807 Low Temperature Liquid Level Sensor is a customized product specially designed for liquid level measurement in low temperature environments such as liquid nitrogen, LNG, and liquid ammonia. -196℃~80℃ available.
This product has no moving parts and is not disturbed by the external environment. It has the advantages of stable and reliable long-term operation, high sensitivity, good linearity, low temperature resistance and corrosion resistance. The cryogenic level meter provides a variety of output signals RS232\ RS485\ 0～5V \4～20mA.
The connection position is equipped with integrated 4-bit terminal, defined as shown in Figure:
OUT +: Power Supply + OUT-: Power Supply- TEST +: Debug the interface TEST-: Debug the interface Note: The sensor TEST (R485) for 4 ~ 20 mA signal is for commissioning only
Precautions for use
There can only be one type of RS232/RS485/0-5V/4~20mA signal, and you can choose to use any one of them. The RS485 bus can connect multiple sensors at the same time, but the communication address of each sensor must be set in advance. The communication address of each sensor must be unique to prevent the bus from locking up. The RS485 bus uses a half-duplex chip, so the module should be allowed time to respond when reading data. The reading speed cannot be too fast. The time interval between two instructions during continuous reading cannot be less than 200ms.
It is recommended that the sensor be connected with a shielded wire, especially for RS232 communication. The communication wire should not be too long.
For RS232/RS485 signal sensors, when troubleshooting communication failure, you can swap the blue and yellow wires for testing. If the communication is successful, it means there is a wiring error. This operation is for digital communications only.
The power supply voltage of the sensor shall not exceed its normal working voltage, and the power consumption of the sensor power supply shall not be less than the power consumption of the sensor during normal operation.
The actual environment should meet the basic parameter requirements of the sensor and must not exceed the normal range, otherwise it will cause damage to the sensor and even cause other accidents.
The sensor outputs the position height signal of the medium. When the filtering is zero, the output value reflects the actual change of the liquid level. The output value changes with the rise or fall of the liquid level. After adding the filtering, the value will Becomes stable and lagging, the larger the filter value, the higher the temperature, the liquid level value will lag behind the change of the actual liquid level. Therefore, customers adjust the filter value based on device usage.
Please do not disassemble or damage the sensor maliciously, otherwise the warranty will be void.
All accessories such as rubber pads and O-rings of the sensor are not covered by the warranty.
More Low Temperature Liquid Flow and Pressure Measurement
807 Low Temperature Liquid Level Sensor is a customized sensor, which is limited to the measurement of low-temperature liquid level and cannot be used for other media.
We, Sino-Inst, are a professional high-tech enterprise focusing on the research and development, production, sales and engineering services of liquid level/pressure/flow sensors and transmitters, intelligent instruments and automated control systems. Our main products include liquid level, pressure and flow sensors, transmitters and other field measurement instruments.
We provide customers with measurements under various high temperature, low temperature, explosion-proof and other special working conditions. If you need Low Temperature Liquid Level measurement, please feel free to contact our sales engineers.
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Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
The Cryogenic Level Sensor is a capacitance-based level transmitter for cryogenic liquid level measurement. Cryogenic Level Sensor is a customized product for liquid level measurement in low temperature environments such as liquid nitrogen, LNG, and liquid ammonia. Also called liquid nitrogen level sensor. This product has no moving parts and is not disturbed by the external environment. It has the advantages of long-term operation, high sensitivity, good linearity, low temperature resistance, etc. The cryogenic level sensor provides a variety of output signals. It is used in LNG liquid natural gas, petroleum, chemical industry, metallurgy, electric power, papermaking, pharmaceutical and other fields.
The intelligent control system of liquid nitrogen tank is based on ultra-low temperature application technology. It adopts the design method from qualitative to quantitative. It integrates the integrated application system of liquid nitrogen monitoring, equipment control, data communication, computer and alarm.
The liquid nitrogen tank intelligent control system uses technological means such as networking, communication, database, cloud storage, etc. to provide users with intelligent solutions that serve the entire life cycle of liquid nitrogen tank control.
Extended Reading:
Laser Level Transmitter is a large-range, high-accuracy explosion-proof level measurement product supplied by Sino-Inst.
The liquid nitrogen tank automatic liquid supply system solution can realize the control, monitoring, monitoring and fault diagnosis of all aspects of the entire liquid nitrogen supply system. Meet the requirements of liquid nitrogen tank intelligent control system for liquid supply system in various fields. Including liquid nitrogen residual monitoring, centralized liquid supply, separate liquid supply, fault diagnosis and alarm and system information integration and other requirements.
The system has powerful monitoring functions, data calculation and analysis and diagnosis capabilities. It can realize mutual communication control between various devices.
As shown in the figure, the purpose of measuring the liquid level of low temperature medium is achieved by measuring the gas pressure in the pressure guiding pipe.
Because the liquid in the high-pressure side pressure guiding pipe is in a normal temperature state above the boiling point.
Therefore, the liquid in the pressure guiding tube evaporates into gas until saturated gas is formed in the pressure guiding tube.
The differential pressure transmitter should be installed above the maximum liquid level. The high pressure side is connected to the liquid phase pressure guiding pipe. Not only can the transmitter be in a working environment at room temperature, but also the low-temperature liquid can be fully vaporized.
In order to easily adjust the zero position of the instrument and replace the instrument, a balance valve should be installed between the high and low pressure sides of the differential pressure transmitter.
After the differential pressure transmitter is installed, the zero position should be adjusted, then the gas phase pressure pilot valve PL should be opened, and the zero position should be adjusted again under the working pressure.
Then open the liquid phase pressure pilot valve PH. Wait for a while for the cryogenic liquid to fully vaporize. Then close the balance valve to put the transmitter into operation.
When checking or adjusting zero during use, first open the balance valve to balance the pressure on the high and low pressure sides of the differential pressure transmitter, and then close the liquid phase pressure guide valve to check or adjust the zero position.
If the vaporized gas of the liquid to be tested is dangerous in contact with the air, certain safety measures should be taken during maintenance.
Principle: The principle of the connector. Developed according to the principle of buoyancy and magnetic coupling.
When the liquid level in the container under test rises and falls. The permanent magnet steel in the float is transmitted to the magnetic flip column indicating panel through magnetic coupling. Flip the red and white columns over 180°.
The column turns from white to red when the liquid level rises. The column turns from red to white when the liquid level drops.
The junction of red and white on the panel is the actual height of the liquid level in the container, so as to realize the liquid level display.
The structure of the float level meter is mainly designed and produced based on the principles of buoyancy and static magnetic field.
The position of the float with a magnet (abbreviated as float) in the measured medium is affected by buoyancy: changes in the liquid level lead to changes in the position of the magnetic float.
The magnet and sensor (reed switch) in the floating ball act to change the number of components (such as fixed-value resistors) connected in series to the circuit, thereby changing the electrical quantity of the instrument circuit system.
That is, the change of the position of the magnetic float causes the change of the electrical quantity.
The liquid level in the container is reflected by detecting the change of the electrical quantity.
It is designed and manufactured using the principle of mechanical balance.
When the liquid level changes, the original mechanical balance will reach a new balance through the movement of the steel belt under the disturbance of the buoyancy of the float.
The liquid level detection device (float) drives the steel belt to move according to the liquid level. The displacement transmission system drives the transmission pin to rotate through the movement of the steel belt. It then acts on the counter to display the liquid level.
The radar level meter is a measuring instrument based on the principle of time travel. The radar wave runs at the speed of light, and the running time can be converted into a level signal by electronic components.
The probe emits high-frequency pulses and propagates along the cable probe. When the pulses meet the surface of the material, they are reflected back and received by the receiver in the instrument. The distance signal is converted into a level signal.
When the sensor of the magnetostrictive level transmitter works, the circuit part of the sensor will excite a pulse current on the waveguide wire. When the current propagates along the waveguide wire, a pulse current magnetic field will be generated around the waveguide wire.
There is a float outside the sensor rod of the magnetostrictive liquid level gauge. This float can move up and down along the rod with the change of the liquid level.
Inside the float there is a set of permanent magnetic rings.
When the magnetic field of the pulse current meets the magnetic field of the magnetic ring generated by the float, the magnetic field around the float changes so that the waveguide wire made of magnetostrictive material generates a torsional wave pulse at the position of the float. The waveguide wire is returned and detected by the detection mechanism.
By measuring the time difference between the pulse current and the torsional wave, the position of the float, that is, the position of the liquid surface, can be accurately determined.
The radio frequency admittance level meter is composed of a sensor and a control instrument. The sensor can be installed on the roof of the warehouse using rod-type, coaxial or cable-type probes.
The pulse card in the sensor can convert the material level change into a pulse signal and send it to the control instrument. After the control instrument is processed and converted into engineering quantity and displayed, it realizes the continuous measurement of the material level.
The working principle of the tuning fork level controller is to make the tuning fork vibrate at a certain resonance frequency through a pair of piezoelectric crystals installed on the tuning fork base.
When the tuning fork is in contact with the measured medium, the frequency and amplitude of the tuning fork will change. These changes are detected, processed and converted into a switching signal by an intelligent circuit.
The glass plate type liquid level meter is connected to the container through the flange to form a communication device, and the height of the liquid level in the container can be directly read through the glass plate.
The pressure level transmitter adopts the principle of static pressure measurement.
When the liquid level transmitter is put into a certain depth in the measured liquid.
At the same time as the pressure on the liquid surface of the sensor, the pressure of the liquid is introduced into the positive pressure chamber of the sensor through the air-conducting stainless steel. Then the atmospheric pressure Po on the liquid surface is connected to the negative pressure chamber of the sensor to offset the Po on the back of the sensor.
The pressure measured by the sensor is: ρ .g.H , and the liquid level depth can be obtained by measuring the pressure P .
Capacitive level meters measure the level of liquid level by measuring changes in capacitance.
It is a metal rod inserted into the liquid container. The metal rod is used as one pole of the capacitor. The wall of the container is used as the other pole of the capacitor.
The medium between the two electrodes is the liquid and the gas above it.
Because the dielectric constant ε1 of the liquid and the dielectric constant ε2 on the liquid surface are different. For example: ε1>ε2.
Then when the liquid level rises, the total dielectric constant value between the two electrodes of the capacitive liquid level gauge increases accordingly and the capacitance increases.
Conversely, when the liquid level drops, the value of ε decreases, and the capacitance also decreases.
Therefore, the capacitive liquid level meter can measure the level of the liquid level through the change of the capacitance between the two electrodes.
The intelligent electric displacer liquid level meter is a liquid level measuring instrument designed according to Archimedes’ law and the principle of magnetic coupling. The instrument can be used to measure the liquid level, boundary level and density, and is responsible for the output of upper and lower limit alarm signals.
It is designed and manufactured using the principle of mechanical balance.
When the liquid level changes, the original mechanical balance will be disturbed by the buoyancy of the float. The new balance will be achieved by the movement of the steel belt (rope).
The liquid level detection device (float) drives the steel belt (rope) to move according to the liquid level. The displacement transmission system drives the on-site indicating device through the movement of the steel belt (rope), and then displays the liquid level on the display device.
The pontoon is submerged in the liquid in the pontoon chamber and is rigidly connected to the torsion tube system. The force on the torsion tube system is the net weight of the pontoon minus the buoyancy on the pontoon. Under the action of this combined force, the torsion tube is twisted by a certain angle.
Changes in the position, density or boundary level of the liquid in the buoyancy chamber cause the buoyancy force of the buoyancy immersed in the liquid to change, so that the twisting angle of the tube also changes.
This change is transmitted to a sensor rigidly connected to the torsion tube. Change the sensor output voltage. Then it is amplified by electronic components and converted into 4-20mA current output.
Displacer level transmitters use microcontrollers and associated electronics to measure process variables. Provides current output. Drive LCD display and provide HART communication capability.
The magnetic-sensitive electronic two-color liquid level meter is made of high-quality stainless steel and imported electronic components.
The display part adopts high-brightness LED two-color light-emitting tube to form a columnar display screen.
Through the red and green changes of the LED light column, the upper and lower limit alarm and control of the liquid level can be realized.
The external liquid level meter is an instrument that measures the liquid level from the outside of the container using the principle of sonar ranging and “micro-vibration analysis” technology.
Two small external level gauge ultrasonic sensors are installed on the bottom of the tank and the other on the side wall of the tank to compensate for density changes.
The signal of the external level meter sensor is converted by the microprocessor and output to the local display or user control system. Can calculate the height of the liquid in the tank and the volume of the liquid in the tank
The hydrostatic level transmitter encapsulates the diffused silicon oil-filled core in a stainless steel shell.
The front protective cap protects the sensor diaphragm. It can also make the liquid contact the diaphragm smoothly. The water wire is sealed with the housing. The ventilation tube is connected to the outside world in the cable. The internal structure is designed to prevent condensation.
Ultrasonic level Sensor is composed of a complete ultrasonic sensor and control circuit.
The ultrasonic wave emitted by the ultrasonic sensor is reflected by the liquid surface. The time required to return is used for calculation.
The temperature influence in the ultrasonic transmission process is corrected by the temperature sensor, which is converted into the distance between the liquid surface and the ultrasonic sensor.
Output 4mA-20mADC analog signal through LCD screen. Realize remote reading of field instruments.
The differential pressure liquid level transmitter is an electrical component that measures the high and low pressure difference, and then converts it into a current signal by the conversion component and transmits it to the control room.
Differential pressure liquid level transmitter is mainly used for liquid level measurement of closed pressure vessels.
The size of the differential pressure also represents the size of the liquid level height.
Use a differential pressure gauge to measure the differential pressure between the gas and liquid phases to know the liquid level.
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The general liquid nitrogen tank can have its own liquid level indicator. Some industrial liquid nitrogen storage tanks, without liquid level display, can be equipped with our very low temperature liquid nitrogen liquid level sensor. Local display is supported. At the same time, it supports signal output, which can be connected to the recorder or the user’s monitoring system.
The design temperature of the liquid nitrogen tank is -196°C. There are two kinds of conventional pressures designed, one is 0.8MPa and the other is 1.6MPa. These two design pressures are based on usage needs.
When nitrogen is under pressure, the temperature reaches -196°C. It will become a dark blue liquid, which is liquid nitrogen. Liquid nitrogen can be stored under pressure or without pressure.
Of course, users can also measure the pressure for liquid nitrogen storage tanks according to their own needs. Just use our Cryogenic Pressure Transducer.
If you want to divide the level sensor into two categories. Then it can be divided into contact type and non-contact type liquid level sensor according to the measurement of whether it is released from the medium.
There are 7 main types of level transmitters that Sino-Instrument offers. Each type of transmitter works in a different way, and makes it useful for different types of processes.
Sino-Inst is Manufacturer of Cryogenic Level Sensors for Liquid Nitrogen Tank Level Indicator. We supply more than 10 kinds of liquid nitrogen measure instruments.
Cryogenic Level Sensors are mainly used for level measurement of low temperature liquids. It can measure even liquids such as Liquid Nitrogen, Liquid Oxygen, etc.
Cryogenic Level Sensors enable stable level measurement. This greatly meets the measurement needs of many applications. Can be used from small to large tanks.
Sino-Inst’s Cryogenic Level Sensors, made in China, Having good Quality, With better price. Our level measurement instruments are widely used in China, India, Pakistan, the US, and other countries.
The entire team at Sino-Inst’s has received excellent training, so we can ensure that every client’s needs are met. For assistance with your product requirements, whether it’s a Cryogenic Level Sensor, flow sensor, or other device, give us a call.
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Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
A capacitive Level Sensor is also called an RF capacitance level meter. Capacitive Level Sensor is a liquid level (level) transmitter for liquid, oil, solid, and interface measurement.
Capacitive Level Sensors can be used for point level detection and continuous level measurement, particularly in liquids. The measuring principle is based on the change of the capacitance in a capacitor. The electrically conductive tank wall and a probe inside of the tank form a capacitor, The capacity changes of which are used to determine the level. This animation shows the measuring principle in conductive liquids and non-conductive liquids. The Capacitive Level Sensor can convert the changes of various levels and the height of the liquid level into standard current signals. Level Sensors can also support wireless transmission, RS485 digital communication transmission, etc.
The capacitive level sensor is based on the change of capacitance to perform liquid/level measurement. The level gauge electrode and the container form two electrodes of a capacitor. The capacitance value varies with the container.
The level of the material medium changes and changes, and is converted to the corresponding level output signal.
A basic requirement for measuring liquid/level with a capacitance level meter is the relative medium of the measured medium.
The electrical constant (the ratio of the dielectric constant of the measured medium to the air) should not change during the measurement.
Endress+Hauser has a good explanation video about Measuring Principle Capacitance. Let’s look together.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
RF Admittance Level Sensor is developed from radio frequency capacitance. More accurate and more applicable continuous level measurement.
RF Admittance Level Sensor is a continuous level measurement product designed based on the principle of radio frequency admittance. The product has the advantages of high stability, high sensitivity, and wide range of applications. Compared with the traditional capacitive level sensor, the RF Admittance Level Sensor adopts a modular design. The meaning of admittance is the reciprocal of the impedance in electricity. It is composed of resistive, capacitive and inductive components. The radio frequency is high Frequency radio spectrum. So radio frequency admittance can be understood as measuring admittance with high frequency radio waves. When the instrument is working, the sensor and the tank wall and the measured medium form an admittance value. When the height of the medium changes, the admittance value changes accordingly. The detection circuit converts the measured admittance value into a level signal output.
Sino-Inst offers a variety of Capacitance Level Transmitters for level measurement. If you have any questions, please contact our sales engineers.
Probe type: insulated flexible cable Process temperature: -100…200℃ Process pressure: -0.1…4.0MPa Output mode: 4～20mA Process connection: 3/4″BSPT threaded installation (standard)/flange installation (optional) Explosion-proof grade: ExiallCT4 (optional) Typical application: conductive liquid, interface, can be installed separately
RF Admittance Level Sensor-20-Flexible Cable
Probe type: flexible cable Process temperature: -50…140°C Process pressure: -0.1…1.6MPa Output mode: 4～20mA Process connection: 3/4″BSPT threaded installation (standard)/flange installation (optional) Explosion-proof grade: ExiallCT4 (optional) Typical application: deep well, super long range, can be installed separately
RF Admittance Level Sensor-21-Hard Rod Tube
Probe type: barrel type hard rod Process temperature: -100…200℃ Process pressure: -0.1…6.3MPa Output mode: 4～20mA Process connection: 1 1/2″BSPT threaded installation (standard)/flange installation (optional) Explosion-proof grade: ExiallCT4 (optional) Typical application: low dielectric constant liquid, can be installed separately
RF Admittance Level Sensor-22-Double insulated hard rod
Probe type: double rod insulated hard rod Process temperature: -100…260℃ Process pressure: -0.1…4.0MPa Output mode: 4～20mA Process connection: 3/4″BSPT threaded installation (standard)/flange installation (optional) Explosion-proof grade: ExiallCT4 (optional) Typical application: strong corrosive liquid with reference electrode, conductive liquid, interface, can be installed separately
RF Admittance Level Sensor-23-Insulated hard rod
Probe type: insulated hard rod Process temperature: -100…200℃ Process pressure: -0.1…6.3MPa Output mode: 4～20mA Process connection: 1″BSPT thread installation (standard)/flange installation (optional) Explosion-proof grade: ExiallCT4 (optional) Typical applications: interface, power off, strong stirring occasions, can be installed separately
RF Admittance Level Sensor-24-High temperature flexible cable
Probe type: insulated flexible cable Process temperature: -50…800 ℃ Process pressure: -0.1…4.0MPa Output mode: 4～20mA Process connection: 3/4″BSPT threaded installation (standard)/flange installation (optional) Explosion-proof grade: ExiallCT4 (optional) Typical application: high temperature insulating solid, can be installed separately
Specifications of RF Admittance Level Sensor
Power supply:
13VDC～35VDC
Output:
4～20mA
Environment temperature:
-40℃～70℃
Medium temperature:
-100℃～800℃
Linearity:
0.50%
Repeatability:
0.10%
Delay:
1～30s adjustable
Spark protection:
built-in spark protection circuit (to sensor)
Electrical interface:
M20*1.5
Cable:
The special connection cable between the split electronic unit and the sensor is standard 5m, the longest is 50m
Water and water treatment: reservoirs, sewage tanks, water treatment tanks, sedimentation tanks, digestion towers, gas pipelines, deep wells, drinking water networks, etc.
Cement: Stone silos, raw meal silos, cement silos, coal powder silos, slag storage silos, etc.
Metallurgy: ore silo, ore crusher, raw material silo, auxiliary silo, blast furnace, alumina powder silo, electrolytic cell buffer tank, etc.
Oilfield: crude oil or product oil storage tanks, three-phase separators, sedimentation tanks, sewage tanks (pools) and oil-water interfaces, drilling mud tanks, etc.
Papermaking: raw material warehouse, storage tower, drying drum, etc.
Others: quarry, food, pharmaceutical, environmental protection, shipbuilding and other industries
RF Admittance Level Sensor works based on radio frequency admittance level control technology. Radio frequency admittance level control technology is a development from capacitive level control technology. The material to which the sensor adheres is called hanging material. The anti-hanging material performance is better, the work is more reliable, and the measurement is more accurate. Level control technology with wider applicability. The meaning of “admittance” in “radio frequency admittance” is the reciprocal of impedance in electricity. It is composed of resistive, capacitive and perceptual components. “Radio frequency” means high frequency, so radio frequency admittance technology can be understood as a method of measuring admittance with high frequency current.
The important difference between point radio frequency admittance technology and capacitance technology is the use of three-terminal technology and the diversity of measurement parameters. The measurement signal at the center end of the circuit unit is connected with the center line of the coaxial cable. Then connect to the center end of the sensor.
At the same time, the shielding layer of the coaxial cable is suspended on a level that is very small and very stable, but has the same potential, the same phase and the same frequency as the measurement signal, but has no direct electrical relationship, that is, isolated from each other. The effect is equivalent to that the measured signal passes through a non-inverting amplifier with a gain of “1” and a strong drive capability. The output is connected to the shield of the coaxial cable. Then connect to the shielding layer of the sensor. The ground wire is another independent wire in the cable.
Because of the above-mentioned relationship between the center line of the coaxial cable and the outer shield, there is no potential difference between the two. Therefore, no current flows, that is, no current leaks from the center line. It is equivalent to no capacitance between the two or the capacitance is equal to zero. Therefore, the temperature effect of the cable and the installation of capacitors will not have an impact.
For the problem of hanging material on the sensor. Adopt a new sensor structure, five-layer concentric structure.
Sensor structure: The innermost layer is the center probe, the middle is the shielding layer, and the outermost is the grounded mounting thread, which is isolated by an insulating layer. As with the coaxial cable, there is no potential difference between the center probe and the shield. Even if the impedance of the hanging material on the sensor is small, no current will flow.
The electronic instrument measures only the current from the center of the sensor to the opposite tank wall (ground). Because the shielding layer can prevent the current from flowing back along the sensor to the container wall. Therefore, the ground current can only pass through the measured material to the opposite container wall through the end of the sensor.
That is, U center probe = U shielding layer, I center probe pair shielding layer = (U center probe-U shielding layer) × YL=0.
Although there is a potential difference between the shielding layer and the container wall, current flows between the two. But the current is not measured and does not affect the measurement result. In this way, the measuring terminal is protected from the influence of hanging materials. Only when the material in the container actually opens up and contacts the central probe, the measured current can be formed between the central probe and the ground through the measured material. The instrument detects this current and generates an effective output signal.
Radio frequency admittance technology introduces measurement parameters other than capacitance, especially resistance parameters. The signal-to-noise ratio of the radio frequency admittance level meter measurement signal increases. The resolution, accuracy and reliability of the radio frequency admittance level gauge are greatly improved. The diversity of measurement parameters also greatly expands the reliable application fields of radio frequency admittance level gauges.
The radio frequency admittance level gauge sensor can choose a variety of materials. Can be installed integrally or separately. Used for limit control and alarm. Welcome to contact Sino-Inst for detailed information.
There are many types of level gauges. There are heavy hammer level gauges, resistance-rotation level gauges, radio frequency admittance level gauges, diaphragm level gauges, tuning fork level gauges, vibrating rod level gauges.
They each have their own advantages and are suitable for different working conditions.
Rotary resistance level gauge
The anti-rotation level gauge can be used for the measurement of solid particles and dust. Mainly used in feed, silica, stones, spherical particles, wood chips, calcium powder, rubber, metal, limestone, grain, foundry sand, sawdust, coal powder, resin, raw leather, peanuts, clay and other materials measuring.
Radio frequency admittance level gauge
RF admittance level gauge products are widely used. Several typical occasions are as follows: the measurement of materials such as chemicals, plastics, films, feed, grain rubber medicines, liquid waste water, sand, food slurry cement, powder coating/clothing coal, granular solid oil and paper pulp.
Diaphragm level gauge
The diaphragm level gauge can be installed outside the container, whether it is installation, maintenance, equipment replacement or sensitivity adjustment. In practical applications, it is not recommended to use in the environment where the material is extremely light, viscous or large particles
Tuning fork level gauge
A dual-purpose level switch with an intelligent circuit for the tuning fork level gauge. Suitable for almost all liquids, light, easy-flowing solids
Vibrating rod level gauge
The vibrating rod level gauge can be used to monitor powder, grain or bulk materials (the diameter does not exceed 5-10cm). The density of the material must be greater than 0.05KG/DM3.
If it is lower than this density, the internal friction of the material will not be enough to weaken the amplitude of the vibration switch. This kind of vibrating level switch can be widely used in the monitoring of coal, cement, limestone, grain, sugar, fly powder and other materials.
Radio frequency admittance is a new type of level control technology with wider applicability developed from capacitive type. It is an upgrade of capacitive level technology. The so-called radio frequency admittance, the meaning of admittance is the reciprocal of impedance in electricity. It is composed of resistive components, capacitive components, and inductive components. The radio frequency is the high-frequency radio spectrum. So the radio frequency admittance can be understood as using high frequency Radio wave measurement admittance. When the meter is working, the sensor of the meter forms an admittance value with the tank wall and the measured medium. When the level changes, the admittance value changes accordingly. The circuit unit converts the measured admittance value into a level signal output to realize level measurement.
RF level sensor adopts advanced RF admittance technology. It overcomes the defect that the capacitive level meter cannot eliminate the influence of the conductive hanging material.
It is not affected by water vapor, dust or condensation, and has the advantages of stable and reliable long-term operation, high sensitivity, good linearity, high temperature resistance, and high pressure resistance.
It can be used for liquid level (level) measurement of liquid, oil and solid measurement, without moving parts.
The RF type level switch realizes the level measurement and control by sensing the change of reactance (capacitive reactance and impedance) between it and the tank body.
The internal electronic unit, the reactance between the probe measuring pole and the empty tank together form a balanced bridge circuit and generate a stable oscillating signal.
When the measured medium covers the probe measuring pole, the reactance change between the probe measuring pole and the tank will cause the bridge circuit to be unbalanced and stop generating oscillating signals. The post-stage circuit detects this change and outputs an alarm signal.
The oscillating signal is applied as a radio frequency signal at the same time as the probe’s measuring pole. It is also sent to the protection pole of the probe after passing through a 1:1 voltage follower. The radio frequency signals of the measuring electrode and the protection electrode have the same potential, the same phase, the same frequency and are isolated from each other.
When the probe is hung with material, there is no potential difference between the measuring electrode and the guard electrode to form electrical isolation to ensure that the signal change of the guard electrode does not affect the detection. The change of the reactance on the probe measuring pole can only be determined by the material between the probe measuring pole and the tank. So that the hanging material on the probe will not affect the normal detection.
Types of Level Transmitters: Level measurement transmitters are of seven types. 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 MUltrasonic Level Transmitter Guided Microwave Level Transmitters Hydrostatic level transmitters
The main function of the liquid level sensor is to detect the liquid level. The functions that can be implemented include water shortage protection, no water alarm, waterproof overflow, high liquid level reminder, etc. The liquid level sensor is used to detect the liquid level, and it is determined that the liquid level needs to be controlled at the position. Then the liquid level sensor is installed in the corresponding position. For example, the liquid level at the bottom of the container needs to be measured, and a signal reminder needs to be given when no liquid is detected. Then when the container is in a liquid state, the sensor works normally. When the liquid level drops to a low level, the liquid level sensor will give a signal reminder or alarm when it detects this industrial control change.
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Sino-Inst offers over 10 RF Admittance Level Sensors for level measurement. About 50% of these are RF level meters, 40% is the tank level sensor.
A wide variety of RF Admittance Level Sensors are available to you, such as free samples, paid samples.
Sino-Inst is a globally recognized supplier and manufacturer of RF Admittance Level Sensor instrumentation, located in China.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
Continuous level measurement and point level detection in liquids and solids with capacitance probes.
Capacitance level detectorsalso known as Capacitance level transmitter, are also referred to as radio frequency (RF) or admittance level sensors. They operate in the low MHz radio frequency range, measuring admittance of an alternating current (ac) circuit that varies with level. Capacitance level sensors are a proved, as well as a cost-effective solution forlevel measurement, and point level detection in liquids and bulk solids. Various transmitters for continuous level measurement and switches, for point level detection are available. The measurement of the interface is also possible. The measuring principle is proven in millions of applications.
Sino-Inst offers a variety of Capacitance Level Transmitters for level measurement. If you have any questions, please contact our sales engineers.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
