level Sensor

  • Non-contact – nothing touches the liquid
  • Easy to install at the top of the tank into standard fittings
  • Use indoors or outside, in metal or plastic tanks
  • Connects to other industrial equipment
  • Measures a wide variety of liquids and liquid environments
  • Accessories to display, alarm, and control liquid levels
  • Wireless option sends tank levels to a LAN or the cloud
  • MRO & OEM tank setup duplication without re-calibration

Read more about: Ultrasonic Tank Level Sensor-External Mounted

Magnetostrictive level transmitter, in-tank liquid level transmitter, is a continuous magnetic level gauge. The magnetostrictive level sensor measure the level of fluid in the vessel. By detecting the level of the magnets contained within the float and then transmits the measurement back to the control system.

Magnetostrictive liquid level transmitter is a kind of liquid level sensor. But it uses the principle of magnetostrictive operation internally. And combines modern electronic technology to measure the time value between pulse waves to achieve the purpose of accurately measuring the liquid level . The magnetostrictive liquid level meter works with waveguide pulses. During the work, the measured displacement is determined by measuring the time of the start pulse and the end pulse, so the measurement accuracy is high.

Features of Magnetostrictive Level Transmitters:

  • High Accuracy
  • High Reliability
  • No calibration required
  • No Maintenance
  • Simultaneous Measurement of Multiple Process Conditions:
    -Product Level
    -Interface Level
    -Temperature
    -Volume
  • No Scheduled Maintenance or Recalibration
  • Field Repairable
  • Inherent Accuracy ±0.039” (±1 mm)
  • 200 Point Strap Table
  • API Temperature Corrected Volumes
  • Integral Display
  • Hazardous Area Certified
  • Intrinsically Safe

More about Magnetostrictive liquid level tmeasurement

Submersible level sensor, Pressure and DP level transmitter are all hydrostatic measurement devices.

Also known as pressure level transmitters, these transmitters help in determining fluid contents of a container, by measuring the pressure of the resting body of the fluid within it. The greater the force of liquid, the greater the volume of fluid.

Extended reading: Hydrostatic Level Measurement

The pressure type liquid level gauge is a pressure sensor that measures the liquid level. Including static pressure level gauge, liquid level transmitter, pressure transmitter and so on. The measured static pressure of a liquid is proportional to the height of the liquid. And the static pressure is converted into an electrical signal. After temperature compensation and linear correction, it is converted into a standard electrical signal (4-20mA / 1 ~ 5VDC). Hydrostatic liquid level sensor is suitable for liquid level measurement of various media in systems and industries. Such as petrochemical, pharmaceutical, water supply and drainage, environmental protection and other systems. The exquisite structure, simple adjustment and flexible installation methods provide convenience to use.

Read more about: Submersible Level Transmitter-Straight Rod Insertion

The differential pressure level gauge is a meter that calculates the liquid level (differential pressure) in a tank. By measuring the pressure difference at two different points of the container. For example, a 500 mm water column corresponds to a pressure of 500 mmH20. In many applications, however, there is additional vapor pressure above the liquid. Vapor pressure is not part of the level measurement. So impulse tubes and capillaries with seals are needed to counteract its presence.Capillary columns and sealing systems solve many installation problems with impulse tubes. These systems include an external sensing diaphragm. This diaphgram connected to a differential pressure transmitter via an oil-filled capillary column. The change in pressure causes a displacement of the diaphragm. So that the pressure is transmitted to the transmitter through the oil-filled capillary. The oil-filled capillary system is carefully welded and manufactured. So it is a reliable sealing system. This type of structure eliminates leak points and blockages that may occur in the impulse tube.

More about Hydrostatic pressure level measurement

Radar level transmitter, also called Radar level gauge. Non-contact Continuous level measurement in liquids and solids with free space radar sensors. Non-contacting radar, based on microwave technology, detects only surfaces that reflect energy. These transmitters work on the principle of a radar by using radio wave emissions. Mounted at the top of a tank filled with a liquid. The transmitter sends a radar signal into the liquid, and receives a reflection of the signal. The transmitters then analyze the current fill level of the tank based on the time taken by the transmitted signal to return.

Operating Principle of Non-Contacting Radar Level Sensors/Gauges (Unguided Wave)

Extended reading: Radar Liquid Level Sensor|Corrosive, steam, volatile liquids

Radar Level Sensor Features

  • Non-contact, continuous level measurement over larger ranges
  • Unaffected by sludge and biomass, dust, foam, oil, grease and other coatings, uneven surfaces, turbulence, pressure, and vacuum
  • Single frequency radar level sensors for liquid sensing, dual frequency radar level sensors for level measurement of aggregates, gravel, sand, coal, asphalt, and other solids
  • Simple mounting and push-button calibration

More about Radar level measurement

Capacitance level detectors, also known as Capacitance level transmitter. RF Capacitance Level Transmitter offers continuous and point level detection. In liquids and solids with capacitance probes. These transmitters use liquid stored in a tank or container as a dielectric medium between two or more electrodes. The energy capacity of the capacitor circuit increases when there is more liquid, and decreases if there is less liquid. Measuring the variations in the capacitance value, capacitance level transmitters calculate level of the tank.

Features of SI700 RF capacitance level transmitter:

  • Capacitive level measurement enables measurement without blind spots over the entire sensor length
  • Fully insulated capacitive sensors also measure aggressive liquids
  • Cost-effective measurement for trouble-free and maintenance-free operation

More about capacitance level measurement

These gauges are the preferred replacement for the sight glasses. They are similar to float devices, but they communicate the liquid surface location magnetically.  The float, carrying a set of strong permanent magnets, rides in an auxiliary column (float chamber) attached to the vessel by means of two process connections.  This column confines the float laterally so that it is always close to the chamber’s side wall. As the float rides up and down the fluid level a magnetized shuttle or bar graph indication moves with it. Showing the position of the float and thereby providing the level indication.  The system can work only if the auxiliary column and chamber walls are made of non-magnetic material.    

Sino-Inst provides float designs optimized for the specific gravity of the fluid being measured. Whether butane, propane, oil, acid, water, or interfaces between two fluids, as well as a large selection of float materials. This means the gauges can handle high temperatures, high pressures and corrosives fluids. Oversized float chambers and high-buoyancy floats are available for applications where buildup is anticipated.

Chambers, flanges and process connections can be made from engineered plastics. such as Kynar or exotic alloys such as Hastelloy C-276.  Special chamber configurations can handle extreme conditions. Such as steam jacketing for liquid asphalt, oversized chambers for flashing applications, temperature designs for liquid nitrogen and refrigerants. Numerous metals and alloys ( titanium, Incoloy and Monel ) are available for varying combinations. Like high-temperature, high-pressure, low-specific-gravity and corrosive-fluid applications.  Magnetic level gauges can also be outfitted with magnetostrictive and guided-wave radar transmitters. This allow the gauge’s local indication to be converted into 4-20 mA outputs and digital communication. That can be sent to a controller or control system.

Float level gauge is mainly composed of magnetic float, sensor and transmitter. When the magnetic float ball changes with the liquid level and floats up and down along the catheter. The magnetic steel in the float ball attracts the reed switch at the corresponding position in the sensor. Which changes the total resistance (or voltage) of the sensor. The transmitter then converts the changed resistance (or voltage) signal into a 4-20mA current signal output.
The float ball level gauge uses a magnetic float ball as a measuring element. Which makes the resistance in the sensor change linearly through magnetic coupling. The smart converter converts the resistance change into a 4-20mA standard current signal. It can display the percentage of liquid level, the current of 4 ~ 20mA and the value of liquid level. Remote transmission control room can realize automatic detection, control and recording of liquid level. The instrument is suitable for the sewage treatment of petroleum, chemical, power, light industry and pharmaceutical industries. And the measurement of the medium level in various atmospheric and pressure vessels. It is especially ideal for the liquid level measurement of underground storage tanks and storage tanks.

Features of Float level transmitters:

  • Suitable for the measurement of the liquid level and interface of the liquid medium in the container. In addition to on-site instructions, it can be equipped with remote transmitters, alarm switches and complete detection functions.
  • Innovative indication, intuitive reading, eye-catching, observing the direction of the indicator can be according to user needsChange the angle.
  • Large measuring range, not limited by the height of the storage tank.
  • The indicating mechanism is completely isolated from the measured medium, with good sealing, high reliability and safe use.
  • Simple structure, easy installation, easy maintenance, corrosion resistance, no power supply required, explosion-proof. At the lower limit, the float floats upright on the water.

Extended reading: Diesel fuel tank level gauges & indicators

After understanding these 7 types of Tank Level Senors, if you are experienced, you can purchase Tank Level Senors on the product details page. If you are new to this, then perhaps you need to continue to consider the measurement medium and monitoring requirements.

The following content is based on our many years of experience in liquid level measurement services. We at Sino-Inst have long been providing users with various tank level measurement solutions.

First, we recommend that you consider the measuring medium. For example, the most common measurement is the liquid level of water and diesel.

Water Tank Level Sensor

The water level sensor of your water tank is an essential component. If not repaired or replaced, a sensor can become damaged over time and fail entirely. Too much water can cause a malfunction and too little water means inadequate water pressure. Either way, repairing or replacing holding tanks is an expensive task you shouldn’t have to undertake because of sub-par sensors.
With Sino-Inst’s water tank level sensors, there’s nothing to break down or rust and our models have a 99% success rate!

In the high unlikely event that you experience any issues with your product, call us and we’ll replace or repair it immediately at no charge.

Read more about our water tank level sensors and control systems.

Hydrostatic pressure for Water level measurement

SI-151 Hydrostatic Level Sensor
SMT3151TR Hydrostatic level transmitter-Rod Type
SI-PCM260 Deep Well Water Level Sensor

Extended reading: Hydrostatic Pressure Transmitter

Diesel storage tanks -Explosion Proof level sensors

For diesel, gasoline, or other oils that require explosion-proof storage tanks. Liquid level measurement requires level sensors to meet explosion-proof requirements.

For example, explosion-proof ultrasonic level meter, explosion-proof radar level meter, etc.

non-contact tank level sensors

Of course, there are many cases where we need to measure chemical liquids, such as hydrochloric acid, liquid ammonia, etc.

Chemical Tank Level Measurement

Sino-Inst Tank level sensors expand the range of environments in which our sensors operate. Some common chemicals can damage or corrode sensor materials, even 316 stainless steel. Transducer elements and bonding adhesives are also susceptible. Our tank level sensors avoid these problems by using a continuous injection molded housing of Polyvinylidene fluoride (PVDF), a highly non-reactive thermoplastic that resists solvents, acids and hydrocarbons.

Tank level sensors have both top and bottom mounting threads and include a potted-in, PUR-jacketed, UV resistant cable. Verify your chemicals and operating temperatures with this compatibility chart. All ToughSonic sensors include analog, switch and data interfaces and compatible setup software, included at no charge.

Extended reading: Corrosive Liquid Chemical Level Sensor in Chemical Processing

OK. Once you know your measuring medium. Then you need to identify your monitoring needs. For example, you need to transmit the liquid level signal to the PLC system through 4-20mA.

All tank level sensors mentioned in this article can output 4-20mA.

The 4-20 mA current loop is the prevailing process control signal in many industries.It is an ideal method of transferring process information. Because the current does not change as it travels from the transmitter to receiver. It is also much simpler and cost-effective.However, voltage drops and the number of process variables,that need to be monitored can impact its cost and complexity.By knowing these fundamentals you will be able to make more informed decisions about process control in your facility. Which could affect your bottom line.

Extended reading: Industrial Tank level indicators and Tank Level Gauges

An analog signal refers to information represented by a continuously changing physical quantity. The amplitude, frequency, or phase of the signal changes continuously over time, or the characteristic amount of the representative information can be presented at any instant as a continuous time interval. Any value signal.

Sino-Inst’s tank level gauge provides multiple output modes, including analog voltage and current, digital, RS485, etc. The output signal can provide a position, multiple positions, or a position plus a temperature output. The detailed multi-function output mode provides customers with more choices.

Extended Reading: How to Measure Volume of Liquid

Continuous level sensors provide level monitoring of an entire system. They measure liquid level in a range, rather than at a single point, outputting an analog signal that correlates to the liquid level inside your tank or vessel.

Extended reading: What is a capacitive liquid level sensor?

If you do not have a monitoring system similar to a PLC, but you need to monitor the tank level in the office, you can configure our level-volume recorder.

Extended reading: GWR Solid Level Sensor-Cement silo-Ash powder measure

Featured Continuous level sensors

SI-U01 Float Level Sensor
SI-U02 Multi-Point Liquid Level Float Switch
SI-U03 Float Switch Water Level Controller
SI-U04 Magnetic Float Level Sensor-Reed Switch

Tank Level Sensor Industries & Applications

Continuous level transmitters are versatile in monitoring liquid level needs. They can monitor water, diesel, lube oils and fuels, as well as various chemical and petrochemical liquids.

Storage tanks are widely used in the fluid industry to store raw materials, finished products, and intermediate products. They have an irreplaceable role in ensuring the safe production of equipment, energy-saving and emission reduction and improving the overall management level. National strategic reserves are also inseparable from various types of Storage tanks. 

Industrial storage tanks are generally steel storage tanks. Carbon steel, low-temperature steel, stainless steel, and other materials are selected according to the characteristics of the storage medium, storage temperature, pressure, and other parameters. Other materials such as FRP and plastic are not considered due to fire and pressure resistance.

Common liquid level sensor application tank level monitoring:

  • Chemical injection
  • Hydraulic and lube oil tanks
  • Drilling fluid (mud) tank monitoring
  • Liquid level monitoring during transfer
  • Food and Beverage
  • HVAC
  • Medical
  • Printing (Ink Handling Systems)
  • Off-Highway Vehicles
  • Semiconductor

Extended reading: Types of Fuel-Diesel Level Sensors

How Tank Level Sensors Work?

The level of the liquid medium in the container is called the liquid level. And the instrument that measures the liquid level is called the liquid level transmitter. Level transmitter is a kind of level instrument.

There are two types of level transmitters, one is continuous and the other is point-off. The continuous level transmitter is a real-time monitor of the height of the liquid in the container. The point type, which generally takes two points, high and low, and outputs an alarm signal when the medium in the container reaches these two points. The types of liquid level transmitters are very wide. Specific include magnetic flap liquid level gauge, tuning fork vibration type, differential pressure type, pressure type. Ultrasonic, magnetostrictive liquid level gauge, magnetic flap, radar, and so on.

Levels of media such as: water, viscous fluids, and fuels, or dry media such as bulk solids and powders can be measured using the transmitter.

Level measurement transmitters are used in a myriad of applications that require level measurement within containers or tanks. These transmitters often find their application in material handling, food and beverage, power, chemical, and water treatment industries.

About Level Sensor Types and how they work, OMEGA Engineering has a good explanation. Video source

Technical Support


Q&A

Fluid level sensors are termed as the sensors used for detecting liquid levels or interfaces between liquids. Such as water and oil or solids and liquids. These sensors can also be defined as transducers or as integrated systems with instrumentation and control capabilities. This type of fluid level sensor is one of the most important sensors. Fluid level sensor plays a vital role in a variety of industrial and applications.

Industrial applications include fluid-level sensing in transport tanks, storage tanks and water treatment tanks. And also in the petrochemical industries for sensing liquids. Such as petrol, diesel and other fuels. Liquid level measurement is significant in household applications. Including electronic devices. Such as, water dispensers, water evaporators, steamers.

The monitoring system of boilers, heating systems. Washing machines, steam irons, juice squeezers, automated coffee machines, etc.

Fluid Level sensors are designed for specific applications compared to general applications.

Extended reading: Diesel Tank Level Monitoring System

Point level sensors are devices that detect variation in liquid levels. And the levels are based on the presence or absence of liquid media at various points in a vessel or tank. Most often, the function of point level sensors is: High level or low-level alarms. Spill-prevention sensors. Pump protection alarms. Or pump control components.

In the simplest terms, point level sensors operate in either an on or off state. And point level sensors are used to control external devices that share an on/off functionality.
Examples of liquid level sensors that can work as point-level sensors:

Fuel tank level measurement can be achieved by using fuel level sensors. These Fuel level sensors work on a hydrostatic pressure principle. By installing a sensor at the base of the fuel tank can associate the pressure created by the level of fuel above the device. And this has a direct relationship to the level by a simple calculation. This calculation can be seen by using the Impress conversion software here.

The things to consider when selecting a fuel level sensor is that the materials used are compatible with the type of fuel you have so for instance on the submersible devices you must make sure that the pressure diaphragm, O ring seals, housing material and Cable sheath are all suitable for complete submersion in the fuel.

Typically we would suggest using a PTFE or FEP cable sheath but for petrol or gasoline although a specially made Hytrel cable may be necessary.

If the installation is a screw-type fitting in the base of the tank then just the housing, O ring seal, and diaphragm are of concern. Ceramic pressure sensor or stainless steel silicon pressure sensors are fine and a stainless steel housing are recommended.

Ultrasonic Sensors are good choice for Water Level Measurement.

The water and wastewater industry has many requirements for measuring the level of water. In applications such as flumes, weirs, pipes, tanks, wells, basins, and cooling towers. Ultrasonic sensors are reliable, cost-effective instruments for these applications. In operation, the sensor is mounted over the water. To determine the distance to the water, it transmits a sound pulse that reflects from the surface of the water. And measures the time it takes for the echo to return.

Sometimes structural components, such as a small pipe, are located in the acoustic path between the ultrasonic sensor and the water. They can reflect a portion of the sound and produce a false echo that interferes with the ability of the sensor to properly detect the echo from the surface of the water. Advanced ultrasonic sensors can be adjusted to ignore these false echoes, which therefore enables them to provide accurate water level measurements.

Extended reading: Sludge flow meter for sewage treatment return activated sludge system

There are 7 main types of level transmitters that Sino-Instrument offers. Each type of transmitter works in a different way, and makes it useful for different types of processes.

  • Capacitance Level Transmitters
  • Hydrostatic Level Transmitters
  • Magnetic Level Transmitters
  • Radar Fill Level Transmitters
  • Ultrasonic Level Transmitter
  • Guided Microwave Level Transmitters
  • Liquid Level Transmitters

Let’s take a closer look at how different types of level transmitters work.

Read more: What is level transmitter working principle?

Sino-Inst offers over 10 level transmitters for level measurement.

About 50% of these are liquid level meters, 40% is the tank level sensor.

A wide variety of level meters options are available to you, such as free samples, paid samples.

Sino-Instrument is a globally recognized supplier and manufacturer of level measurement instrumentation, located in China.

Request a Quote

Please enable JavaScript in your browser to submit the form

Request a Quote

Please enable JavaScript in your browser to submit the form

Guide to Ultrasonic Level Transmitters-for Continuous Non Contact Level Measurement of Liquid & Solids.

What is an Ultrasonic level transmitter?

Ultrasonic Level Transmitters & Ultrasonic Level Sensors are designed to provide accurate and reliable level sensing for difficult to monitor fluids, where contact with media is not desirable from the extremes of sending: ultrapure to corrosive or even dirty where coating or scaling is possible. Ultrasonic level transmitters have no moving parts, are easy to install and simple to use.

Ultrasonic level measurement provides continuous, non-contact and maintenance-free level measurement of fluids, pastes, sludges and powdery to coarse bulk materials. The measurement is unaffected by dielectric constant, density or humidity and also unaffected by build-up due to the self-cleaning effect of the sensors.

The basics of ultrasonic level transmitters – how they work and what they’re used for

Ultrasonic Level Transmitters working principle

The Ultrasonic Level Transmitter consists of three parts: ultrasonic transducer (probe), drive circuit (module), and electronic display module.

The Ultrasonic Sensor is installed on the storage tank or process vessel. The sensor sends out a sound wave, which ricochets off the surface of the liquid and returns to the sensor. The time it takes for the sound wave to travel from the sensor to the liquid surface and return to the sensor is measured. This time delay is proportional to the level of the liquid.

The drive circuit processes the signal from the Ultrasonic Sensor, compensates for adverse conditions (temperature, pressure, etc) and converts it into a standard 4-20mA or 0-5/10 Vdc signal that can be read by a PLC, DCS or Display/Transmitter.

The Display/Transmitter converts the 4-20mA or 0-5/10 Vdc signal into a display reading in the unit of measure required (feet, inches, meters, centimeters, etc). Ultrasonic level transmitters can be outfitted with local displays and push button controls for easy configuration without the need of a laptop or other computer.

Applications

Ultrasonic level transmitters are used for inventory management and process automation in a wide range of industries. Applications include:

  • Food & Beverage
  • Water & Waste Water
  • Chemical
  • Petroleum
  • Pharmaceutical

Read more about: Ultrasonic Level Sensor Applications

Featured Ultrasonic level transmitters

ModelIntegrated ModelSplit model
Pictures
Measuring range5m、10m、15m、20m、30m5m、10m、15m、20m、30m
Accuracy0.5%~1.0%0.5%~1.0%
Resolution3mm or 0.1% (choose the bigger)3mm or 0.1% (choose the bigger)
DisplayLCD LCD
Analog output4 wire system 4~20mA/510Q loading
2 wire system 4~20mA/250Q loading
4~20mA/510Q loading
Relay output2 sets of AC 250V/ 8A or DC 30V/ 5A are optional, state is programmable2 sets of single-channel are (optional), the double channel is 4 sets of AC 250V/ 8A or DC 30V/ 5A, the state is programmable
Power supplyStandard: 24VDC 
Optional: 220VAC + 15% 50Hz
Standard: 220V AC + 15% 50Hz
Optional: 24VDC 120m
Customized 12VDC or battery-powered
Environmental temperatureMeter display -20 ~ +60°C 
Probe -20~+80°C
Meter display -20~ +60°C 
Probe-20~+80°C
CommunicationOptional 485,232 communication (manufacturer agreement)Optional 485, 232 communication (manufacturer agreement)
Protection classDisplay meter IP65, Probe Ip68Display meter IP65, Probe Ip68
Probe cableNo100m reachable, standard 10m
Probe installationSelection based on measuring range and probeSelection based on measuring range and probe

Ultrasonic level transmitter data sheet

Extended reading: liquid nitrogen level sensor

The benefits of using an ultrasonic level transmitter

– Ultrasonic level transmitters are easy to install and simple to use.

Ultrasonic level measurement provides continuous, non-contact and maintenance-free level measurement of fluids, pastes, sludges and powdery to coarse bulk materials.

– Ultrasonic level transmitters are unaffected by dielectric constant, density or humidity and also unaffected by build-up due to the self-cleaning effect of the sensors.

Sino-Inst offers a wide range of Ultrasonic Level Transmitters that can be used in various industries for inventory management and process automation. If you have any questions about which Ultrasonic Level Transmitter is right for your application, please contact us and we will be happy to assist you.

Read more about 7 Level Senors for Tank Level Measurement

How to choose the right ultrasonic level transmitter for your needs

1. The ultrasonic level meter can only be used for the medium that can fully reflect sound waves and propagate sound waves. For the sound wave adsorption ability of the medium, it is not suitable to use ultrasonic level meter.

2. The ultrasonic level meter can not be applied to vacuum occasions, and not for negative pressure occasions. Because the propagation of ultrasonic waves need air medium. And the thin air environment is very unfavorable to ultrasonic propagation. Plus the sound attenuation will therefore increase. Ultimately, it will lead to serious errors in measurement or even can not be measured.

3. If the measured medium is a volatile liquid, or contains a large amount of water vapor, dust, bubbles, suspended particles and other media, the ultrasonic level meter should not be used.
This is due to the fact that when the sound waves from the probe of the ultrasonic level meter encounter the above medium, irregular reflection and scattering will occur. The probe will not be able to receive the normal signal. And these media will absorb the sound waves. This causes the attenuation of sound waves and affects the measurement results.

4. If there are obstacles or equipment that affect the propagation of sound waves inside the vessel. Then the ultrasonic level meter is not recommended.

5. Ultrasonic level meter can generally only be applied in the normal temperature and pressure range. If the pressure is too high, it will have a strong inhibiting effect on the sound speed of the acoustic wave. Eventually, it will affect the measurement accuracy, or even impossible to measure. And the temperature generally cannot exceed 100℃.

Tips for ultrasonic level transmitter installation

Before installing the ultrasonic level Transmitters, please read the instruction manual of the ultrasonic level Transmitters carefully. Work according to the instructions.

At the same time, it should be reconfirmed whether the model of the instrument matches the environmental requirements of the site such as process pressure, process temperature, and chemical properties of the medium. To ensure that the instrument can be used normally after installation.

To install the ultrasonic level meter, please observe the following operating rules:

  1. Try to avoid in-tank facilities such as ladders, heating equipment, limit switch brackets, etc. for installation.
  2. The ultrasonic beam must not intersect the feed stream. At the same time, pay attention to ensure that the highest material level does not enter the measurement blind area during installation. The ultrasonic level Transmitters must not be installed above the feed stream.
  3. When installing the ultrasonic level Transmitters, it should keep a certain distance from the tank wall. And keep the transducer perpendicular to the liquid surface as much as possible.
  4. When installed outdoors, the ultrasonic level Transmitters should take sunshade and rainproof measures. To avoid direct sunlight and reduce measurement errors caused by temperature changes. At the same time should also pay attention to moisture.
  5. The ultrasonic level Transmitters installed in the hazardous area must comply with the installation regulations of the national explosion-proof hazardous area. The intrinsically safe ultrasonic liquid level Transmitter is installed in the occasion with explosion-proof requirements, and the ultrasonic liquid level Transmitter must be grounded.
  6. When there is stirring in the container. The ultrasonic level Transmitters should be kept away from the agitator. In order to eliminate the false echo effect produced by the stirring blade. If foam or waves are created due to agitation, the still-pipe installation method should be used.
  7. When there is foam in the container. When feeding, stirring or doing other processing in the container, foam will be formed on the surface of some media, which will attenuate the signal of the ultrasonic level Transmitter. The sensor should be installed in a still-pipe or a guided-wave radar level Transmitters should be used. Guided wave radar level Transmitters measurements are not affected by foam and are ideal for this application.
  8. When there is airflow in the container. If there is a strong airflow or air vortex in the container, or if it is installed outdoors and in a very windy place. The sensor should be installed in a still-pipe or a guided-wave radar level Transmitters should be used.

Depending on the shape of the tank top of the container, the installation position of the ultrasonic level transmitter should be selected to avoid multiple reflection echoes between the liquid level and the top wall. In order to reduce interference, reduce noise signal and ensure the accuracy of detection.

Installation position of ultrasonic level transmitters

The reasonable installation position of the ultrasonic level transmitter should be determined according to the different top and internal structure shapes of the liquid container:

A. Grooved container:

  1. The support frame should be firm and reliable;
  2. The height of the intersection line of the beam emitted by the probe and the tank wall must be less than or equal to the minimum height of the liquid level to be measured;
  3. The installation height should be within the required range.

B. Arched container:

Meters cannot be installed on vaulted ceilings. It should be installed at 1/2 or 1/3 of the radius of the empowerment.

C. Conical container:

For conical containers with flat tops. The best place to install the meter is in the center of the top of the vessel. This ensures that you measure to the bottom of the container.

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Frequently
Asked
Questions

Ultrasonic level transmitters use sound waves to measure the level of a liquid in a tank. The transmitter sends out a sound wave and measures the time it takes for the sound wave to bounce back. The transmitter then calculates the distance from the sensor to the liquid surface and displays the level on a digital display.

An ultrasonic level sensor is a device that uses sound waves to measure the level of liquids, pastes, sludges, and other similar substances. Ultrasonic sensors are unaffected by dielectric constant, density or humidity, and also have a self-cleaning effect that prevents build-up.

Ultrasonic level measurement works by sending out a sound wave from the sensor and measuring the time it takes for the sound wave to bounce back. The time it takes for the sound wave to bounce back is directly proportional to the level of the liquid. Ultrasonic sensors are very accurate and can be used in a wide range of applications.

Radar level transmitters use microwave energy to measure the level of liquids, while ultrasonic level transmitters use sound waves. Both technologies have their own advantages and disadvantages. Radar is more accurate than ultrasonic, but it is also more expensive. Ultrasonic is less accurate than radar, but it is less expensive and easier to install.

Sino-Ins offers 20 ultrasonic level transmitters products.

About 13% of these are ultrasonic level transducers, 4% are ultrasonic level indicators.

A wide variety of ultrasonic level transmitters options is available to you, such as free samples, paid samples.

Sino-Inst is an ultrasonic level transmitter supplier, located in China.

Ultrasonic level transmitter products are most popular in North America, Mid East, and Eastern Europe.

The United States, and India, which export 99%, 1%, and 1% of ultrasonic level transmitters respectively.

You can ensure product safety by selecting from a certified supplier, with ISO9001, ISO14001 certification.

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