SI-FMF15 FMCW Radar for High Temperature Level Sensor

High temperature level sensor is based on FMCW Radar to measure high temperature liquid. Non-contact measurement. The temperature is as high as 240°C. IP67 protection. rs485 output.

SI-FMF15 FMCW Radar High Temperature Level Sensor

High Temperature Level Sensor is also called high temperature molten salt level sensor. Use continuous frequency modulation wave radar to measure. SI-FMF15 FMCW Radar High Temperature Level Sensor is manufactured based on the principle of linear frequency adjustment-radar working. It can ensure the accurate and stable liquid level measurement of the radar in high temperature, high pressure, strong corrosion, strong dust and other environments. High temperature type 240℃, special customization can reach 1200℃.

Sino-Inst offers a variety of FMCW Radar High Temperature Level Sensors for industrial level measurement. If you have any questions, please contact our sales engineers.

Features of SI-FMF15 FMCW Radar High Temperature Level Sensor

  1. Measurement accuracy
    The measurement accuracy of the terahertz frequency-modulated continuous wave radar level meter is ±1mm. Reliable and high-precision measurement. It really reduces the workload of field operators.
  2. Launch angle
    Radar wave emission angle <2°. Even in extremely complex installation environment, it can measure the material level stably and accurately.
  3. Measuring range
    The measurement range of the terahertz FM radar level meter is 0.08m-150m. It has a very small blind area and a large measurement range. It can meet most measurement occasions.
  4. Penetration
    The terahertz frequency-modulated continuous wave radar level gauge is extremely penetrating. According to the dielectric constant of the crystalline medium, it can penetrate the crystalline layer of up to 100mm.
  5. High temperature conditions
    The terahertz FM radar level meter has good penetration performance. For high temperature occasions, thermal insulation accessories such as ceramic or quartz glass can be added to the front end of the antenna. With the special environment learning function, it can measure high temperature liquids.
  6. Strong corrosiveness
    It has good penetration performance. For strong corrosion occasions, the front end of the antenna can be equipped with PTFE or PFA anti-corrosion sheath. And the maximum thickness of 30mm fluoroplastic can be added. It has good pressure resistance while anti-corrosion.
  7. Foam products
    It has good penetration performance. Therefore, it can penetrate the foam up to 1000mm for liquid level measurement. The terahertz frequency modulation radar level gauge can also measure the foam itself.
  8. Sensitivity
    It has three adjustable sensitivity. When high sensitivity is selected, the radar response time is less than 1S.

Specifications of SI-FMF15 FMCW Radar High Temperature Level Sensor

Measuring medium:Liquid
Measuring range:0.1m~120m
Process connection:Flange≥DN80
Process temperature:Standard model -60~130℃;
high temperature model -60~240℃;
special customization -60~1200℃
Process pressure:-0.1~2.5 MPa
Accuracy:±2mm         
Protection level:IP67
Frequency Range:123GHz
power supply:Two-wire system (DC24V)/four-wire system (DC12V~24V)/four-wire system (AC220V)
Explosion-proof grade:Exia ⅡC T6 Ga / Exd IIC T6 Gb
Housing:Aluminum/plastic/stainless steel
Signal output:Two-wire system 4…20mA/HART protocol Four-wire system 4…20mA/RS485 Mod bus

Extended reading: What is Modbus Protocol?

SI-FMF15 FMCW Radar Level Sensor Applicable Medium

  • Level measurement of solids (powders, granules, blocks);
  • Level measurement of plastic particles with low dielectric constant;
  • Liquid level measurement. Reactor liquid level. Large steam level. Foam product level. Crystalline product level. Ultra-high temperature product level. Ultra high pressure product level. Hygienic product level.

Extended reading: Dam water level measurement

Advantages of FM Radar Level Meter

FMCW radar level meter is suitable for various complex working conditions. It can also ensure measurement stability and accuracy in high temperature and high dust environments.

  • Not affected by atmospheric precipitation;
  • Ambient temperature from -60℃;
  • from outside the storage tank;
  • The inner antenna of the terahertz FM continuous wave radar level meter is heated and protected by a fluoroplastic lens
  • The measurement beam is narrow. Easy installation and stable measurement;
  • Level measurement accuracy;
  • Not limited by the temperature in the container;
  • Evaporation and dust do not affect the measurement;
  • Boiling liquid level measurement;
  • Corrosive liquid level measurement. No contact, no corrosion;

FMCW Radar Working Principle

In the early years, a non-contact frequency-modulated continuous wave radar level meter produced by a company in the United States used FMCW technology to perform more accurate level measurement for more complex occasions. This FMCW technology has caused a global sensation. It has made more researchers devote themselves to FMCW technology. FMCW here is frequency modulated continuous wave.

This FMCW radar technology uses a high frequency sweep signal typically 8.5 to 9.9 GHz. The radar signal is sent from one end of the antenna and is received by the receiver after time t. The frequency difference Δf between the transmitting and receiving is converted into the level of the measured medium by the Fourier transform method.

However, with the development of the times and the efforts of scientific researchers, the continuous waves of 26GHz, 28GHz, 80GHz and 120GHz have been derived from the FM continuous wave radar level gauge.

FM continuous wave radar level meter is a general-purpose instrument for measuring coal, cement, grain, alumina, limestone, chemical raw materials and other materials. It is widely used in cement, chemical, environmental protection, electric power, food and other industries.

The 120GHz radar level meter is especially suitable for high temperature, high pressure or high dust, and multi-stirring environments. It meets many measurement requirements that require a large range and high precision.

Terahertz FM CW radar level meter mainly uses triangular FM continuous wave. After the transmitted signal is scattered by the target, it is accepted by the antenna. The delay time τ=2R/c. Among them, R is the distance from the target to the antenna, and c is the propagation speed of the electromagnetic wave. .

When the detection target is stationary, the distance calculation formula is R=(cT/4B)×fb, where T is the period of the triangular wave, and B is the frequency modulation bandwidth.

From the formula R=(cT/4B)×fb, it can be obtained that the frequency fb of the beat frequency signal has a linear relationship with the distance R. Therefore, the key to the ranging system is to measure the frequency of the beat frequency signal.

Under certain conditions of bandwidth B and period T, the distance R can be calculated as long as the frequency fb is obtained. Therefore, the accuracy of frequency measurement directly affects the accuracy of distance measurement.

The difference frequency signal is usually sampled by A/D and then calculated by FFT to obtain the discrete spectrum of N points. Then fb is obtained by the peak frequency of the spectrum. Because the discrete spectrum will have a frequency domain sampling interval △f=fs/N.

In the formula, fs is the sampling frequency, and N is the number of sampling points.

The discrete spectrum sampling obtained by FFT generally cannot collect the peak point of signal frequency. That is, the integer multiple of the frequency interval does not coincide with the peak point, which causes the result of FFT analysis to be inconsistent with the actual frequency, resulting in frequency estimation error.

Extended Reading: Case: High Temperature Radar Level Transmitter for Melted Salt-Solar Photovoltaic Power Station

Level Measurement with FMCW Radar in Steam and High Temperature

When the measured medium is heated, or stored products with relevant physical and chemical properties (acids, alkalis, alcohols, etc.), there may be vapor accumulation in the upper space of the measured medium.

There are various vapors in the air in the space between the level gauge and the medium. It will not affect the accuracy and stability of the measurement. The FM continuous wave radar level gauge has this characteristic.

Level measurement by means of ultrasonic or optical (laser) means is a very unstable and inaccurate method. Because the speed of sound propagation depends on the composition of the atmosphere through which it passes. Direct optical visibility is required for measurement by laser means.

Level Sensors for High Temperature Applications

The high temperature and high pressure guided wave radar level sensor is specially designed for high temperature and high pressure occasions. The product is mainly used for liquid level measurement on various boiler drums. Has high safety and accuracy. The highest rated pressure reaches 40MPa. The highest rated temperature reaches 400℃. It is suitable for high and low pressure heaters, condensers and deaerators in thermal power plants. As well as for liquid level measurement under high temperature, high pressure, vacuum and other steam conditions.

Hydrostatic level transmitter is also called hydrostatic level gauge. The rod-type Hydrostatic level transmitter utilizes the linear relationship between liquid height, density, and pressure. The change of the level is converted into a linear 4-20mADC standard signal output. Suitable for tank level measurement. Flange or threaded installation. Can withstand high temperatures up to 450 ℃.

High Temperature Float Switch

Float level sensor can be widely used for continuous measurement of the liquid level (boundary level): High temperature. High pressure. Viscous, dirty media. Asphalt, wax-containing oil products and flammable, explosive, corrosive media.

Float level sensor (float switch) is one type continuous level sensor for industrial level measurement. Float level sensor has a magnetic float that rises and falls as liquid level changes. The movement of the float creates a magnetic field. Through the magnetic coupling effect, the internal resistance of the sensor changes linearly. The resistance change is converted into a standard current signal of 4 ~ 20mA by an intelligent converter. The percentage of the liquid level, 4 ~ 20mA current and liquid level value, can be displayed on site. Applications like: water tank, fuel tank, level measurement and level control. Vertical, horizontal, and side mounted, all can be satisfied.

Intelligent Solutions for High Temperature and Pressure

Related Blogs

Sino-Inst offers over 10 FMCW Radar High Temperature Level Sensors for level measurement. About 50% of these are Radar level meters, 40% is the tank level sensor.

A wide variety of FMCW Radar High Temperature Level Sensors options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of FMCW Radar High Temperature Level measurement instrumentation, located in China.

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Miniature Thermocouples–Smaller Than Armored Thermocouples

Miniature thermocouples are smaller than armored thermocouples. It has more advantages, such as: bending, high pressure resistance, fast thermal response time, sturdiness and durability, etc.

Miniature thermocouples are the same as armored thermocouples and assembled thermocouples. As a sensor for measuring temperature. They are usually used in conjunction with display instruments, recorders and electronic regulators. At the same time, miniature thermocouples can also be used as assembly thermocouples. Temperature sensing element. Temperature probes for applications with tight space requirements, limited access or other considerations. Typical miniature thermocouple applications include analytical instrumentation and medical devices.It is an indispensable temperature-measuring device in textile, tape and other industries.

It can directly measure the temperature of liquid, steam and gas medium and solid surface in the range of 0℃~600℃ in various production processes. are especially suitable for temperature measurement and control in narrow and bending places. Widely used in chemical, chemical fiber and pharmaceutical industries

Sino-Inst offers a variety of miniature thermocouple . If you have any questions, please contact our sales engineers.

Technical Parameters

  • Accuracy level: I or II [plus or minus 1.5 degrees below 375° is the first level standard. Plus or minus 2.5 degrees is the secondary standard]
  • Nominal diameter: Φ1 Φ0.5 Φ0.35 [generally the smallest outer diameter]

The Main Technical Parameters Of Miniature Thermocouples

  • Models and Specifications Accuracy grade: I or II
  • Nominal diameter: Φ1
  • Bending radius: R≥5D
  • Nominal pressure: normal pressure

About Temperature

The Celsius Temperature Scale (°C) Stipulates:

Under standard atmospheric pressure, the melting point of ice is 0°C, the boiling point of water is 100°C, and the middle is divided into 100 equal parts, each divided into 1°C, the symbol is °C.

The Fahrenheit Temperature Scale (℉) Stipulates:

Under standard atmospheric pressure, the melting point of ice is 32 degrees, the boiling point of water is 212 degrees, and the middle is divided into 180 equal parts, and each equal part is 1 degree Fahrenheit. The symbol is ℉.

The Thermodynamic Temperature Scale (symbol T)

The thermodynamic temperature scale (symbol T) is also called the Kelvin temperature scale (symbol K), or absolute temperature scale, which stipulates that the temperature when the molecular motion stops is absolute zero.

Principle Of Operation

In 1821, the German physicist Thomas Johann Seebeck discovered that when different metals are joined at the ends and there is a temperature difference between the joints, a magnetic field is observed. At the time, Seebeck referred to this consequence as thermo-magnetism. The magnetic field he observed was later shown to be due to thermo-electric current. In practical use, the voltage generated at a single junction of two different types of wire is what is of interest as this can be used to measure temperature at very high and low temperatures. The magnitude of the voltage depends on the types of wire being used. Generally, the voltage is in the microvolt range and care must be taken to obtain a usable measurement. Although very little current flows, power can be generated by a single thermocouple junction. Power generation using multiple thermocouples, as in a thermopile, is common.

Thermocouple from Wikipedia.

Model And Specifications Of Miniature Thermocouples

ModelGraduationRange of temperature measurement  ℃Thermal response timeMaterial for protective tube
WRE-203SE-40~250<5S1Cr18Ni9Ti
WRE-204SE-40~250<8S1Cr18Ni9Ti
WRE-205SE-40~250<10S1Cr18Ni9Ti
WZP-203SPt100A -30-300       B -50-500<5S1Cr18Ni9Ti
WZP-205SPt101A -30-300       B -50-500<8S1Cr18Ni9Ti
WZP-206SPt102A -30-300       B -50-500<10S1Cr18Ni9Ti

Extended reading:  Tri Clamp Sanitary Thermometers

Miniature Thermocouple Connectors

Standard and miniature connectors are used with thermocouples, extension wires and compensation cables. No false thermal EMFs are created in the connection. Uncompensated miniature copper connectors are also available.

All contacts are polarized. to ensure proper connection. And these connectors are fully compatible with RS thermocouples and thermocouple wiring products of the same type.

Uses: Suitable for thermocouple and RTD connectors.
Suitable for fine wire and mineral insulated cables.

Material
a) Thermoplastic (200℃)
b) Thermosetting (350℃)
C) Ceramic (650℃)

About Sheathed thermocouple: Sheathed thermocouple can directly measure the temperature of liquid, steam and gaseous media and solid surfaces in the range of 0℃~1200℃ in various production processes. Sheathed thermocouples are usually used along with display instruments, recording instruments, electronic computers and so on. It is able to directly measure the temperature of liquid, steam and gas and solid surface in a variety of production processes within the range of 0 ~1300℃.

Extended reading: RTD vs. Thermocouple: What’s the Difference, and Which Should You Use?

Related Blog

Sino-Inst, Manufacuturer for Thermocouples, like: Armoured thermocouple, assembly thermocouple, explosion-proof thermocouple, etc.

Sino-Inst’s Thermocouples, made in China, Having good Quality, With better price. Our Temperature measurement instruments are widely used in China, India, Pakistan, US, and other countries.

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SI-FMF13 FMCW Radar Water Level Sensor

Radar Water Level Sensor for Non-contact water level measurement. Two-wire system 4…20mA/HART protocol; four-wire system 4…20mA/RS485 Mod bus. Explosion-proof Exia ⅡC T6 Ga / Exd IIC T6 Gb.

Radar Water Level Sensor for Non-contact water level measurement. SI-FMF13 FMCW Radar Water Level Sensor is the ideal solution for measuring the water level in tank, dams, ponds, rivers, etc. The measuring range is up to 100 meters. IP67waterproof. Frequency modulated continuous wave radar level sensors antenna has been further optimized. The new and fast microprocessor can perform higher rate signal processing.

Sino-Inst offers a variety of FMCW Radar Water Level Sensors for industrial level measurement. If you have any questions, please contact our sales engineers.

Features of SI-FMF13 FMCW Radar Water Level Sensor

  • 120GHz (ISM standard band) distance detector based on the working principle of radar.
  • FMCW planar microstrip radar non-contact detection. Stable working all-weather.
  • The measurement error is less than ±1cm.
  • Radar antenna style: 11º×11º. Good directivity, low transmission loss.
  • Standard data communication interface (RS-232/RS-485) can be set.
  • Low power consumption, waterproof and lightning protection design. Suitable for various outdoor environments.
  • Small appearance. Easy to install and easy to maintain.

Specifications of SI-FMF13 FMCW Radar Water Level Sensor

Measuring medium:Liquid
Measuring range:0.1m~100m
Process connection:Flange≥DN80
Process temperature:-40~110℃
Process pressure:-0.1~0.3 MPa
Accuracy:±5mm (range between 35m-100m)
±2mm (range under 35m)
Protection level:IP67
Frequency Range:123GHz
power supply:Two-wire system (DC24V)/
four-wire system (DC12V~24V)/four-wire system (AC220V)
Explosion-proof grade:Exia ⅡC T6 Ga / Exd IIC T6 Gb
Housing:Aluminum/plastic/stainless steel
Signal output:Two-wire system 4…20mA/HART protocol Four-wire system 4…20mA/RS485 Mod bus

Lake Water Level Sensor

Radar water level sensor monitors the water level of rivers, lakes, tidal water reservoirs and reservoirs.

Solution requirements:

The radar water level sensor monitors the water level of rivers, lakes, tidal water reservoirs and reservoirs. It is suitable for installation and use in areas that are not convenient for wiring due to corrosion, pollution, and flood-related water level collection.

Transmit a short microwave pulse, and then measure the elapsed time between pulse transmission and return. The running time of a few meters is measured in units of nanometers. Therefore, a special time conversion program is required to accurately measure these short time periods.

The elapsed time measurement is used to calculate the distance between the sensor and the target (for example, water, grain, slurry). The distance value can then be used to determine the depth of the medium.

Extended reading: Radar Non Contact Water Level Sensor

Technical Support:

Pulse radar level transmitters provide water level measurement based on directly measuring the running time of microwave pulses transmitted to and reflected from the surface of the river being measured. Using rs485 two-wire signal transmission, power supply and low power consumption are safe for outdoor use.

RS485 interface can be connected with 485 line, insert 4g sim card in dtu. 232 to usb to connect to the computer. Open the configuration tool and set the server address and port in the dtu configuration tool.

The server port monitors to receive the data, and it can be analyzed according to the sensor protocol. If the platform is developed to the modbus standard, the sensor also supports modbus. The whole analysis process will be simpler.

Realize remote monitoring and management of liquid level and water level outdoors. Both dtu and sensor industrial-grade outdoor design can be powered by solar energy. Therefore, radar water level gauges can be used in some of the most challenging water level applications.

Advantages:

  • dtu rs485 bus access. Multi-device access, support rs232 interface;
  • Strong compatibility. Can be connected to five-parameter water quality equipment. Multiple sensors use one gateway;
  • Installed on the shore of the water area, on the measuring frame or “extension arm”. Adjust the mounting bracket according to the terrain;
  • The installation is simple and the price is low. No need for expensive installation procedures;
  • Low power consumption power supply enables the equipment to operate independently in the most remote areas;
  • Non-contact measurement principle. Not damaged by silt accumulation or debris;
  • Wireless transmission, avoid the trouble of pulling cables. Install and use, remotely unattended;
  • High-level industrial requirements for the appearance of the iron shell. Application in hazardous areas and harsh environments;

Extended reading: Capacitive water level sensor

More Water Level Sensors

Sino-Inst offers a variety of water level sensors for a wide range of conditions. Our sensors are ideally suited for monitoring water levels in streams, dams, and reservoirs. Our water level sensor products include:

Sino-Inst offers over 10 FMCW Radar Water Level Sensor for level measurement. About 50% of these are float liquid level meters, 40% is the Solid level sensors.

A wide variety of FMCW Radar Water Level Sensor options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of FMCW Radar Water Level Sensor instrumentation, located in China.

Request a Quote

SI-FMF12 Frequency Modulated Continuous Wave Radar Level Sensor

Frequency modulated continuous wave radar also known as FMCW radar. Frequency modulated continuous wave radar level sensors antenna has been further optimized. The new and fast microprocessor can perform higher rate signal processing.

Frequency modulated continuous wave radar refers to continuous wave radar whose transmitting frequency is modulated by a specific signal. Radar is divided into two categories: pulse radar and continuous wave radar according to the type of transmitted signal. The signal emitted by Frequency Modulated Continuous Wave Radar can be single-frequency continuous wave (CW) or frequency-modulated continuous wave (FMCW). FMCW radar can be used for both range measurement and Speed ​​measurement, and the advantages in short-distance measurement are increasingly obvious.

Sino-Inst offers a variety of Frequency modulated continuous wave radar for industrial level measurement. If you have any questions, please contact our sales engineers.

Features of FMCW Radar Level Sensor

  • 120GHz-130GHz FM wave radar. Terahertz radar used in industrial measurement field
  • 10GHz ultra-large FM scanning frequency width. Wide application range
  • 320*240dot TFT color LCD display. Easy to operate and friendly interface
  • Support standard HART, MODBUS, PROFIBUS bus protocol
  • Support multiple operation and configuration methods such as PC setting software, mobile phone APP, LCD keyboard module, tank side meter, etc.
  • 24VDC, 220VAC two power supply models
  • Simple installation structure. Adapt to various installation forms on site

Specifications of SI-FMF12 FMCW Radar Level Sensor

Measuring medium:Liquid
Measuring range:0.05m~35m
Process connection:G2A thread/flange≥DN65
Process temperature:-40~110℃
Process pressure:-0.1~1.6 MPa
Accuracy:±2mm
Protection level:IP67
Frequency Range:IP67
power supply:Two-wire system (DC24V)/four-wire system (DC12V~24V)/four-wire system (AC220V)
Explosion-proof grade:Exia ⅡC T6 Ga / Exd IIC T6 Gb
Housing:Aluminum/plastic/stainless steel
Signal output:Two-wire system 4…20mA/HART protocol Four-wire system 4…20mA/RS485 Mod bus

Extended Reading: Influence of Dielectric Constant on Liquid Level Measurement | Radar-Guided Wave Radar Level Meter

Frequency modulated continuous wave radar pros

120GHz-130GHz FM wave FMCW radar product (also called THz terahertz radar).
It uses a higher frequency THz band than Ku-band radar.

It has important applications in remote target detection, strong smoke and dust environment, long-distance imaging, multi-spectral imaging, etc. And can detect smaller targets than microwave radar and achieve more precise positioning. With higher resolution and stronger confidentiality.

What are terahertz (THz) electromagnetic waves?

It refers to electromagnetic waves and electromagnetic radiation with electromagnetic wave frequency between 100GHz ~ 10,000GHz (10THz).

This band is the area that humans have the least understanding and application development so far. Terahertz lies between mid-infrared and microwave on the electromagnetic spectrum, and represents the transition stage from quantum mechanism transmission theoretical physics to classical mechanism transmission theoretical physics.

1THz(=1000GHz) The wavelength of electromagnetic wave is 300um (0.3mm is about the diameter of human hair)

Difference between CW radar and FMCW radar

Radars are divided into pulse radars and continuous wave radars according to the types of transmitted signals. Conventional pulse radar emits periodic high-frequency pulses. Continuous wave radar emits continuous wave signals.

The signal emitted by continuous wave radar can be single frequency continuous wave (CW) or frequency modulated continuous wave (FMCW). There are also many ways of frequency modulation. The common ones are triangle wave, sawtooth wave, code modulation or noise frequency modulation.

Among them, the single-frequency continuous wave radar (CW) can only be used for speed measurement, not distance measurement. The FMCW radar can measure both range and speed, and its advantages in short-range measurement are becoming increasingly obvious.

From Wikipedia, we can learn more about Continuous-wave radar.

Frequency Modulated Continuous Wave Radar Working Principle

FM wave radar level sensor and distance formula:

Among them: C speed of light; fd Doppler frequency shift; fu triangle rising edge difference frequency; f0 FM initial frequency; T signal period; B signal bandwidth

The distance resolution depends on the frequency resolution of the DFT operation (Frequency Resolution). The frequency resolution of the DFT Fres is equal to:

T is the corresponding sampling time of the non-zero sampling value used for the DFT operation. If you use FFT + zero padding method to calculate the spectrum. T is the time corresponding to the sampled value of the non-zero-filled point.

The distance corresponding to the frequency resolution Fres is the range resolution Sres of the radar. Then, how to calculate the range resolution of the FMCW radar?

B: Frequency modulation width, unit Hz

T: Actual frequency modulation, in seconds

C: Speed of light, 3*10^8 meters/second

S: the distance between the radar and the object, meters

V: Frequency modulation speed, Hz/sec

t: wave propagation time, sec

V=BW/T  ②

t= 2S/C   ③

Assume that T is sampling during the entire frequency modulation period. And all sampling points are used for DFT calculation. According to ④ and ①,

which is

This is the calculation formula for the minimum range resolution that FMCW can obtain when the frequency modulation bandwidth is determined.

In actual use, the sampling time will be slightly shorter than the actual frequency modulation T. That is, Fres will be larger in value. So Sres will also become larger in value.

FMCW vs Pulse radar

VEGAPULS has a good explanation video about PULSE and FMCW technology | Radar level measurement. Let’s take a look together.

Video source: https://www.youtube.com/watch?v=eAngy1B1FP

Pulse Radar

Pulse radar is a precision tracking radar. Each time it emits a pulse, the antenna can form several beams at the same time, and compare the amplitude and phase of the echo signal of each beam.

When the target is located on the antenna axis, the amplitude and phase of the echo signal of each beam are equal, and the signal difference is zero.

When the target is not on the antenna axis, the amplitude and phase of the echo signals of each beam are not equal, resulting in signal difference.

Drive the antenna to the target until the antenna axis is aligned with the target, so that the high and low angle and azimuth angle of the target can be measured.

The sum of the signals received by each beam can measure the distance of the target. In order to realize the measurement and tracking of the target.

FMCW

FM continuous wave radar refers to a continuous wave radar whose transmitting frequency is modulated by a specific signal, such as weather radar.

FM continuous wave radar obtains the distance information of the target by comparing the difference between the frequency of the echo signal at any time and the frequency of the transmitted signal at that time.

The distance is proportional to the frequency difference between the two. The radial velocity and distance of the target can be obtained by processing the measured frequency difference between the two.

Compared with other range and speed measurement radars, the structure of FM continuous wave radar is simpler.

FMCW radar has rich technical experience, low transmit power peak required, easy modulation, low cost, and simple signal processing, so it is a commonly used radar system in automotive radars.

LFMCW radar, i.e., the carrier signal frequency changes linearly with time.

FAQ

What is frequency modulated continuous wave?

FM continuous wave radar refers to a continuous wave radar whose transmitting frequency is modulated by a specific signal.
The principle of frequency modulated continuous wave (FMCW) radar is to send a continuous signal with a certain bandwidth and linear change in frequency, and then perform fast Fourier transform on the received continuous signal.
The time difference between the two signals is calculated by the frequency difference between the sending and receiving signals. Finally, like the pulse wave radar level meter, the corresponding distance value is obtained from the time difference.
FMCW radar can obtain very high accuracy, and its accuracy mainly depends on the linearity and temperature drift of the voltage controlled oscillator.

What does continuous wave mean?

continuous wave or continuous waveform (CWis an electromagnetic wave of constant amplitude and frequency, typically a sine wave, that for mathematical analysis is considered to be of infinite duration.

What does Fmcw stand for?

FMCW is short for Frequency Modulated Continuous Wave.

Sino-Inst offers over 10 FMCW Radar Level Transmitters for level measurement. About 50% of these are float liquid level meters, 40% is the Solid level sensors.

A wide variety of FMCW Radar Level Transmitters options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of FMCW Radar Level Transmitters instrumentation, located in China.

Request a Quote

Please enable JavaScript in your browser to submit the form

SI-FMF11 FMCW Radar Level Transmitter 120GHz

FMCW Radar Level Transmitter with 120GHz fmcw, IP67 anti, can carry out 0.05m~30m Non-contact level measurement.

FMCW Radar Level Transmitter with 120G fmcw, IP67 anti, can carry out 0.05m~30m level measurement.
FMCW Radar Level Transmitter is based on the principle of FM continuous wave. FMCW refers to frequency modulated continuous wave. Use chirp high frequency signal.
120GHz FMCW Radar Level Transmitter, measuring distance up to 30 meters. The antenna is further optimized. The new and fast microprocessor can perform higher rate signal analysis and processing. The Radar Level Transmitter can be used for measuring high temperature and high pressure and other environmental liquids.

Sino-Inst offers a variety of FMCW Radar Level Transmitters for industrial level measurement. If you have any questions, please contact our sales engineers.

Features of SI-FMF11 FMCW Radar Level Transmitter

  • Millimeter wave radar. The measurement accuracy is up to ±2mm. The minimum blind area for measurement is 0.05m.
  • The smaller antenna size satisfies the measurement of more working conditions.
  • Multiple lens antennas. Smaller launch angle. More concentrated energy. Stronger echo signal. Under the same working conditions, it has higher reliability than other radar products.
  • It has stronger penetrability. It can be used normally in the case of adhesion and condensation.
  • Larger dynamic signal range. The measurement of low-dielectric constant medium is more stable.
  • Multiple measurement modes. The radar response time in fast measurement mode is less than 1s.

Specifications of SI-FMF11 FMCW Radar Level Transmitter

Measuring medium:Liquid
Measuring range:0.05m~30m
Process connection:G1 ½A/1½NPT thread/flange≥DN50
Process temperature:-40~80℃
Process pressure:-0.1~0.3 MPa
Accuracy:±2mm
Protection level:IP67
Frequency Range:123GHz
power supply:Two-wire system (DC24V) / Four-wire system (DC12V~24V) / Four-wire system (AC220V)
Explosion-proof grade:Exia ⅡC T6 Ga / Exd IIC T6 Gb
Housing:Aluminum/plastic/stainless steel
Signal output:Two-wire system 4…20mA/HART protocol Four-wire system 4…20mA/RS485 Mod bus

FMCW Radar Level Transmitter 120GHz Applications

Solid measurement

  • Powder
  • Granule
  • Block
  • ※ Low dielectric constant plastic particles

Liquid measurement

FMCW

What does Fmcw stand for?

FMCW, namely Frequency Modulated Continuous Wave.

FMCW technology and pulse radar technology are two technologies used in high-precision radar ranging. The basic principle is that the transmitted wave is a high-frequency continuous wave. Its frequency changes with time according to the law of triangle wave.

FMCW (Frequency Modulated Continuous Wave), the received echo frequency and the transmitted frequency change law are the same, both are triangular waves. There is only a time difference. Using this tiny time difference, the target distance can be calculated.

Extended Reading: Case: High Temperature Radar Level Transmitter for Melted Salt-Solar Photovoltaic Power Station

FMCW Radar Level Transmitter Working Principle

FM wave radar level sensor and distance formula:

Among them: C speed of light; fd Doppler frequency shift; fu triangle rising edge difference frequency; f0 FM initial frequency; T signal period; B signal bandwidth

The distance resolution depends on the frequency resolution of the DFT operation (Frequency Resolution). The frequency resolution of the DFT Fres is equal to:

 

T is the corresponding sampling time of the non-zero sampling value used for the DFT operation. If you use FFT + zero padding method to calculate the spectrum. T is the time corresponding to the sampled value of the non-zero-filled point.

The distance corresponding to the frequency resolution Fres is the range resolution Sres of the radar. Then, how to calculate the range resolution of the FMCW radar?

B: Frequency modulation width, unit Hz

T: Actual frequency modulation, in seconds

C: Speed of light, 3*10^8 meters/second

S: the distance between the radar and the object, meters

V: Frequency modulation speed, Hz/sec

t: wave propagation time, sec

V=BW/T  ②

t= 2S/C   ③

Assume that T is sampling during the entire frequency modulation period. And all sampling points are used for DFT calculation. According to ④ and ①,

which is

This is the calculation formula for the minimum range resolution that FMCW can obtain when the frequency modulation bandwidth is determined.

In actual use, the sampling time will be slightly shorter than the actual frequency modulation T. That is, Fres will be larger in value. So Sres will also become larger in value.

LFMCW, FMCW and Pulse radar

Radar (Radio detecting and ranging) means radio search and ranging. It is a device that uses various radio positioning methods to detect and identify various targets, determine target coordinates and other information.

In modern military and production, the role of radar is increasingly showing its importance. Especially in the Second World War, the “British” air battle between the British Air Force and the Luftwaffe made the importance of radar very clear.

The radar is composed of antenna system, transmitting device, receiving device, anti-interference equipment, display, signal processor, power supply and so on. Among them, the antenna is one of the key technologies for radar to achieve large airspace, multi-function, and multi-target. The signal processor is one of the core components of the radar with multi-function capabilities.

There are many types of radars, which can be classified in many ways:
(1) According to the positioning method, it can be divided into: active radar, semi-active radar and passive radar.
(2) According to the installation location, it can be divided into: ground radar, shipborne radar, aviation radar, satellite radar, etc.
(3) According to the type of radiation, it can be divided into: pulse radar and continuous wave radar.
(4) According to the work, it can be divided into long wave bands: meter wave radar, decimeter wave radar, centimeter wave radar and other wave band radars.
(5) According to the purpose, it can be divided into: target detection radar, reconnaissance radar, weapon control radar, flight support radar, weather radar, navigation radar, etc.

Pulse Radar

Pulse radar is a precision tracking radar. Each time it emits a pulse, the antenna can form several beams at the same time, and compare the amplitude and phase of the echo signal of each beam.

When the target is located on the antenna axis, the amplitude and phase of the echo signal of each beam are equal, and the signal difference is zero.

When the target is not on the antenna axis, the amplitude and phase of the echo signals of each beam are not equal, resulting in signal difference.

Drive the antenna to the target until the antenna axis is aligned with the target, so that the high and low angle and azimuth angle of the target can be measured.

The sum of the signals received by each beam can measure the distance of the target. In order to realize the measurement and tracking of the target.

FMCW

FM continuous wave radar refers to a continuous wave radar whose transmitting frequency is modulated by a specific signal, such as weather radar.

FM continuous wave radar obtains the distance information of the target by comparing the difference between the frequency of the echo signal at any time and the frequency of the transmitted signal at that time.

The distance is proportional to the frequency difference between the two. The radial velocity and distance of the target can be obtained by processing the measured frequency difference between the two.

Compared with other range and speed measurement radars, the structure of FM continuous wave radar is simpler.

FMCW radar has rich technical experience, low transmit power peak required, easy modulation, low cost, and simple signal processing, so it is a commonly used radar system in automotive radars.

LFMCW radar, i.e., the carrier signal frequency changes linearly with time.

80G radar level sensor refers to frequency modulated continuous wave (FMCW) radar products working at 76-81GHz. It supports four-wire and two-wire applications. The large range of the product can reach 150m. The blind area can reach 8cm.

Because of its higher operating frequency and shorter wavelength, it is especially suitable for solid-state applications. It transmits and receives electromagnetic waves through a lens. It has unique advantages in high dust and harsh temperature environments (+200°C).

The main advantages of 80G high frequency radar level sensor are as follows:

  1. Based on self-developed CMOS millimeter-wave radio frequency chip. Realize a more compact radio frequency architecture. Higher signal-to-noise ratio and smaller blind area.
  2. Narrow 3° antenna beam angle. The interference in the installation environment has less influence on the instrument, and the installation is more convenient.
  3. The wavelength is shorter. It has better reflection characteristics on the solid surface. Therefore, there is no need to use a universal flange for aiming.
  4. Support remote debugging and remote upgrade. Reduce waiting time. Improve work efficiency.
  5. Support mobile phone Bluetooth debugging. It is convenient for on-site personnel to maintain work.

VEGAPULS 64 is a radar sensor for continuous level measurement of liquids. VEGA is the world’s leading manufacturer of radar level sensors. 80GHz radar level gauge VEGAPULS 64 has excellent performance.

Following VEGA, Sino-Inst also launched radar level sensor operating at 76-81 GHz.

The radar level sensor is divided according to the antenna type. There are the following types:
Cone antenna, parabolic antenna, horn antenna, long horn antenna.

The horn antenna adopts the working method of transmitting radar waves from a single point.
After the reflection of the horn surface, a divergent radar wave is formed. Usually used to measure the level of the vaulted tank that does not require a conduit. The measurement distance is smaller than that of a parabolic antenna.

Since the entire horn antenna extends into the tank, there is no big difference with the temperature in the tank. Therefore, there is basically no condensation on the antenna.

Guided wave radar level transmitter uses guided wave radar (GWR) technology. Based on the reflection of microwave on the surface medium. Through the probe, continuous level measurement of liquid and solid levels is completed.

A guided wave radar level transmitter is also called a wave-guided radar level sensor. They can measure both levels and the interface between two media. Through probe rod or cable, complete level contact types continuous level measurement. Such as Coaxial Probe Guided Wave Radar Level Transmitter. This is different from ultrasonic level measurement, which is non-contact measurement. A guided wave radar level transmitter is often used for tank level measurement. Including liquid and solid. Output 4~20mA/HART, so as to measure and control the level during production.

Extended reading: guided wave radar level sensor advantages and disadvantages

Ultrasonic Level Sensing sensors and transmitters are used for continuous, non-contact level measurement.

Ultrasonic Level Sensing is a low-cost liquid level measurement technology. Ultrasonic Level Sensing sensors and transmitters are used for tank or river level measurement. Ultrasonic Level Sensing does not need to contact the medium, can be continuously measured, low cost. Therefore, Ultrasonic Level Sensing is very popular among users. Ultrasonic liquid level sensors are available in general and intrinsically safe types. Output 4~20mA standard signal or output the measurement result to the secondary meter through RS-485. Meets the system’s automatic control.

More Featured Radar Level Transmitter

Frequently
Asked
Questions

Radar level transmitter is an advanced non-contact measuring instrument. It is suitable for solid materials, process containers or strong dusts that are prone to crystallization and condensation. It has the advantages of low maintenance, high performance, high precision, high reliability and long service life.

It can adapt to harsh production environments such as high temperature, high pressure and steam. Even under extreme process conditions (pressure, temperature) and steam. Radar level measurement is also a safe solution.

Radar level transmitters can also be used in hygienic applications for non-contact level measurement.

Radar level transmitter versions can be used in different industries such as water/wastewater, food industry, life sciences or process industries.

Various antenna versions are available for various radar applications.

Radar Level Measurement and guide wave radar level measurement Image source: https://instrumentationtools.com/radar-level-measurement/

Very short microwave pulses with very low energy are transmitted and received through the antenna system. The radar wave runs at the speed of light. The operating time can be converted into level signals by electronic components. A special time extension method can ensure stable and accurate measurement in a very short time.

Electromagnetic waves propagate in the air at the speed of light. The distance between the radar level gauge and the surface of the material can be expressed by the following formula:   

D = (1/2)*CT

In the formula:

D ———the distance between the radar level gauge and the surface of the material;   

C ———Speed of light   

T ———Pulse time.

Then the liquid level is:   L = E-D

In the formula:

L — liquid level;   

E ———The total height of the tank;   

D ———Air height.

Even in the presence of false reflections, the new micro-processing technology and the unique ECHOFOX- software can accurately analyze the level echo. By inputting the size of the container, the distance value can be converted into a signal proportional to the level. The instrument can be debugged with empty positions.

The radar is calibrated before leaving the factory. The wall can be tested before installation. The measured distance matches the measured distance.

There is also a test method, which is to send the 4-20mA value in the programmer to see if it is consistent with the value in the control room. After the test is completed, it will return to the normal test state from the power off.

Different settings in various mines.
Such as water, set it to liquid in the settings. There is almost no need to set other parameters.
If it is powder, then set the solid, cutting speed, material change, etc.
Adjust the universal joint flange;

Sino-Inst offers over 10 FMCW Radar Level Transmitters for level measurement. About 50% of these are float liquid level meters, 40% is the Solid level sensors.

A wide variety of FMCW Radar Level Transmitters options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of FMCW Radar Level Transmitters instrumentation, located in China.

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Stable And Reliable Sheathed Thermocouple

Sheathed thermocouple have the advantages of bending, high pressure resistance, fast thermal response time and durability.

Sheathed thermocouple can directly measure the temperature of liquid, steam and gaseous media and solid surfaces in the range of 0℃~1200℃ in various production processes.

Sheathed thermocouples are usually used along with display instruments, recording instruments, electronic computers and so on. It is able to directly measure the temperature of liquid, steam and gas and solid surface in a variety of production processes within the range of 0 ~1300℃.

Sino-Inst offers a variety of Sheathed Thermocouple . If you have any questions, please contact our sales engineers.

Advantages

  1. Less thermal response time,which can reduce the dynamic error.
  2. Flexible mounting for use.
  3. Wide measuring scope.
  4. High mechanical strength and good pressure resistance.

There are actually many techniques for using sheathed thermocouples.

  • It has bendable performance. The thermal resistance of the sheath can be bent in any direction . except for the head, so it is suitable for the temperature of the complicated structure and small equipment.
  • The sheathed thermocouple has good vibration and impact resistance. Therefore, its life is longer than ordinary thermal resistance.
  • The sheathed thermocouple has a long service life. Because the resistance body of the sheathed thermal resistance is maintained by the metal sleeve, the thermal resistance wire is not easily corroded by harmful media.
  • It is suitable for measuring in strong alkali and corrosive medium. with a temperature resistance of 250℃, and the fixed installation situation can also use the same PTFE fixed thread.
  • According to the measurement temperature range and side measurement object, select the appropriate thermal resistance model, specification and maintenance tube information.

What Is Sheathed Thermocouple?

Sheathed thermocouples consist of an outer metallic sheath, which contains the insulated internal leads, embedded within a high-density ceramic compound (mineral-insulated cable, also called MI cable). Sheathed thermocouples are bendable and may be bent to a minimum radius of five times the sheath diameter.

Learn more about Thermocouple from Wikipedia.

What Are The Types Of Sheathed Thermocouple?

Sheathed thermocouples have different types. Type J, K, T, & E are “Base Metal” thermocouples, the most common types of thermocouples. Type R, S, and B are “Noble Metal” thermocouples, which are used in high temperature applications (see thermocouple temperature ranges for details)

ModelGraduationRange of temperature
 measurement ℃ —–I
Tolerance value—-IRange of temperature
measurement ℃—II
Tolerance value—-II
WRNKK-40~+375±1.5℃-40~+333±2.5℃
WRNKK375~1000±0.004ltl333~1200±0.0075ltl
WRNKN-40~+375±1.5℃-40~+333±2.5℃
WRNKN375~1000±0.004ltl333~1200±0.0075ltl
WRNKE-40~+375±1.5℃-40~+333±2.5℃
WRNKE375~800±0.004ltl333~900±0.0075ltl
WRNKJ-40~+375±1.5℃-40~+333±2.5℃
WRNKJ375~750±0.004ltl333~750±0.0075ltl
WRNKT-40~+125±0.5℃’-40~133±1.0℃
WRNKT125~350±0.004ltl133~350±0.0075ltl
WRNKS0~+1100±1.0℃0~600±1.5℃
WRNKS1100~1600±[1+0.003(t-1100)]600~1600±0.0025ltl
WRNKR0~1000±1.0℃0~600±1.5℃
WRNKR1100~1600±[1+0.003(t-1100)]600~1600±0.0025ltl
WRNKB————600~1700±0.0025ltl
WRNKB——————

Extended reading:  Tri Clamp Sanitary Thermometers

Can You Overheat a Sheathed Thermocouple?

  • In terms of the sheath thermocouple, the environment temperature is 20 + 15℃, the relative humidity is not more than 80%, the test voltage is 500 + 50V(DC), the insulation resistance between electrode and outer sleeve≥1000MΩ.m.
  • That is to say, the insulation resistance for sample of 1m is 1000MΩ;
  • the insulation resistance for sample of 10m is 100MΩ.

Sheathed Thermocouple’s Working Principle

The electrode of sheath thermocouple are consisted by two different materials of conductor. When there is a temperature difference between the measuring end and the reference end, it will generate the thermal electric potential. The working instrument will show the corresponding temperature value of the thermal electric potential.

How Do You Identify A Sheathed Thermocouple?

If the flame ignites and goes out when you release the gas control knob after holding it in for the recommended 20 to 30 seconds, that’s the sign of a thermocouple malfunction. Before jumping to the conclusion that the thermocouple is at fault, look at the pilot flame.

More Featured Temperature Transmitters

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External Ultrasonic Tank Level Sensor

The external ultrasonic tank level sensors is the first choice for measuring liquid level and material level on various industrial tanks.

The intelligent ultrasonic tank level sensor installs the ultrasonic probe directly under the tank when measuring. No need to open holes, easy to install. Does not affect on-site production. It can measure various toxic substances and pure liquids in high temperature and high pressure airtight containers. The instrument adopts explosion-proof design to meet explosion-proof requirements. The Internet of Things can be realized through GPRS and Wifi.

Sino-Inst offers a variety of  ultrasonic level meters for tank level measurement. If you have any questions, please contact our sales engineers.

Features of External Ultrasonic Tank Level Sensor

  • The probe is external, no need to open a hole to the container under test.. Really realize non-contact measurement.
  • It is suitable for accurate measurement of the liquid level of toxic, volatile, flammable, explosive, and highly corrosive liquid media in various closed containers.
  • The instrument has no mechanical moving parts and has a long life. No corrosion, no pollution, wide use area.
  • The instrument has built-in ASIC (Intelligent Ultrasonic Special Hardware Integrated Circuit), which makes the instrument small in size, stable and reliable in measurement results. It can be suitable for all kinds of liquids and containers to be tested, and it is easy to install on site without complicated on-site calibration.
  • The instrument has built-in various calibration functions such as automatic temperature correction and automatic fixed distance calibration. The measurement results are more accurate and reliable.
  • The instrument has complete functions, with RS485 output, 4-20mA output, and switch output.
  • Multiple power supply methods available
  • Backup and restore configuration parameters
  • The analog output can be adjusted arbitrarily
  • With digital filtering and echo recognition functions
  • Fixed interference filtering function can be manually set
  • Support Bluetooth, GPRS communication, GPS satellite positioning, etc. (Order to buy)
  • Support custom serial data format
  • Support custom main display interface
  • Support MiniSD card data collection (order option)

Extended reading: The Secret of Ultrasonic Level Measurement

Technical Parameter of External Ultrasonic Tank Level Sensor

Range1m, 3m, 5m, 8m, 10m, 15m, 20m, 25m, 30m
Accuracy±1mm-±0.3%FS
different from the sensor, too thick tank wall, unstable pressure and temperature may affect accuracy
DisplayChinese and English large screen LCD, color screen TFT (optional)
Display resolution1MM
Output4~20mA (maximum load 350Ω), RS485, switch value, TF card, GPRS, GPS
Power supplyDC12-24V or AC220V
Shell materialcast aluminum
Protection levelIP65
Probe materialABS
Installation methoddirect magnetic adsorption or adhesive transfer sheet (ferromagnetic), then magnetic adsorption
Sensor outlet cablewith standard 10M (optional length, optional sensor cable sheath)
Dimensionshost 230X210X129/135X180X86
Electrical interface specificationM20X1.5
Diameter of threading hole5-15mm
MaterialCopper plating
Power inlet cable10m (optional length)
Ambient temperature of the host-20℃~+70℃
The ambient temperature of the ultrasonic probe-40℃~+100℃
Humidity15%~100% RH

Extended reading: Guide to Ultrasonic Level Transmitters

Application Industry:

  1. Pharmaceutical manufacturing industry: liquid level control of reaction liquid in pipelines and storage tanks, etc.
  2. Petrochemical industry: oil pipeline, internal liquid level control of storage tanks, etc.
  3. Food industry: liquid level detection and monitoring projects in brewing, beverage, milk production, storage tanks, pipelines, etc.

Read more about: 7 Level Senors for Tank Level Measurement

Application Conditions:

Media Purity

the liquid cannot be filled with dense bubbles. A large amount of solids, such as crystals, cannot be suspended in the liquid.The bottom of the container cannot deposit a large amount of sand and sediment.

Medium Viscosity

When the dynamic viscosity is less than 10mPaS, it is measured normally. When 10mPaS<dynamic viscosity<30mPaS, the range of the instrument may be reduced. It cannot be measured when the dynamic viscosity is >30mPaS.

note: As the temperature increases, the viscosity decreases, and most high-viscosity liquids are more affected by temperature. Therefore, pay attention to the effect of liquid temperature when measuring viscous liquids.

Container Under Test

  1. Material: The container wall where the measuring probe is installed is required to be made of hard materials that can transmit signals well. Examples: carbon steel, stainless steel, various hard metals, glass steel, hard plastics, ceramics, glass, hard rubber and other materials or their composite materials. If the container wall where the measuring probe is installed is of multilayer material, the layers should be in close contact with no bubbles or gas interlayers. The inner and outer surfaces of the container wall should be flat. Examples: vulcanized hard rubber lining, stainless steel lining, titanium lining Floor.
  2. Wall thickness: 1-100mm
  3. Tank type: spherical tank, horizontal tank, vertical tank, etc.

Probe Installation Requirements:

  1. For iron containers, you can apply silicone grease to the working end of the probe and stick it directly to the bottom of the container with a magnetic suction cup; if the container shell is made of glass or other materials, you can use glue to fix the probe or use a bracket to fix it. The bottom of the container. The probe point must be on the same straight line as the measured distance.
  2. There are no obstructions such as coils directly above the probe;
  3. Keep away from the liquid inlet at the bottom of the tank to avoid the influence of the violent flow of the liquid on the measurement;
  4. Keep away from the position below the liquid inlet on the top of the tank to avoid the impact of the liquid inlet and the violent fluctuation of the liquid level to affect the measurement;
  5. It is higher than the liquid outlet or the sewage outlet to avoid the influence of long-term deposits on the bottom of the tank on the measurement. If the conditions are not met, measures should be taken to ensure that the bottom of the tank is regularly removed;
  6. When the liquid level measuring head is installed by magnetic or welding/adhesive fixing method, the installation surface size on the container wall should not be less than the round surface of Ф80, the surface roughness should reach 1.6, and the inclination should be less than 3°(bypass pipe exce

What Is External Ultrasonic Tank Level Sensor?

Ultrasonic level meter is a high-tech product that integrates ultrasound, electronics and software. The various indicators of the ultrasonic level meter have reached the advanced level of similar products in the world. and it is the first-choice instrument for measuring liquid level and material level on various industrial sites.

How Do External Ultrasonic Tank Level Sensors Work?

Install the ultrasonic probe directly below the outer wall of the container under test. No need to open holes, easy to install, and does not affect on-site production. It can accurately measure various toxic substances and various pure liquids in high temperature and high pressure airtight containers.The instrument has built-in ASIC (Intelligent Ultrasonic Special Hardware Integrated Circuit), which makes the instrument small in size, stable and reliable in measurement results, and can be suitable for various liquids and containers to be tested. It is easy to install on site and does not require complex on-site calibration.

The instrument has built-in various calibration functions such as automatic temperature correction and automatic fixed distance calibration to make the measurement results more accurate and reliable. The Internet of Things can be realized through GPRS and Wifi.

How Do You Mount An External Ultrasonic Tank Level Sensor?

The probe is installed externally, no need to open a hole in the container to be tested, and truly realize non-contact measurement.It is suitable for accurate measurement of the liquid level of toxic, volatile, flammable, explosive, strong pressure, strong corrosive and other liquid media in various closed containers.The instrument has no mechanical moving parts and has a long life. No corrosion, no pollution, wide use area.

What Are The Benefits?

  1. Safe : No valves, connecting pipes, joints, no leaks, no contact with the liquid and gas in the tank, very safe, when measuring toxic, corrosive, pressure, flammable, volatile, and easy to leak liquids
  2. Hygiene: liquid level detection and monitoring projects in brewing, beverages, milk production, storage tanks, pipelines, etc. do not come in contact with liquids and cause pollution.
  3. Convenient installation and maintenance: no fire or tank cleaning during installation and maintenance will not affect production.

Read more: Guide: Non-contact Ultrasonic Level Sensing transmitters

When measuring the External Ultrasonic Tank Level Sensor, install the ultrasonic probe directly under the outer wall (bottom) of the container under test. No need to open holes, easy to install, and does not affect on-site production. It can be used to treat various toxic substances in high temperature and high pressure airtight containers. Accurate measurement of a pure liquid.

The External Ultrasonic Tank Level Sensor adopts explosion-proof design to meet explosion-proof requirements. The probe is installed externally, no need to open a hole in the container to be tested, real non-contact measurement, suitable for accurate liquid level of toxic, volatile, flammable, explosive, strong pressure, strong corrosive and other liquid media in various closed containers measuring.

The External Ultrasonic Tank Level Sensor has no mechanical moving parts and has a long life. No corrosion, no pollution, wide use area. More about Top 5 Ultrasonic Level Sensor Applications.

In the design work, a reasonable and optimized External Ultrasonic Tank Level Sensor selection scheme was made according to each project. Judging from the production and application, the effect is very good.

1.Field application of butadiene

In a rubber project, it is necessary to measure the level of butadiene in the spherical tank. Butadiene is prone to self-polymerization to produce high molecular polymers, and the selection of ordinary liquid level meters is limited. According to the requirements of “Tank Area Automation System Design Regulations”, “Each pressure storage tank should be equipped with two sets of independent and different types of liquid level measuring instruments”. If the conventional contact liquid level gauge is selected for this project, butadiene is at the dead corner of the detection port The possibility of self-aggregation is very large, so the non-contact type should be given priority to the selection of the level gauge. Finally, a set of non-contact radar level gauges were installed on the top of the tank, and a set of External Ultrasonic Tank Level Sensors were installed on the bottom of the tank. After the field application, the externally attached ultrasonic level gauge measures accurately and the effect is very good.

2.Field application of liquid ammonia

In the design of a certain liquid ammonia spherical tank, the External Ultrasonic Tank Level Sensor also has a good application. The liquid ammonia in the storage tank is a colorless, pungent odor and toxic liquid, which is corrosive to a certain extent. Because the density of liquid ammonia is greatly affected by temperature, the differential pressure level gauge is not applicable in this project, and the external ultrasonic level gauge is finally used for detection.

3.Field application of high pressure storage tank

In a high-pressure hydrogenation plant, due to the unstable parameters of the original level gauge on the high-pressure storage tank, the owner wanted to add a level gauge to compare with it. However, the installation space of the high-pressure vessel was small on site, and the conditions for reopening were not available. After negotiation, it was decided to adopt an external ultrasonic level gauge, which not only avoided the economic loss caused by the shutdown of the device, but also prevented new pressure vessels. Increase the safety hazards of leakage points, simple installation, accurate and reliable, can be described as three birds with one stone.

4.Ultrasonic sensor for Oil/fuel level measurement

The External Ultrasonic Tank Level Sensor adopts explosion-proof design to meet explosion-proof requirements. The probe is installed externally, no need to open a hole in the container to be tested, real non-contact measurement, suitable for accurate liquid level of toxic, volatile, flammable, explosive, strong pressure, strong corrosive and other liquid media in various closed containers measuring. Therefore, the External Ultrasonic Tank Level Sensor is the best level measurement sensor for diesel, gasoline and other oil tanks. More about Diesel Fuel Level Sensor Types.

5. Other field applications

The External Ultrasonic Tank Level Sensor can be a good substitute for radar level gauges in some occasions where the dielectric constant is low, such as liquefied gas (dielectric constant <1.9) or the liquid surface contains a lot of bubbles and other radar level gauges are not suitable for use; For some highly corrosive acid and alkali storage tanks, such as liquid chlorine storage tanks, the External Ultrasonic Tank Level Sensor is also very useful.

External Ultrasonic Tank Level Sensor common available media include liquid chlorine, liquefied gas, liquid ammonia, ethylene, butadiene, gasoline, diesel, benzene, liquid bromine, hydrochloric acid, lye, nitric acid, methanol, vinyl chloride, hydrofluoric acid, ethylene Glycol, propane, naphtha, ethylene oxide, dimethyl ether.

Extended reading: ultrasonic level sensor for diesel tank

Can External Ultrasonic Tank Level Sensors Detect Water Level?

Ultrasonic liquid level sensor can be used for water level measurement. The principle of ultrasonic reflection used. According to the contact between the sound wave emitted by the pool ultrasonic liquid level gauge and the liquid surface. According to the length of time it reflects back. To measure the height of the liquid level in the tank.
Liquid level sensors are used in many sites to detect some conditions that require liquid level monitoring. It is well known that the liquid level of some sewage treatment tanks, the liquid level on the tank, the liquid level on the river channel and so on.

What is an ultrasonic level sensor?

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.

What are the different types of level sensors?

There are 7 main types of level transmitters that Sino-Inst offers for water level indicate. 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

Read More About: Explosion Proof Ultrasonic Level Sensors Operating Principle.

Related products and technologies

More Tank Level Measurement Solutions

Read more about: Ultrasonic Level Sensors for Liquids Applications

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

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

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

Request a Quote

Please enable JavaScript in your browser to submit the form

SIRD-705 GWR Level Sensor for High Temperature & High Pressure

High Temperature & High Pressure level measurement, SIRD-705 GWR Level Sensor is a good choice. The highest pressure reaches 40MPa, and the highest temperature reaches 400℃.

The high temperature and high pressure guided wave radar level sensor is specially designed for high temperature and high pressure occasions. The product is mainly used for liquid level measurement on various boiler drums. Has high safety and accuracy. The highest rated pressure reaches 40MPa. The highest rated temperature reaches 400℃. It is suitable for high and low pressure heaters, condensers and deaerators in thermal power plants. As well as for liquid level measurement under high temperature, high pressure, vacuum and other steam conditions.

Sino-Inst offers a variety of Guided wave radar Level Sensors for industrial high temperature and high pressure level measurement. If you have any questions, please contact our sales engineers.

Features of GWR High Temperature Liquid Level Sensor

GWR Level Sensor has the advantages of low maintenance, high performance, high precision, high reliability and long service life. Compared with contact instruments such as capacitors and heavy hammers, it has unparalleled advantages.

The transmission of microwave signals is not affected by the atmosphere. Therefore, it can meet the requirements of harsh environments such as volatile gases, high temperature, high pressure, steam, vacuum and high dust in the process.

GWR Level Sensor is suitable for harsh environments such as high temperature, high pressure, vacuum, steam, high dust and volatile gases. It can continuously measure different material levels.

The main technical indicators of GWR Level Sensor meet or exceed similar products at home and abroad. It is easy to install and debug. It can be used alone or in a network. It can be widely used in metallurgy, building materials, energy, petrochemical, water conservancy, food and other industries.

GWR Level Sensor measurement advantages:

  • It has a strong ability to suppress steam and foam, and the measurement is not affected;
  • Not affected by liquid density, loose degree of solid material, temperature, and dust during feeding;
  • Low maintenance, high performance, high precision, high reliability and long service life.

Specifications of SIRD-705 GWR Level Sensor for High Temperature & High Pressure

Suitable for Medium: Liquids, especially high temperature and pressure environment of liquid
Application: Sealed tanks, high pressure liquid measurement 
Explosion-proof Grade: Exia IIC T6 Ga/Exd IIC T6 Gb  Measuring 
Range: 15m 
Frequency: 500MHz-1.8GHz
Antenna: Single cable or single rod antenna 
Accuracy: ±10mm
Process Temperature:(-200~400)℃
Process pressure:(-0.1~40)MPa
Signal output:(4~20)mA/HART
The Scene Display: Four LCD/Can be programmed
Power Source: Two-wire (DC24V) 
Four-wire(DC24V/AC220V)
Shell: Aluminum /Plastic
Connection:  Thread / Flange (optional)

GWR Level Sensor for High Temperature & High Pressure Applications

SIRD-705 GWR Level Sensor is suitable for measuring liquids with high pressure in sealed tanks, especially liquids in high temperature and high pressure environments.

It is suitable for high-pressure bubble water level measurement in power plants, liquid ammonia measurement, and liquid level measurement in chemical fertilizer synthesis ammonia process.

Advantages of using guided wave radar level sensors on boilers

Guided wave radar level sensor is often used in industrial production. Because of its superior performance, it is accepted by the public. It has the advantages of low maintenance cost, strong detection performance, accurate measurement accuracy, high safety, and long service life. The signal emitted by the device is not affected by the environment, atmosphere. So it can be used in a variety of special media, such as high temperature, high pressure, steam state, volatile gas, dust, vacuum environment, etc.

Guided wave radar level sensors in boilers

Today I want to share with you how to use the guided wave radar level sensor in the boiler. The high temperature and high pressure in the boiler need to use the level sensor to measure the internal liquid level to ensure its safety. The use of guided wave radar level sensors can solve the difficult problems of safety, accurate readings, and simple maintenance.

On some boilers, each boiler installation requires at least two independent water level sensors. Therefore, each boiler also needs to be equipped with two guided wave radar level sensors. Only in this way can the safety requirements for boiler operation be fully met. Guided wave radar level sensors need to use quartz tubes to observe changes in the liquid level in the furnace. However, the connecting pipes and valves need to be opened to improve the accuracy of detection. It is necessary to ensure that the probe and sensor are dry and clean during installation. If contamination occurs, it can not be wiped with a wet towel, and alcohol must be used for decontamination.

Although many cities do not yet have standard regulations on boiler level sensors. At least one intuitive level sensor must be installed, together with a guided wave radar level sensor for observation. If it is a large and complex complete set of boiler equipment, it is necessary to redesign and plan the guided wave radar level sensor and install it according to the design drawing.

If you need to measure river water level, open channel level, etc. The Ultrasonic Liquid Level Sensor can be used for non-contact continuous level monitoring.

Boilers usually use at least 2~3 sets of liquid level display systems according to their different sizes and uses. The selection of Level Transmitter is also different according to different requirements.

  1. Direct liquid level display. The purpose is to observe the liquid level most intuitively. Commonly used plate level gauges, two-color level gauges, and magnetic flap level gauges are also commonly used on low-pressure and small-tonnage boilers;
  2. Control Level Transmitter. It is used for automatic control signals. Usually a balance chamber is used to match a differential pressure transmitter. Immersion float level gauges are also commonly used. This type of level gauge requires the measurement principle to be directly related to the density of the medium to avoid boilers False liquid level effects;
  3. Level Transmitter for safety. Electric contact water level gauge is mostly used. Its characteristic is to indicate the liquid level point by point. The points are not related to each other. Breaking a few points does not affect the display of other points. The reliability is extremely high.

The Non Contact Liquid Level Sensor is not in contact with the measured medium. The Non Contact Liquid Level Sensors provided by Sino-Inst is not Gravity Non-contact Liquid Level Sensors. It is the liquid level sensor used in industrial tanks, reservoirs, and open channels. There are mainly ultrasonic level sensors and radar level sensors.

The measurement temperature of most Ultrasonic Level Sensors currently on the market is -20 to +80°C.

So, can Ultrasonic Level Sensor measure high temperature and high pressure?
The answer is no.

One customer was affected by high temperature using E+H Ultrasonic Level Sensor.

The ultrasonic level gauge can measure when the water surface is close to the probe, but cannot measure when the water surface is far from the probe. When the water temperature is low, the ultrasonic level gauge measures normally, but when the water temperature is high, the ultrasonic level gauge cannot measure. This is the measurement of the high temperature inside the pool or tank on site that affects the ultrasonic level gauge.

The reason why the E+H ultrasonic level gauge has this problem is that the liquid medium generally does not produce steam and mist below 30-40 °C. Above this temperature it is easy to generate steam or mist.

The ultrasonic wave emitted by the E+H ultrasonic level gauge will attenuate once as it passes through the steam during transmission. Attenuates again when reflected back from the liquid surface. As a result, the weak ultrasonic signal returns to the probe at the end and cannot be measured.

Moreover, in this environment, the probe of the ultrasonic level gauge is prone to form water droplets. It will hinder the transmission and reception of ultrasonic waves.

To solve this problem, we can have the following two operation options:

  1. To increase the measurement range, the height of the water tank is actually 3 meters. The E+H ultrasonic level gauge between 6 meters and 9 meters should be selected. The effect of steam or fog on the measurement can be reduced or reduced.
  2. The probe of E+H ultrasonic level gauge should be made of polytetrafluoroethylene or PVDF. Physically sealed. In this way, water droplets are not easy to condense on the emitting surface of the probe. As for the emitting surface of other materials, water droplets can easily condense.

High Temperature Level Switch refers to a liquid level switch that can measure and control liquid level under high temperature conditions.

High temperature float switches provide consistent and reliable switching points in high temperature and other extreme applications. These sensors are made of durable stainless steel floats that slide on stainless steel stems.

As the float moves over the heat-resistant internal switch, its built-in magnetic field activates the reliable switch.

The high temperature level switch can be mounted on the top of the tank, on the side of the tank, or from the bottom of the tank.

There is also a tuning fork level switch. Features of compact tuning fork level switch:

The temperature can reach 150 ℃, and it is used for general liquid level measurement at higher temperature.

Extended Reading: Case: High Temperature Radar Level Transmitter for Melted Salt-Solar Photovoltaic Power Station

Float Type Level Switches

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
SI-U05 Cable Float Level Sensor & Swtich

Continuous Level Sensor Series

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.

Frequently
Asked
Questions

Common liquid level sensors are:
Float type liquid level sensor, magnetostrictive liquid level sensor,
Capacitive liquid level sensor, resistance liquid level sensor,
Radar level sensor, laser level sensor,
Ultrasonic liquid level sensor, pressure sensor,
Bubble level sensor, isotope level sensor,
Thermodynamic liquid level sensor
Therhere are 7 main types of level transmitters that Sino-Instroffers. Each type of transmitter works in a different way, and makes it useful for different types of processes.
More about level sensors from Wikipedia.

The liquid level sensor is a pressure sensor that measures liquid level. The static pressure input type liquid level transmitter is based on the principle that the measured liquid static pressure is proportional to the height of the liquid. It uses an isolated diffused silicon sensor or a ceramic capacitive pressure sensitive sensor to convert the static pressure into an electrical signal. Temperature compensation and linear correction are converted into standard electrical signals (usually 4~20mA/1~5VDC)

Float level sensor: Float level sensor is designed and produced based on the principle of buoyancy and static magnetic field. The position of a floating ball with a magnet (floating ball for short) in the measured medium is affected by buoyancy. The change of the liquid level causes the position of the magnetic float to change. The role of the magnet and sensor (reed switch) in the floating ball changes the number of components (such as fixed resistance) connected in series to the circuit. Thereby changing the electrical quantity of the instrument circuit system. That is, changes in the position of the magnetic float cause changes in the electrical quantity. The change of the electrical quantity is detected to reflect the liquid level in the container.

Sino-Inst offers over 10 Guided Wave Radar level transmitters for level measurement. About 50% of these are Radar level meters, 40% is the tank level sensor.

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

Sino-Inst is a globally recognized supplier and manufacturer of Guided Wave radar level measurement instrumentation, located in China.

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Positive Displacement Flow meter Technology

What is a Positive Displacement Flow meter?

Positive displacement flow meters are referred to as PD flow meters or PDF. They are the most accurate type in flow meters. Volumetric flow measurement uses a fixed small volume to repeatedly measure the volume of fluid passing through the flowmeter. It uses mechanical measuring elements to continuously divide the fluid into a single known volume part. The total flow volume is measured according to the number of times that the metering chamber is filled and discharged with the volume part of the fluid successively and repeatedly.

Positive Displacement Flow Meter Working Principle

In principle, PDF is a hydraulic engine that absorbs a small amount of energy from the fluid. This energy is used to overcome the frictional force of the flow detection element and the rotation of the accessories. At the same time, a pressure drop is formed at the inflow and outflow ends of the meter.

The working principle of a typical PDF (gear type) is shown in Figure 1.

The two shank round gears have a special shape that rolls to each other and rotates in contact.
P1 and p2 represent the inlet pressure and the outlet pressure respectively, obviously p1>p2.

Figure 1(a) The lower gear is under the action of the two pressure differences. Produce counterclockwise rotation, which is the driving wheel;
The upper gear has equal pressure on both sides. It does not produce a large rotating moment and is a driven wheel. Driven by the lower gear, it rotates clockwise.

In the position of Figure 1(b), both gears generate a rotational torque under the action of differential pressure and continue to rotate.

When rotating to the position in Figure 1(c), the upper gear becomes the driving wheel. The lower gear becomes the driven wheel. Continue to rotate to the same position as Figure 1(a) to complete a cycle.

One cycle action discharges the fluid volume of the four crescent-shaped cavities enclosed by the gear and the shell wall. This volume is called the “circulation volume” of the flow meter.

Suppose the circulation volume of the flow meter is u, and the number of gear rotations in a certain period of time is N. Then the volume of fluid flowing through the flowmeter during this time is V,

Then V=Nu(1)

The rotation of the Nanyuan gear is transmitted to the counter through the magnetic seal coupling and the transmission reduction mechanism to directly indicate the total amount flowing through the flowmeter.

If the sending device is attached and then equipped with an electric display instrument, it can realize that the remote transmission is only the instantaneous flow or the cumulative flow.

Although there are many segmentation methods to form various forms of PDF, most of them have similar basic characteristics.

The main reason for the PDF error is the leakage of the gap between the movable measuring piece and the static measuring chamber that divides a single fluid volume.

One of the reasons for leakage is to overcome the frictional resistance of moving parts. The second is the effect of pressure drop formed by the hydraulic resistance of the instrument.

Converter Tool: Volumetric Flow Rate & Pipe Diameter to Flow Speed Calculator

Positive displacement flow meter types Accuracy

PDF has high measurement accuracy, the basic error is generally ±1%R, and the special one can reach ±0.5%R or higher. Usually used in expensive media or where precise metering is required.

PDF has no effect on the metering accuracy when the flow velocity field of the rotating flow and the pipe blocker is distorted, and there is no requirement for the straight pipe section in front. This is of great significance in field use.

PDF can be used for the measurement of high viscosity fluids. The range is wide, generally 10:1 to 5:1, and special can reach 30:1 or more.

PDF is a direct-reading instrument that does not require external energy, and can directly obtain the cumulative total, which is clear and easy to operate.

Positive displacement flow meter types

There are many types of PDF, which can be classified according to different principles. According to the structure of the measuring element, there are the following types:
1) Rotor type
2) Scraper type
3) Rotating piston type
4) Membrane type, etc.

Read more about: Types of positive displacement flow meter

Positive displacement flow meter advantages and disadvantages

Advantages

PDF measurement accuracy is high, the basic error is generally ±0.5%R, and the special one can reach ±0.2%R or higher. Usually used inexpensive media or occasions requiring precise measurement.

PDF has no effect on the measurement accuracy when the flow velocity field of the rotating flow and the pipe choke is distorted, and there is no requirement for the front straight pipe section. This is of great significance in on-site use.

PDF can be used for the measurement of high-viscosity fluids.

The range is wide, generally 10:1 to 5:1, and special can reach 30:1 or more.

PDF is a direct-reading instrument without external energy. The cumulative total can be directly obtained, which is clear and easy to operate.

In the indirect mass flow measurement combined with volumetric flowmeters, PDF is compared with volumetric flowmeters derived from velocity equations. The volume is a direct geometrical quantity. The influencing factors of the volumetric quantity are simpler.

In the measurement of high-pressure natural gas that is not suitable for density meter measurement, the compression coefficient of difficult-to-handle gas can be obtained indirectly with PDF.

Disadvantages

The PDF structure is complex, bulky, and heavy, especially the larger-diameter PDF is bulky. Therefore, it is generally only suitable for small and medium-sized.

Compared with several other types of general flow meters (such as differential pressure, float, electromagnetic). PDF’s measured medium types, medium working conditions (temperature, pressure), and caliber limitations are larger, and the scope of application is narrow.

Due to the thermal expansion and deformation of parts at high temperatures, and the brittleness of materials at low temperatures, PDF is generally not suitable for high and low temperature applications. At present, the usable temperature range is roughly -30~+160℃, and the maximum pressure is 10MPa.

Most PDF instruments are only suitable for clean single-phase fluids. When particles and dirt are contained, a filter must be installed upstream, which will increase the pressure loss and increase maintenance work. For measuring liquids containing gas, a gas separator must be installed.

PDF security is poor. If the detection moving parts are stuck, the fluid cannot pass through, and the cut-off piping system cannot be used. However, some structural designs (such as Instromet’s waist wheel flowmeter) have a built-in bypass in the housing. When the detection moving element is stuck, the fluid can pass through the bypass.

Read more about Mass Flow Rate vs Volumetric Flow Rate

Use and Maintenance

  1. The volumetric flowmeter should be installed and used in accordance with the standard flow range, nominal pressure and flow direction marks on the nameplate.
  2. The positive displacement flowmeter should work under the condition that the fluid temperature is -20~+120℃ and the ambient temperature is -20~+55℃ and the relative humidity of the environment is not more than 80%.
  3. When the positive displacement flowmeter leaves the factory, it is calibrated with water at room temperature. If the measured fluid is different from the water at room temperature,the constant should be corrected or re-calibrated with the actual measured fluid, but for fluids with a viscosity less than 5×10-6m2/s (5Mpa.s), there is no need to re-calibrate.
  4. Under normal circumstances, the service life of positive displacement flowmeters is generally from six months to one year, depending on the severity of the working conditions. And should be removed and washed regularly. If the shaft or bearing is found to be severely worn, it should be replaced and re-calibrated.

Extended reading: Cylinder Gear flow meter for micro flow measurement.

The Sanitary Positive Displacement Flow Meter is made of stainless steel and is quickly connected by Tri-clamp. Can be used to measure viscous liquids in the food industry. Such as sweeteners, edible oil, palm oil, honey, fat, tallow, fat, syrup, molasses, etc.

Gas Roots flowmeter is an instrument that accurately measures gas flow, based on the principle of volumetric measurement. For accurate metering of gas flow through closed pipes.

The flowmeter is composed of two parts: Roots flow sensor and display instrument. It can be used to measure non-corrosive gases such as natural gas, city gas, propane, nitrogen, and industrial inert gases. Mainly used in gas business settlement in catering, hotel and other industries. Gas metering for transmission and distribution network, gas pressure regulating station metering, industrial and civil boilers and other gas metering. Can also be used as a standard flow meter.

Rotary positive displacement gas flow meter is mainly composed of flow meter body, rotating element, electronic display device or mechanical display device.

There is a metering chamber within the housing of the flowmeter. There are one or two pairs of rotating elements that can rotate tangentially.

A pair of drive gears are mounted coaxially with the two rotating elements outside the flowmeter housing. They mesh with each other. Thereby, the mutual linkage of the two rotating elements is realized.

For each revolution, a fixed amount of gas is expelled.

The number of revolutions of the rotating element is recorded, based on the volume of the metering chamber space (cycle volume). The volume of gas flowing through the flowmeter can be obtained.

Positive displacement flow meter vs turbine

A turbine flowmeter has the characteristics of simple structure, lightweight, simple maintenance, and adaptability to high parameters (high temperature, high pressure, and low temperature). Turbine flowmeters are currently mainly used in the measurement of natural gas, coal gas, petroleum, organic liquids, inorganic liquids, cryogenic fluids, liquefied gas, and other media.

So is the turbine flowmeter a positive displacement flowmeter?

A turbine flowmeter is not a positive displacement flowmeter, but a velocity flowmeter. Turbine flow meters, positive displacement flow meters and Coriolis mass flow meters are three types of flow meters with excellent repeatability and accuracy.

Read more about Turbine Flow Meters

You may like:

Extended reading: Integral DP Flow Meter|Gas, liquid, steam|Compact structure

Sino-Inst, Manufacturer for Positive Displacement Flow Meters. For example crude oil flow meter, diesel flow meter, gasoline flow meter.

Sino-Inst’s Positive Displacement Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

Ultrasonic Liquid Level Measurement

The ultrasonic liquid level sensor is a non-contact measuring device. That can send and receive high-frequency sound waves to measure the distance to the surface of liquid-based materials.

The ultrasonic liquid level measurement uses the non-contact principle. It is most suitable for level measurement of hot, corrosive, and boiling liquids. It is used to measure liquid levels. Ultrasonic equipment that converts it into electrical signals to send to other instruments.

Sino-Inst offers a variety of ultrasonic liquid level sensors and transmitters for continuous, non-contact tank level measurement. If you have any questions, please contact our sales engineers.

Featured Ultrasonic Level Sensors

Extended reading: Guide to Ultrasonic Level Transmitters

The liquid level sensor is a pressure sensor that measures liquid level. The static pressure input type liquid level transmitter is based on the principle that the measured liquid static pressure is proportional to the height of the liquid. It uses an isolated diffused silicon sensor or a ceramic capacitive pressure sensitive sensor to convert the static pressure into an electrical signal. Temperature compensation and linear correction are converted into standard electrical signals (usually 4~20mA/1~5VDC)

Read more about: Differences! Static pressure vs dynamic pressure vs total pressure

The working principle of the ultrasonic level gauge: The high-frequency pulse sound wave emitted by the ultrasonic transducer is reflected on the surface of the measured level, and 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 sound wave transmission distance S and sound speed C and sound transmission time T can be expressed by the formula: S=C×T/2.

According to the characteristics of ultrasound, it is actually more suitable for occasions where the accuracy requirements are not high and the working environment is not harsh.

  1. Water treatment industry.

Water treatment industry, including sewage treatment, tap water, pure water manufacturing and other occasions.

The measured medium is basically sewage and clean water, which does not require high measurement accuracy. And the working environment is basically not corrosive, there is no electromagnetic interference, and most of them work in the open air. At most, large waves are encountered where the water enters, or there is a small amount of foam on the water surface.

More about Application 3: Level Measurement In Waste Water Treatment Plants.

  1. Water conservancy and hydrology Water conservancy and hydrology industry.

In the early years, it was mainly used to measure water level changes at the gate. In recent years, because the state has increased its investment in the water conservancy industry. Flash flood warnings and water level and rainfall monitoring must be carried out in small and medium river basins.

These occasions basically need 24VDC power supply and RS485 output.

Because they are all measured on the water surface, there is no requirement for the launch angle of the ultrasonic level gauge. There will be no volatility and foam influence.

  1. Farmland Irrigation With the scarcity of water resources, farmland irrigation has begun to implement water level and flow monitoring.

It is generally carried out on a relatively wide channel. Small channels generally do not need to be measured.

The common channel width is more than 1 meter.

4. Chemical companies mainly need anti-corrosion and explosion-proof ultrasonic level gauges.

Liquids in chemical companies are measured by ultrasonic waves, which are basically in storage tanks.

For example: sulfuric acid, hydrochloric acid, liquid caustic soda, toluene, xylene, olefin, ammonia, acetone, etc. These occasions can be solved with an ultrasonic level gauge. If it is in the reactor, it will be affected by stirring.

Extended Reading: GWR Level Sensor for High Temperature & High Pressure

Advantages of ultrasonic level sensor:

  1. Simple structure. Convenient reading. Convenient installation and maintenance.
  2. Safe and clean. Long life. High precision. Stable and reliable.
  3. Non-contact measurement. It is less affected by the viscosity and density of the liquid.

Disadvantages of ultrasonic level sensor:

  1. There should be no obstacles under the sound wave. Because the ultrasonic level sensor uses the principle of sound wave reflection to achieve liquid level measurement. If there are obstacles, it will affect the ultrasonic emission. It will cause signal loss and affect the measurement effect.
  2. The measurement of ultrasonic level sensor is prone to blind spots. This is because in the ultrasonic pulse transmission process. Because the mechanical inertia occupies the transmission time. Therefore, the small area near the ultrasonic transducer cannot receive the sound wave. The area that cannot be measured is called the blind zone. The size of the blind zone is related to the ultrasonic measurement distance. The smaller the measuring distance, the smaller the blind zone. The larger the measuring distance, the larger the blind zone.
  3. The measurement of ultrasonic level sensor is easily affected by temperature. In actual measurement, changes in temperature will cause changes in the speed of sound. This will lead to errors in the measurement.
  4. It is not suitable to measure pressure vessels. Because the pressure mainly affects the probe. And there is a certain relationship between pressure and temperature. Pressure changes will affect the temperature changes, which in turn affects the speed of sound. The accuracy of the measurement is affected.

Extended Reading: Procurement Guide for Ultrasonic liquid level sensors

Extended reading: What is the difference between ultrasonic and radar level transmitters?

Radar Level Transmitter is an application of microwave (radar) positioning technology in level measuring instruments. It transmits energy waves through a device that can emit energy waves (usually pulse signals). The energy waves are reflected when they encounter obstacles, and the reflected signals are received by a receiving device.

Extended Reading: Silo/Bin material level measurement system

According to the time difference of the energy wave movement process, the level change can be determined. The microwave signal is processed by the electronic device. Finally, the microwave signal is converted into an electrical signal related to the level.

Extended reading: Liquid mass flow controller

Liquid Level Measurement Using Ultrasonic Method

The basic principle of ultrasonic measurement of liquid level is: the ultrasonic pulse signal sent by the ultrasonic probe propagates in the gas, and is reflected after encountering the interface of air and liquid. After receiving the echo signal, calculate the propagation time of the ultrasonic wave. Convert the distance or liquid level height.

Read more: Guide: Non-contact Ultrasonic Level Sensing transmitters

Common Applications for Ultrasonic Liquid Level Sensors

Ultrasonic liquid level sensor integrates three functions of non-contact switch, controller and transmitter. Suitable for small storage tanks. In integrated systems or replace float switches, conductivity switches and static pressure sensors. It is also suitable for integrated applications in fluid control and chemical supply systems. for machinery, brakes and other equipment The application of small storage tanks is also a good choice.

Extended reading: The Secret of Ultrasonic Level Measurement

Ultrasonic Liquid Level Measurement

Extended Reading: How to Measure Volume of Liquid

The Ultrasonic Liquid Level Measurement Also Has the Following Characteristics:

  • The range of the ultrasonic liquid level sensor is 1.25 meters
  • Ultrasonic liquid level sensor DL10 output 4~20mA
  • Ultrasonic liquid level sensor DX10 outputs 0-5V voltage signal
  • Ultrasonic liquid level sensor probe material PVDF, resistant to acid and alkali corrosion
  • Narrow beam angle of 0 degrees, support static tube technologyWebCal software calibration, protection grade IP67

Extended reading: GWR Corrosive Liquid Chemical Level Sensor

Extended reading: Non-Contact Level Measurement

Sino-Inst offers over 10 Ultrasonic 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.

Request a Quote

Please enable JavaScript in your browser to submit the form