Non-contact radar level sensor

Radar level sensors are used for continuous non-contact level measurement of liquids or solids. And convert it into electrical signals. The radar level sensor emits high-frequency radio frequency pulses from its antenna. The pulse passes through the air gap. Reflects on a liquid or solid surface and returns to the antenna. The radar level sensor determines the flight pulse time and converts it to level height or distance. It can provide reliable liquid level measurement in difficult tanks with foam, steam, temperature or pressure, or liquid storage tank applications. Or dusty silos, silos, stockpiles, crushers, or transfer station applications. It contains 3-30 meters of grains, granules, powder, or aggregates.

List of Radar Level Sensors

List of Radar Level Sensors

Radar Level Transmitters – 120GHz

SeriesSI-FMF11 FMCW Radar Level Transmitter 120GHz
SI-FMF11
SI-FMF12 Frequency Modulated Continuous Wave Radar Level Sensor
SI-FMF12
SI-FMF13 FMCW Radar Water Level Sensor
SI-FMF13
SI-FMF15 FMCW Radar High Temperature Level Sensor
SI-FMF15
SI-FMF21 FMCW Radar Silo Level Sensor
SI-FMF21
Applicable medium:LiquidLiquid Liquid Liquid Solid
Measuring range:0.05m~30m0.05m~35m0.1m~100m0.1m~35m0.3m~150m
Antenna:32mm lens antenna42mm lens antenna78mm lens antenna78mm lens antenna78mm lens antenna + purging (or without purging)
Accuracy:±2mm±2mm±2mm (range below 35m)
±5mm (range between 35m-100m)
±2mm±5mm
Medium temperature:-40~80℃-40~110℃-40~110℃-40~200℃-40~110℃
Medium pressure:-0.1~0.3 MPa-0.1~1.6MPa-0.1~0.3MPa-0.1~2.5MPa-0.1~0.3MPa
Signal output:Two-wire system/4…20mA/HART protocol
Four-wire system 4…20mA/ RS485 Modbus
Two-wire system/4…20mA/HART protocol
Four-wire system 4…20mA/ RS485 Modbus
Two-wire system/4…20mA/HART protocol
Four-wire system 4…20mA/ RS485 Modbus
Two-wire system/4…20mA/HART protocol
Four-wire system 4…20mA/ RS485 Modbus
Two-wire system/4…20mA/HART protocol
Four-wire system 4…20mA/ RS485 Modbus
Power supply:Two-wire system/DC24V
Four-wire system/DC12~24V
Four-wire system/AC220V
Two-wire system/DC24V
Four-wire system/DC12~24V
Four-wire system/AC220V
Two-wire system/DC24V
Four-wire system/DC12~24V
Four-wire system/AC220V
Two-wire system/DC24V
Four-wire system/DC12~24V
Four-wire system/AC220V
Two-wire system/DC24V
Four-wire system/DC12~24V
Four-wire system/AC220V
Shell:Aluminum/plastic/stainless steelAluminum/plastic/stainless steelAluminum/plastic/stainless steelAluminum /Plastic /Stainless steelAluminum/plastic/stainless steel
Process connection:G1½A / 1½NPT thread / flange ≥DN50G2A thread/flange≥DN65Flange ≥DN80Flange ≥DN80Flange ≥DN80

Radar Level Transmitters – 80 GHz

SeriesLM78x0LM78x1LM78x2
Applicable medium:For normal solid applicationFor liquid applicationFor large range solid application
Measuring range:0.3 m ~ 60m0.08m~30m0.6m ~ 120m
Antenna:Lens antenna/
anti-corrosive antenna /
flange isolated by quartz
Lens antenna/
anti-corrosive antenna /
flange isolated by quartz
Lens antenna/
anti-corrosive antenna /
flange isolated by quartz
Accuracy:±1mm±1mm±1mm
Medium temperature:T0:-40~85℃;
T1:-40~200℃;
T2:-40~500℃;
T3:-40~1000℃
T0:-40~85℃;
T1:-40~200℃;
T2:-40~500℃;
T3:-40~1000℃
T0:-40~85℃;
T1:-40~200℃;
T2:-40~500℃;
T3:-40~1000℃
Medium pressure:-0.1~2MPa-0.1~2MPa-0.1~2MPa
Signal output:4 ~ 20mA or RS-4854 ~ 20mA or RS-4854 ~ 20mA or RS-485
Power supply:15~28VDC15~28VDC15~28VDC
Shell:Aluminum alloy, stainless steelAluminum alloy, stainless steelAluminum alloy, stainless steel
Process connection:Thread or flangeThread or flangeThread or flange

Radar Level Transmitters – 26 GHz

SeriesSIRD-901 SIRD-902 SIRD-902T SIRD-903 SIRD-904 SIRD-905 SIRD-906 SIRD-908 SIRD-909
Applicable medium:All kinds of corrosive liquidSlightly corrosive liquidCorrosive liquids, vapors, volatile liquidsSolid material, Strong dust
easy to crystallize, condensation occasion
Solid material, Strong dust,
easy to crystallize, condensation occasion
Solid particles, PowderHygienic liquid storage,
Corrosive container
Rivers, Lakes, ShoalRivers, Lakes, Shoal
Measuring range:
10 meters
30 meters20 meters70 meters80 meters30 meters20 meters30 meters70 meters
Antenna:Sealing horn / PTEEHorn Antenna Φ46mm/ Horn Antenna Φ76mm /Horn Antenna Φ96mm / Special CustomInternal tapered rod antenna PVDF / 78mm
Internal tapered rod antenna PFA / 78mm
Horn Antenna Φ76mm / Φ96mm / Φ121mm/Special CustomParabolic antenna Φ196mm /Φ242mmHorn Antenna Φ76mm / Φ96mm / Φ121mm/Special CustomViton / (-40~130) ℃Horn antenna with 76mm/ 96mmHorn antenna with 76mm/ 96mm/ special custom
Accuracy:± 5mm± 3mm±3mm±15mm±15mm±15mm± 3mm± 3mm± 10mm
Medium temperature:-40℃~130℃-40℃~130℃(Standard type)
-40℃~250℃(High-temperature type)
-40℃~130℃(Standard type)
-40℃~250℃(High-temperature type)
-40℃~130℃(Standard type)
-40℃~250℃(High-temperature type)
-40℃~130℃(Standard type)
-40℃~250℃(High-temperature type)
-40℃~130℃(Standard type)
-40℃~250℃(High-temperature type)
-40℃ ~ 130℃-40℃ ~ 100℃40℃ ~ 100℃
Medium pressure:-0.1~0.3 MPa-0.1 ~ 4.0 MPa-0.1~2.0 MPa-0.1~4.0 MPa (Flat flange)
-0.1~0.3MPa (Universal flange)
-0.1 ~ 0.3 MPa-0.1 ~ 4.0 MPa (Flat flange)
-0.1 ~ 0.3 MPa (Universal Flange)
-0.1~4.0 MPaNormal-pressure Normal-pressure
Signal output:4… 20mA /HART (2-wire / 4-wire)
RS485/ Modbus
4… 20mA /HART(2-wire / 4-wire)
RS485/ Modbus
4… 20mA /HART(2-wire / 4-wire)
RS485/ Modbus
4… 20mA /HART (2-wire / 4-wire)
RS485/ Modbus
4… 20mA / HART (2-wire / 4-wire )
RS485/ Modbus
4… 20mA /HART (2-wire / 4-wire )
RS485/ Modbus
4… 20mA/HART (2-wire / 4-wire )
RS485/ Modbus
RS485 / Modbus ( 6~24V DC)
4~20mA / Hart Two-wire ( 24V DC)
RS485 / Modbus ( 6~24V DC)
4~20mA / Hart Two wire ( 24V DC)
Power supply:2-wire(DC24V)/ 4-wire(DC24V /AC220V)2-wire(DC24V)/ 4-wire(DC24V /AC220V)2-wire(DC24V)/ 4-wire(DC24V /AC220V )2-wire(DC24V)/ 4-wire(DC24V /AC220V)2-wire(DC24V)/ 4-wire(DC24V /AC220V)2-wire(DC24V)/ 4-wire(DC24V /AC220V)2-wire(DC24V)/ 4-wire(DC24V /AC220V)(6 – 24V) DC  / Four-wire
24V DC / Two wire
(6 – 24V) DC  / Four-wire
24V DC / Two wire
Shell:Aluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic /Single chamberAluminum / Plastic / Single chamber
Process connection:Thread, Flange Thread, Flange FlangeUniversal FlangeThread, Universal FlangeThread, FlangeFlange Thread G1½ A″ /Frame /Flange Thread G1½ A″ /Frame /Flange

Radar Level Sensors – 6 GHz

Series
SIRD-801
SIRD-802SIRD-803SIRD-804 SIRD-805 SIRD-806
Applicable medium:Liquid, slightly corrosive liquidLiquid, especially for corrosive liquidLiquid, especially with pressure and Volatile LiquidSolid particles or block material,
And it is not suitable for solid powder
Liquid, especially suitable for low dielectric constant, sticky, with mixing liquidSolid, especially suitable for high temperature conditions
Measuring range:20m20m35m35m20m15m
Antenna:The Rod Antenna ( PP/PTFE )The Rod Antenna (PTFE)The Horn AntennaThe Horn AntennaThe Horn AntennaThe Horn Antenna
Accuracy:±10mm± 10mm± 10mm± 20mm± 10mm± 20mm
Medium temperature:(-40 ~ 130) ℃-40℃~130℃(Standard type)
-40℃~180℃(High temperature type)
-40℃~130℃(Standard type)
-40℃~250℃(High temperature type)
-40℃~130℃(Standard type)
-40℃~250℃(High temperature type)
-40℃~130℃(Standard type)
-40℃~250℃(High temperature type)
(-40 ~ 400) ℃
Medium pressure:(-0.1 ~ 0.3) MPa(-0.1 ~ 1.6) MPa(-0.1 ~ 4) MPa(-0.1 ~ 0.3) MPa(-0.1 ~ 4) MPa(-0.1 ~ 0.3) MPa
Signal output:(4 ~ 20) mA/HART(4 ~ 20) mA/HART(4 ~ 20) mA/HART(4 ~ 20) mA/HART(4 ~ 20) mA/HART(4 ~ 20) mA/HART
Power supply:Two-wire (DC24V)
Four-wire(DC24V / AC220V)
Two-wire (DC24V)
Four-wire(DC24V/AC220V)
Two-wire (DC24V)
Four-wire(DC24V/AC220V)
Two-wire (DC24V)
Four-wire(DC24V/AC220V)
Two-wire (DC24V)
Four-wire(DC24V/AC220V)
Two-wire (DC24V)
Four-wire(DC24V/AC220V)
Shell: Aluminum /Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steelAluminum / Plastic / Stainless steel
Process connection:Flange (optional) / ThreadWith PTFE plate flangeFlange (optional) / ThreadUniversal joint flangeFlangeFlange

Radar Level Sensor Advantages and Disadvantages

Advantages of radar level measurement

  • Measurement is not affected by temperature, pressure, or dust
  • User-friendly adjustment saves time
  • Non-contact, continuous level measurement over larger ranges
  • Unaffected by sludge and biomass, dust, foam, oil, grease and other coatings, uneven surfaces, turbulence, pressure, and vacuum
  • Single-frequency radar level sensors for liquid sensing, dual-frequency radar level sensors for level measurement of aggregates, gravel, sand, coal, asphalt, and other solids
  • Simple mounting and push-button calibration

Disadvantages of radar level measurement

radar level measurement manufacturer
  • Very sensitive to build-up on the sensor surface.
  • They are very expensive. Price increases with accuracy.

Extended reading: Amazing Solutions for Continuous Liquid Level Measurement

Radar Level Sensor Working Principle

Radar Level Measurement and guide wave radar level measurement
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.

Radar Level Sensor Application

From the shape of the tank, Radar Level Sensor can measure the liquid level of spherical tanks, horizontal tanks, cylindrical tanks and cylindrical cone tanks.
As far as storage tank functions are concerned, Radar Level Sensor can measure the liquid level in storage tanks, buffer tanks, microwave tubes and bypass tubes.
From the measured medium, Radar Level Sensor can measure liquids, particles, slurries, etc.

Radar Level Sensor for Solids

Radar Level Sensor is widely used in the measurement of solid material levels in the industry. It has a good measurement effect for the working conditions of extreme dust and various interference factors that affect the measurement in the silo.

  • Material storage level detection in the mining industry. Level detection of silos such as coarse broken silos, fine broken silos and fine ore silos.
  • Storage level detection of materials in the coal industry. Including the level detection of raw coal silos, clean coal silos and other silos.
  • Material storage level detection in the cement industry. Including clinker warehouse, raw meal homogenization warehouse, raw material mixing warehouse, limestone storage warehouse, raw coal warehouse, cement mixing warehouse and other silo level detection.
  • Storage level detection of materials in the power industry. Such as the detection of raw coal silos, pulverized coal silos and dry ash silos in thermal power plants.

Radar Water Level Sensor

Radar Level Sensor is a level detection instrument using microwave technology.

Radar Water Level Sensor

It is mainly suitable for detecting the water level of natural waters such as rivers and lakes. It can also be used to detect the water level of large-scale reservoirs, reservoirs, sewers, and other open-air channels.

As a detection terminal, this product can effectively assist in monitoring water level changes and provide accurate water level information for monitoring units.

The product adopts the pulse radar detection method. It can work stably around the clock. The measurement result is accurate and reliable.

The non-contact detection method makes it more widely used. It can even be used in complex water environments with organic pollutants or sediments.

Ultrasonic vs Radar Level Sensor

What is the difference between Ultrasonic Level Sensor and Radar Level Sensor?

Ultrasonic Level Sensor and Radar Level Sensor are non-contact liquid level measuring instruments. As the name suggests, one uses ultrasonic waves and the other uses electromagnetic waves. In addition, what are the differences between ultrasonic level sensors and radar level sensors?

Ultrasonic Level Sensor

Ultrasonic Level Sensor is a digital level meter controlled by a microprocessor. In the measurement, the pulsed ultrasonic wave is emitted by the sensor (transducer). The sound waves are received by the same sensor after being reflected by the surface of the object and converted into electrical signals.

The distance between the sensor and the object to be measured is calculated from the time between the emission and reception of the sound wave.
Because of the non-contact measurement. The measured medium is almost unlimited. It can be widely used to measure the height of various liquid and solid materials.

Radar Level Sensor

Radar Level Sensor adopts the circuit design of a high-frequency microstrip line structure. The internal circuit generates microwave pulse signals.

Based on the design principle of the high-frequency waveguide, the microwave pulse is emitted from the end of the antenna through the PTFE emitter.

When the transmitted pulse hits the surface of the measured medium. Part of the energy is reflected back and received by the same antenna.

Through the principle of time extension technology, the time interval between the transmitted pulse and the received pulse is calculated. So as to further calculate the distance from the antenna to the surface of the measured medium.

Simply put:

  1. The relative price of Radar Level Sensor is relatively high;
  2. Radar Level Sensor has higher accuracy than ultrasonic;
  3. The measuring range of radar is larger than that of ultrasonic;
  4. When using Radar Level Sensor, consider the dielectric constant of the medium.
  5. Radar Level Sensor has horn type, rod type and cable type. Compared with ultrasonic, it can be applied to more complicated working conditions;
  6. Ultrasonic cannot be applied to working conditions such as vacuum, high steam content or foam on the liquid surface.

Extended reading: The Secret of Ultrasonic Level Measurement

Radar Level Transmitter Calibration

How do you calibrate the radar level transmitter?

Set up the guided wave radar level transmitter

HART communicator, power supply, and the multimeter are as below (see below calibration setup Diagram).

Check the configuration of the lower range value (0% level, 4 mA) and high range value (100% level, 20 mA).
Make sure that the inputted data is as per the datasheet.
For example, the lower range value is 10 inch and the high range value is 35 inches (both of it are measured from the bottom of the level transmitter probe)

Fill the level transmitter chamber with water up to the 0% level.
Read the level measurement in the transmitter LCD (or in the HART communicator). Set this condition as 0% level through the HART communicator.

Read the mA output of the transmitter by using a multimeter.
Adjust (if any) through the HART communicator so that the output of the transmitter (on the multimeter) is 4 mA.

Fill the level transmitter chamber with water up to 100% level.
Read the level measurement in the transmitter LCD (or in the HART communicator). Set this condition as 100% level through the HART communicator.

Read the mA output of the transmitter by using a multimeter.
Adjust (if any) through the HART communicator so that the output of the transmitter (on the multimeter) is 20 mA.

Frequently
Asked
Questions

Help Center

Radar level instruments measure the distance from the transmitter (located at some high point) to the surface of a process material located farther below in much the same way as ultrasonic transmitters – by measuring the time-of-flight of a traveling wave.

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 a 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 (GWR) level transmitter working principle

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

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

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

Request a Quote