Sludge Flow Meter for Return Activated Sludge

A sludge flow meter refers to a flow meter that can be used to measure the flow of sludge.

What kind of flowmeter can be used for sludge flow measurement?

According to the characteristics of the sludge medium, the flow rate of the sludge can be measured by using an electromagnetic flowmeter. The electrode material uses a tantalum electrode. The lining material uses a ceramic material or tetrafluoroethylene. This can solve the flow measurement condition of the sludge.

Sludge flow meter for sludge treatment

Sludge treatment (sludge treatment) refers to the reduction, stabilization, and harmless processing of sludge such as thickening, tempering, dewatering, stabilization, drying, or incineration. The higher the degree of sewage treatment, the more sludge residues that need to be treated.

Why use an electromagnetic flowmeter to measure the sludge flow rate?

The main reason for using an electromagnetic flowmeter to solve the flow of sludge is its low cost, high measurement accuracy, and good stability. Many flows measuring instruments can meet this requirement.

Featured Sludge Flow Meters

Read more about: Different Types of Flowmeters – Technical and Application Analysis

Return Activated Sludge

The wastewater treatment plant uses a secondary treatment process called activated sludge. This process converts non-sedimentable substances into biological flocs. This substance is produced in the aeration tank and settled in the final sedimentation tank.

Activated sludge is an aerobic process. It can promote the health of microorganisms and ensure effective treatment. The balance between food and oxygen and microorganisms must be maintained for optimal treatment. An element of maintaining biomass is to return a part of the sedimentation sludge from the final sedimentation tank to the aeration tank to maintain the balance of the biological system. This part of activated sludge is called RAS (Returned Activated Sludge).

The RAS is returned to the aeration tank via a variable-speed centrifugal pump. Accurate flow rate measurement is essential to ensure that the proper ratio of “food to microorganisms” is maintained. The RAS flow rate is determined by a microbiological health laboratory analysis, and the flow rate is adjusted accordingly.

Extended reading: Insertion Ultrasonic Water Flow Meter – Designed for Agricultural Irrigation, Garden Management

Sludge Flow Measurement of Return Activated Sludge Pipe

1 Project background

  • DN 400mm stainless steel pipe;
  • Full tube
  • High pollution load, suspended solids content as high as 1%.

2 Measurement requirements

  • Trouble-free and stable measurement of the horizontal conveying pipe of the return sludge conveyed by the screw pump lifting equipment;
  • Due to high pollution load and gas load. The two existing measurements. Electromagnetic flowmeter + external clamp ultrasonic time difference method. Neither can work reliably or at all;
  • The installation cost is low.

3 Solution

  • Use NFP type cross-correlation flow measurement system;
  • A hole was drilled upstream of the existing electromagnetic flowmeter. The NFP mounting piece was welded to the existing pipeline;
  • Install a ball valve that can remove the sensor during operation, adjust and fix the cross-correlation sensor.

4 Advantages

  • Simple and fast upgrade and transformation of existing facilities;
  • The old flow measurement equipment does not necessarily need to be dismantled;
  • Although the concentration of suspended solids in the water is high, the flow measurement is still reliable.

Read more about: Shop 101: Key Factors In Selecting A Pipe Flow Meter

Extended reading: Micro flow meters for low flow liquids

Advantages of electromagnetic flowmeter in sludge measurement

  1. The electromagnetic flowmeter has no mechanical inertia. Responsive. Can measure instantaneous pulsating flow. It can also measure the flow in both directions.
  2. The output of the electromagnetic flowmeter is only proportional to the average flow rate of the measured medium. It has nothing to do with the flow state (laminar or turbulent) under symmetrical distribution. Therefore, the electromagnetic flowmeter has a very wide range. The measurement range can reach 100:1, and some even reach the operable flow range of 1000:1.
  3. The sensor structure of the electromagnetic flowmeter is simple. There are no moving parts in the measuring tube, nor any throttling parts that hinder fluid flow. So when the fluid passes through the flow meter, it will not cause any additional pressure loss. It is one of the flow meters with low energy consumption in the flowmeter.
  4. The industrial electromagnetic flowmeter has a very wide caliber range. From a few millimeters to a few meters. Moreover, there are real-flow calibration equipment with a diameter of 3m in China. Laid a foundation for the application and development of electromagnetic flowmeters.
  5. The electromagnetic flowmeter is a volume flow measuring instrument. During the measurement process, it is not affected by the temperature, viscosity, density and conductivity (in a certain range) of the measured medium. Therefore, the electromagnetic flowmeter only needs to be calibrated by water. It can be used to measure the flow of other conductive liquids.
  6. It can measure the flow of dirty medium, corrosive medium and suspended liquid-solid two-phase flow. This is because there are no obstructing flow parts inside the meter measuring tube. The fluid to be measured is only in contact with the inner lining of the measuring tube and the electrode, and the material can be selected according to the nature of the fluid to be measured.

For example, use polytrifluoroethylene or polytetrafluoroethylene as the lining. It can measure various corrosive media such as acid, alkali and salt. The use of wear-resistant rubber as the inner lining is particularly suitable for measuring liquid-solid two-phase flows such as mineral slurry and cement slurry with solid particles and greater wear, as well as various suspended liquids such as fiber-containing liquids and pulps.

Extended reading: Orifice Plate Flow Meter

Can electromagnetic flowmeter measure sludge fluid with 85% moisture content?

Yes, there is no problem at all. I am the technology of the electromagnetic flowmeter manufacturer, and the measurement is no problem. It is only when the density of the sediment particles reaches a certain level. There will be peak fluctuations. However, the measurement is no problem.

Extended reading: ultrasonic sludge level meter

Which lining material electromagnetic flowmeter is used for sludge flow meter?

What kind of flowmeter can be used for sludge flow measurement. According to the characteristics of the sludge medium, the flow rate of the sludge can be measured by using an electromagnetic flowmeter. The electrode material uses tantalum electrode, and the lining material uses ceramic material or tetrafluoroethylene. In this way, the sludge flow measurement conditions can be solved.

More about:

Learn More about Sludge Treatment

Before sludge treatment, we must first understand the classification of sludge:

  1. Treatment of physicochemical sludge discharged from sedimentation tank or thickening tank of waterworks. It is a medium and fine-grained organic and inorganic mixed sludge. The compressibility and dehydration performance are average.
  2. The remaining activated sludge discharged from the secondary settling tank of the domestic sewage plant is hydrophilic, fine-grained organic sludge, with poor compressibility and poor dehydration performance.
  3. Treatment of physicochemical and biochemical mixed sludge discharged from the thickening tank produced by industrial wastewater treatment. It is a medium-fine-grained mixed sludge. The dewatering performance of the fiber-containing body is better. The other compressibility and dewatering performance are average.
  4. The physical and chemical fine-grained sludge produced by the physical method and chemical method discharged from the thickening tank from the industrial wastewater treatment. It belongs to the fine-grained inorganic sludge. The compressibility and dewatering performance are general.
  5. Physical and chemical precipitation of coarse-grained sludge produced by industrial wastewater treatment. It belongs to coarse-grained hydrophobic inorganic sludge. It has good compressibility and dewatering performance.

Extended reading: Stainless steel flow meters|304-316 optional

You may like:

Extended Reading: Special Magnetic Flowmeter Installation situation

Sino-Inst offers Sludge flow meter products. About 85% of these are Magnetic flow meters, 3% are Ultrasonic water meters. A wide variety of Sludge flow meter options are available to you, such as free samples, paid samples.

The top-selling countries or regions are China, India, and Israel, which supply 99%, 1%, and 1% of sewage flow meter respectively. Sludge flow meter products are most popular in Domestic Market, Mid East, and North America. You can ensure product safety by selecting from certified suppliers, with ISO9001, and Other certifications.

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How to convert a 4-20mA to 0-10V /1-5V signal?

4-20mA to 0-10v voltage, this is I/V conversion. That is current-voltage conversion, usually used for long-distance signal transmission in the industry.

How to convert a 4-20mA to 0-10V /1-5V signal?

There are two methods: one is to do it yourself with an operational amplifier. The other is to buy ready-made products, such as a 4-20MA/0-10V current-to-voltage isolation converter.

4-20mA is the standard output of our measuring instrument. Such as pressure transmitter, temperature transmitter, flow meter, liquid level transmitter, and so on.

In the field of industrial measurement and control, we often encounter the following problems:

How to convert 0-5V to 4-20mA, 0-20mA or 4-24mA?

How to convert 0-10V to 4-20mA, 0-20mA or 4-24mA?

How to transform ±5V, ±10V AC voltage signal into 4-20mA, 0-20mA, or 4-24mA DC current signal?

4-20mA means that the minimum current is 4mA and the maximum current is 20mA.

The industry generally needs to measure various non-electrical physical quantities, such as temperature, pressure, speed, angle, etc. They all need to be converted into analog electrical signals before they can be transmitted to the control room or display equipment hundreds of meters away. This device that converts physical quantities into electrical signals is called a transmitter. The most widely used in the industry is to use a 4-20mA current to transmit analog quantities.

4-20mA

  • The general input impedance of 4-20mA is 250-300 ohm, which is not easy to have interfered. But maintenance measurement is more troublesome;
  • 4-20ma DC signal can provide power. In addition, it is not affected by the load size within a certain range, and has strong anti-interference ability.
  • 4-20mA can realize two-wire transmission, saving wires.
  • The current signal is suitable for long-distance transmission, but the current signal has weak anti-interference ability, and shielded wires are generally used.

0-10V

  • 0-10v are generally high-impedance inputs and are susceptible to interference. But maintenance, measurement and calculation are all very convenient.
  • 0-10V, is active, three-wire system, or four-wire system.
  • The voltage signal is stable and anti-interference is strong, but it is not suitable for long-distance transmission (with voltage drop);

The 4~20ma signal is the sensor transmission signal commonly used in industrial transmitters. It does not have a fixed-line voltage. The current is constant during transmission and the voltage changes with the load.

For our measurement and control instruments, it depends on whether your instrument wiring is a four-wire system or a two-wire system.

The four-wire system may be AC220V or DC24V;
Two-wire system or three-wire system, generally DC24V.

Read more about: What Is 0-10V Signal Output?

4-20mA standard signal conversion

Common standard analog signals are: 0-5V, 0-10V, ±5V, ±10V, 4-20mA, 0-20mA or 4-24mA. Common transmitters or sensors use one or more of the above formats to output standard signals.

Common secondary meters or acquisition cards generally accept input signals of one or more of the above formats.

When the output signal of the transmitter or sensor is different from the input signal format of the secondary instrument or acquisition card, we need to add a converter between them.

Because the 4-20mA standard signal has the advantages of strong anti-interference ability and no attenuation in the transmission process, it has been widely used in the field of measurement and control.

Often in order to achieve interface compatibility or improve electromagnetic compatibility, it is necessary to convert 0-5V, 0-10V and other standard voltage signals into 4-20mA standard current signals. Or the 4-20mA current signal needs to be converted into a 0-5V or 0-10V standard voltage signal suitable for the input of the acquisition card.

How to convert a 4-20mA to 0-10V /1-5V signal?

I have a pressure transmitter here that outputs a current of 4-20mA. As the input signal of the inverter. Now it is required to change the input signal of the inverter to a voltage signal. That is, the current of 4-20mA should be replaced with a voltage of 0-5V or 0-10V. The inverter has two inputs: 0-5V and 0-10V. Excuse me, how can it be transformed?

Answer: There are two schemes to achieve:

1.Use a hardware circuit to convert the input 4-20mA current signal into 0-5V or 0-10V voltage signal. See the circuit diagram below:

Connection:

  1. Select the A input port: connect A+ and RA together, connect an external 4-20mA current input signal, and connect the A- terminal to the PLC common point M. A input port is set to 0~20mA current input mode.
  2. The analog output port uses voltage output port V0, its M0 port is connected to the common terminal M, and the output port is set to voltage output mode: 0~10V (or 0~5V).

2.Use a signal converter

The signal converter converts the DC current or voltage signals of various devices on the site into the required DC signals for isolation and transmission and then outputs them to other instruments. The signal isolator can effectively eliminate ground return. Solve the problems of industrial field interference and signal conversion, transmission, and matching.

It is widely used in data acquisition, signal transmission and conversion, PLC, DCS, and other industrial measurement and control systems in electrical, power, telecommunications, steel, petrochemical, sewage treatment, environmental protection engineering, aerospace, building automation, and other fields. It is used to complete and supplement the system simulation I/O plug-in function. Increase
The applicability of the system and the reliability of the on-site environment.

Main Specifications

  • Measurement: DC current, DC voltage, etc.
  • Accuracy: ≤±0.1% F·S
  • Power consumption: <1W (when 24VDC power supply)
  • Impedance: current input ≤100Ω, voltage input ≥500KΩ
  • Power supply: DC24V, AC220V or customized
  • Isolation: Input, output, and power supply are completely isolated
  • Support live hot swap operation. Easy to unload, high precision, high linearity, strong anti-interference
  • Long-term work stability
Input signalEnter parameter codeOutput 1Output 2Power supply
A DC power supply
V DC voltage
Current Range
A420 4-20mA
A020 0-20mA
A010 0-10mA
T customer self-determined;

Or voltage range
V0100-10V
V15 1-5V
V075 0-75mV
V6
0-600V
T customer self-determined
V010 0-10V
V15 1-5V
A4204-20mA
A0100-10mA
T customer self-determined
V0100-10V
V151-5V
A420 4-20mA
A0100-10mA
T customer self-determined
No input
D DC24V
A AC220V
T customer self-determined

No matter which WaterFlow Meters you choose. The signal output by WaterFlow Meters, such as 4-20mA. The flow signal can be connected to a paperless recorder. Carry out multi-channel flow signal monitoring.

Our paperless recorder, also known as Digital Chart Recorder. also has such a function. Support signal input and output. You can configure appropriate functions according to your own needs. What Is A Digital Chart Recorder?

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Sino-Instrument offers a variety of transmitters and sensors that support signal output. Including 4-20mA, 0-10V, 1-5V, etc.

About 30% of these are 4-20ma Pressure Transducers, 30% are Flow Meters, and 20% are Level Transmitters, 20% are 4-20ma Temperature transmitters.

Sino-Instrument is a globally recognized supplier and manufacturer of Pressure Transducers, located in China.

The top supplying country is China (Mainland), which supply 100% of Pressure Transducers respectively.

Sino-Instrument sells through a mature distribution network that reaches all 50 states and 30 countries worldwide.

Low-Pressure Transducers products are most popular in Domestic Market, Southeast Asia, and Mid East.

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

Laser Level Transmitter

What is a laser level transmitter?

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

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

The laser level transmitter is a non-contact level gauge. The product is powerful, sturdy and durable. It has excellent accuracy and high stability. It achieves accurate, non-contact and uninterrupted real-time monitoring of material height. Industrial site and process, river water level monitoring, material height monitoring and other occasions have very broad applications.

Laser level transmitter Main features:

  • Abundant output interfaces: TTL, RS232, RS485, 4~20mA, CANBUS, ModBus, 0~5V, 0~10V;
  • Ultra-wide power supply voltage: 6~36V DC;
  • The resolution is 0.1mm, and the single acquisition accuracy is better than 1mm;
  • Protection grade: IP67 (anti-salt fog, mildew, anti-collision treatment);
  • Built-in over-current automatic recovery, anti-reverse connection, anti-surge and lightning protection;
  • Non-contact measurement technology, less affected by the working environment, easy to install, layout and back-end control;
  • In an outdoor environment, it can still maintain high measurement accuracy and reliability;
  • The sensor can be processed into a fully sealed, convenient to use in harsh environments;
  • It can be powered by vehicle power supply and industrial DC power supply;
  • Stable power consumption, very low power consumption (when there is no current alarm, the power consumption is less than 1W);
  • Standard industrial bus interface, with operating software to realize all-round industrial automation control;
  • Liquid level and material level height monitoring;
  • It can be equipped with Bluetooth, GPRS, WIFI, rechargeable lithium battery and other functions.

Extended reading: Float Level Sensors – Single and Multipoint

Laser level transmitter data:

Shortest distance0.05m
The longest distance [indoor]10m  20m  40m  80m  200m
Precision±1mm; single measurement accuracy is better than 1mm
Resolution0.1mm
Output frequencyUp to 8Hz
laserVisible laser
Laser classClass Ⅱ safety laser
Laser wavelength635nm~650nm
Spot diameter10m@10mm
Laser life>50000h
AnnotationPlease do not stare into the beam, avoid contact with the laser, according to EN60825-1:2003-10 standard
Input voltageDC6-36V
Whole machine power consumption<1W
Digital outputRS485, RS232, TTL, CANBUS, ModBus
Analog output4-20mA, 0~5V, 0~10V
Instrument size80mm*63.4mm*32mm
Shell materialAluminum black anodized
weight200g
Protection levelIP67
Operating temperature-15℃…+50℃
storage temperature-30℃……+70℃

Laser level transmitter Applications:

Application range:

  • Liquid asphalt, polymerization reactor vessel (high pressure),
  • Reactor vessel (vacuum), molten glass, ferrous and non-ferrous metals,
  • Alloy polystyrene, nylon, polychloride and other core blocks, talcum powder or lime powder,
  • Ore, waste rock in ore chute, wet or dry wood chips;
  • Mining, chemical industry;
  • High-risk areas such as pharmaceuticals, papermaking, plastics, oil and gas, etc.

Restrictions on use: poor accuracy or uselessness under foggy conditions

ElementFactors that extend the measuring rangeFactors that shorten the measuring range
Target surfaceThe brightly reflective surface, such as reflectorDim and matte surface, green and blue surface
Air particlesClean airDust, fog, heavy rain, blizzard
Daylight intensityDark environmentThe target is brightly illuminated
  • Rough surface: When measuring rough surfaces (such as plaster walls), aim at the center of the shiny area.
  • Transparent surface: Please do not measure on the surface of transparent objects, such as colorless liquids (such as water) or glass (no dust).
  • Oblique round surface: The measurement can only be performed when the target area is large enough to accommodate the laser spot.

Extended reading: Hydrostatic Level Measurement

Extended reading: What is Modbus Protocol?

Laser level transmitter working principle

The laser level transmitter adopts the phase method laser ranging technology. Using the frequency of the radio band, the laser beam is amplitude modulated and the phase delay produced by the modulated light going back and forth to the measuring line is measured. Then according to the wavelength of the modulated light, the phase delay represented by this is converted distance. That is, the indirect method is used to measure the time required for the light to pass through the measuring line.

The distance D from the surface of the material is proportional to the time travel T of the pulse:

D=C×T/2

Where C is the speed of light

Since the distance E of the empty tank is known, the level L is:

L=E-D

According to the range and full scale information set by the user, the processor calculates the percentage of the current material level, and then outputs 4-20mA or 0-5V analog signals, RS485 Modbus digital signals, and warning alarm relay switch signals in proportion.

Advantage:

  • The measuring beam has a small divergence angle and good directivity;
  • Large range, long-distance measurement, minimum blind spot;
  • Not affected by the temperature of the medium;
  • Non-intrusive measurement, non-contact measurement;
  • Fast measurement speed, suitable for fast-changing liquid level and material level measurement;
  • Easy to use, programmable measurement;
  • Accurate measurement and high precision are suitable for high-demand projects;
  • The resolution is ten times higher than the general table;
  • The beam angle is small, suitable for long-distance positioning and avoiding obstacles.

Disadvantages:

  • Easy to be interfered by the light source in the test band and absorbed by the dark object;
  • Slightly more expensive

Extended reading: Ultrasonic Level Switch-External Mounted

Extended reading: Magnetostrictive Level Transmitter Advantages And Disadvantages

Laser-level measurement has gained popularity in industrial applications. The advantage of laser level measurement is an accurate and simple measurement without contact with the measured material. Even materials with a low dielectric constant can be easily measured with a laser transmitter.

The laser beam is very narrow (divergence <0.3°), and a small spot is formed on the surface, which is usually less than 30cm even at a long distance. The figure below shows a typical installation on the storage bin. The laser transmitter is mounted on the reel using a rotating flange to ensure precise alignment to the bottom of the silo. In order to strengthen the protection, a dustproof tube is also used. For plastic applications, it is important to use metal mounting plates or flanges and ensure that they are properly grounded to the silo to help eliminate static buildup.

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

Extended reading: Radar Level Sensor Advantages and Disadvantages

In order to use water resources rationally, real-time detection of the water level of various water areas is particularly important, so the demand for water level gauges is huge.

The laser level meter is a new type of distance measuring equipment with the advantages of high accuracy, fast response, large range, non-contact measurement, etc. It is suitable for my country’s rivers, lakes, reservoirs, hydraulics, ship locks, rivers, urban water and other liquid level monitoring occasions.

Extended reading: Ultrasonic level transmitter for Hazardous Liquids

Extended reading: Capacitive water level sensor

There are many different ways to measure the level of liquid in a tank, but laser tank level measurement is becoming increasingly popular. This is because laser tank level measurement is more accurate than other methods, and it is also much easier to install and maintain.

Laser tank level measurement works by sending a laser beam across the surface of the liquid in the tank. The laser beam is reflected off the surface of the liquid, and the time it takes for the laser beam to return to the sensor is measured. This time can then be used to calculate the level of the liquid in the tank.

One advantage of laser tank level measurement over other methods is that it is not affected by the temperature or density of the liquid. This means that it can be used to measure the level of liquids with very different properties, such as water and oil.

Another advantage of laser tank level measurement is that it is not affected by the build-up of sediment on the bottom of the tank. This can be a problem with other methods, such as ultrasonic level measurement, which rely on sound waves to measure the level of liquid.

Laser tank level measurement is also much easier to install than other methods. This is because there are no moving parts, and the laser beam can be directed through a small hole in the top of the tank. This means that laser tank level measurement can be used in tanks that are difficult to access, such as those in underground storage facilities.

If you are looking for a reliable and accurate way to measure the level of liquid in a tank, laser tank level measurement is the ideal solution.

Extended Reading: Silo/Bin material level measurement system

Read More About: Ultrasonic tank level bottom sensor

More Featured Liquid Level Sensors and Measurement Solutions

More Featured Solids Level Sensors and Measurement Solutions

Extended reading: Ultrasonic Oil Level Sensor-External Paste-Truck Fuel Tank

Laser Level Transmitter is a large-range, high-accuracy explosion-proof level measurement product supplied by Sino-Inst. It has the functions of level measurement, average temperature measurement, switch alarm output, and can be displayed beside the tank. The product structure is reasonable, the precision is high, and the maintenance rate is low.

Laser Level Transmitter can measure media and application methods: particles, lumps, viscosity, water conservancy, distance measurement, liquid level measurement, material level measurement and other working conditions.

Laser Level Transmitter application scale:
Liquid asphalt, polymerization reactor vessel (high pressure), reactor vessel (vacuum), molten glass, black and non-ferrous metals, alloy polystyrene. Pellets such as nylon, polyvinyl chloride, talc or lime powder, ores, waste rock from draw chutes, wet or dry wood chips. Mining, chemical. High-risk areas such as pharmaceuticals, paper, plastics, oil and gas.

Sino-Inst offers over 50 level transmitters for level measurement.

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

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

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

Type k thermocouple chart

A thermocouple chart is a practical tool for the electronic query of temperature index. It is used by technicians who are engaged in automatic control of the production process.

To simply look at it means: when 0 is the reference temperature and the measured temperature is the sum of the row and column temperatures, the measured thermoelectric potential is the value.

How do you read a K type thermocouple table?

In the thermocouple chart, the first row and the first column are all temperature values.
The rows are incremented by 10 degrees per grid.
The columns are incremented by 100 degrees per grid.
The intersection of the row and the column is the thermoelectric potential value at the current temperature.

Take the S-type couple to read the thermoelectric potential value at 280 degrees Celsius for example: first find 200 degrees from the first column, and draw a straight line to the right.
Then find 80 degrees from the first line and draw a straight line down. Where the two lines meet, the thermoelectric potential value at 280 degrees is 2.141 millivolts.

Type K thermocouple chart

K Reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
003977981203161120222436285032663681
1004095450849195327573361376539693973387737
200813785378938934197451015110560109691138111793
30012207126231303913456138741429214712151321555215974
40016395168181724117664180881851318938193631978820214
50020640210662149321919223462277223198236242405024476
60024902253272575126176265992702227445278672828828709
70029128295472996530383307993121431629320423245532866
80033277336863409534502349093531435718361213652436925
90037325377243812238519389153931039703400964048840879
100041269416574204542432428174320243585439684434944729
110045108454864586346238466124698547356477264809548462
120048828491924955549916502765063350990513445169752049
13005239852747530935343953782541255446654807
  

  

Type N thermocouple chart

N reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
00261525793106513401619190221892480
1002774307233743680398943024618493752595585
2005913624565796916725575977941828886378988
300934196961005410413107741113611501118671223412603
40012974133461371914094144691484615225156041598416336
50016748171311751517900182861867219059194471983520224
60020613210032139321784221752256622958233502374224134
70024527249192531225705260982649126883272762766928062
80028455288472923929632300243041630807311993159031981
90032371327613315133541339303431934707350953548235869
100036256366413702737411377953817938562389443932639706
110040087404664084541223416004197642352427274310143474
120043846442184458844958453264569446060464254678947152
130047513
  

  

  

  

  

  

  

  

Type E thermocouple chart

E Reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
0059111921801241930473683432949835646
10063176996768383779078978710501112221194912681
20013419141611490915661164171717817942187101948120256
30021033218142259723383241712496125754265492734528143
40028943297443054631350321553296033767345743538236190
50036999378083942640236410454185342662434704427845085
60045085458914669747502483064910949911507135151352312
70053110539075470355498562915708357873586635945160237
80061022618066258863368641476492465700664736724568015
90068783695497031371075718357259373350741047485775608
100076358
  

  

  

  

  

  

  

  

  

Type J thermocouple chart

J Reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
0050710191536205825853115364941864725
10052685812635969077457800885609113966710222
20010777113321188712442129981355314108146631521715771
30016325168791743217984185371908919640201922074321295
40021846223972294923501240542460725161257162627226829
50027388279492851129075296423021030782313563193332513
60033096336833427334867354643606636671372803789338510
70039130397544038241013416474228342922435634420744852
80045498461444679047434480764871649354499895062151249
90051875524965311553729543215494855553561555675357349
100057942585335912159708602936087661459620396261963199
110063777643556493365510660876666467240678156839068964
120069536
  

  

  

  

  

  

  

  

  

Type T thermocouple chart

T reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
003917891196161120352467290833573813
1004277474952275712620467027207771882358757
200928698201036010905114561201112572131371370714281
300148601544316030166211721717816
  

  

  

  

Type S thermocouple chart

S Reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
0055113173235299365432502573
10064571979587295010291109119012731356
2001440152516111698178518731962205121412232
3002323241425062599269227862880297430693164
4003260335634523549364537433840393840364135
5004234433344324532463247324832493350345136
6005237533954425544564857515855596060646169
7006274638064866592669968056913702071287236
8007345745475637672778278928003811482258336
9008448856086738786889990129126924093559470
10009585970098169932100481016510282104001051710635
110010754108721099111110112291134811467115871170711827
120011947120671218812308124291255012671127921291313034
130013155132761339713519136401376113883140041412514247
140014368144891461014731148521497315094152151533615456
150015576156971581715937160571617616296164151653416653
160016771168901700817125172451736017477175941771117826

Type R thermocouple chart

R Reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
0054111171232296363431501573
10064772380087995910411124120812941381
2001469155816481739183119232017211222072304
3002401249825972696279628962997309932013304
4003408351236163721382739334040414742554363
5004471458046904800491050215133524553575470
6005583569758125926604161576273639765076625
7006743686169807100722073407461758377057827
8007950807381978321844685718697882389509077
9009205933394619590972098509980101111024210374
100010506106381077110905110391117311307114421157811714
110011850119861212312260123971253512673128121295013089
120013228133671350713646137861392614066142071434714488
130014629147701491115052151931533415475156161575815899
140016040161811632316464166051674616887170281716917310
150017451175911773217872180121815218292184311857118710
160018849189881912619264194021954019677198141995120087
170020222203562048820620207492087721003
  

  

  

Type B thermocouple chart

B reference terminal temperature: 0℃, 10 degrees μν value

0102030405060708090
00-2-3-2026111725
100334353657892107123140159
200178199220243266291317344372401
300431462494529561596632669707746
40078682787091395710021048109511431192
5001241129213441397145015051560161716741732
6001791185119121974203621002164223022962363
7002430249925692639271027822855292830033078
8003154323133083387346635463626370837903873
9003957404141264212429843864474456246524742
10004833492450165109520252975391548755835680
11005777587559736073617262736374647565776680
12006783688769917096720273087414752176287736
13007845795380638172828383938504861687278839
14008952906591789291940595199634974898639979
150010094102101032510441105581067410790109071102411141
160011257113741149111608107251184211959120761219312310
170012436125431265912776128921300813124132391335413470
1800135851369913814
  

  

  

  

  

  

  

Download: K thermocouple chart

The working principle of thermocouple (thermocouple principle)

What is a thermocouple?
This is to start with the principle of thermocouple temperature measurement. The thermocouple is a kind of temperature sensing element and a primary instrument. It directly measures temperature and converts the temperature signal into a term electromotive force signal. It is converted into a term electromotive force signal by an electrical instrument (secondary instrument). The temperature of the measured medium.

The basic principle of thermocouple temperature measurement is that two different components of material conductors form a closed loop. When there is a temperature gradient at both ends, there will be a current passing through the loop, and then there is Seebeck electromotive force-term electromotive force between the two ends. This is the so-called Seebeck effect.

Two homogeneous conductors with different compositions are term electrodes, the end with a higher temperature is the working end, and the end with a lower temperature is the free end, which is usually at a certain constant temperature. According to the functional relationship between term electromotive force and temperature, a thermocouple index table is made. The index table is obtained when the free end temperature is at 0℃. Different thermocouples have different index tables.

When the third metal material is connected in the thermocouple circuit, as long as the temperature of the two junctions of the material is the same, the thermoelectric potential generated by the thermocouple will remain unchanged, that is, it will not be affected by the third metal in the circuit. Therefore, when the thermocouple measures the temperature, it can be connected to the measuring instrument, and after the term electromotive force is measured, the temperature of the measured medium can be known.

The working principle of thermocouple:

Two conductors with different components (called thermocouple wires or thermoelectrodes) are connected at both ends to form a loop. When the temperature of the junction is different, an electromotive force will be generated in the loop. This phenomenon is called the thermoelectric effect. And The electromotive force is called thermoelectric force.

Thermocouples use this principle for temperature measurement. One end that is directly used to measure the temperature of the medium is called the working end (also called the measuring end), and the other end is called the cold end (also called the compensation end). The cold end and the display instrument or When the matching instrument is connected, the display instrument will point out the thermoelectric potential generated by the thermocouple.

A thermocouple is actually a kind of energy converter, which converts heat energy into electrical energy. Use the generated thermoelectric potential to measure temperature. Regarding the thermoelectric potential of a thermocouple, you should pay attention to the following issues:

  1. The thermoelectric potential of a thermocouple is a function of the temperature difference between the two ends of the thermocouple. It is not a function of the temperature difference between the two ends of the thermocouple;
  2. The size of the thermoelectric potential generated by the thermocouple. When the material of the thermocouple is uniform, it has nothing to do with the length and diameter of the thermocouple, but is only related to the composition of the thermocouple material and the temperature difference between the two ends;
  3. When the two thermocouple wires of the thermocouple have determined the material composition. The thermoelectric potential of the thermocouple is only related to the temperature difference of the thermocouple. If the temperature of the cold junction of the thermocouple remains constant, the thermoelectric potential of the thermocouple is only Single-valued function of working end temperature.

Sino-Inst, Manufacturer 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, the US, and other countries.

Paddle wheel flow meter technology

What is a Paddle wheel flow meter?

Paddle wheel flow meter is a mechanical flow meter that uses an impeller as a flow sensor component. The impeller-type flow meter is a meter that measures flow according to the principle of fluid momentum moment. Paddle wheel flow meter is also called an impeller flow meter, rotary wheel flow meter, etc. Typical Paddle wheel flow meters are water meters and turbine flow meters. It can be a mechanical transmission output type or an electric pulse output type. It is suitable for the measurement and control of industrial process clean water pipelines or low-concentration acid-base, low-viscosity single-phase fluid non-trade settlement process.

Paddle wheel flow meter Features

  1. Has good anti-interference
  2. Strong signal transmission capability (the farthest transmission is 300 meters)
  3. Stable quality and low failure rate
  4. Superior performance-price ratio
  5. Wide range measurement.
  6. All measurement parameters can be adjusted independently.
  7. Output 4-20mA or RS485 communication output, two pairs of alarm output contacts.
  8. Display real-time flow and cumulative flow.
  9. Insertion installation.

Application range of impeller flowmeter

  • Flow monitoring of industrial water treatment process
  • Industrial circulating cooling water and make-up water flow monitoring
  • Reclaimed water flow monitoring
  • Process flow monitoring after wastewater treatment
  • Agricultural irrigation water flow measurement
  • Multi-way valve and multi-valve system flow monitoring for softening, filtering, etc.
  • Other water flow detection and control

Extended reading: Insertion Ultrasonic Water Flow Meter – Designed for Agricultural Irrigation, Garden Management

Paddle wheel flow meters parameters

Picture
ModelKF11 Corrosion-resistant flow sensorKF11 series impeller flow meter
DescriptionSuitable for highly corrosive fluids, sulfuric acid, nitric acid, hydrofluoric acid, hydrochloric acid, mixed acid, strong alkali and other places;
The flow parts are made of corrosion-resistant materials such as PVDF·PTFE·Hastelloy·Titanium alloy; there is almost no pressure loss and maintenance-free;
Flow velocity range 0.3-6m/s, can measure fluid with flow velocity greater than 0.3m/s;
Not applicable to media containing particles and fibrous impurities;
The impeller adopts a five-piece runner design
PP/PVDF/PTFE material
Better guarantee the dynamic balance characteristics, greatly improving the linear accuracy and repeatability accuracy of the sensor;
The minimum flow rate is 0.1m/s; NPN open collector output, which can be directly transmitted to a flow transmitter or PLC, a standard square wave signal and a maximum distance of 300m;
Applicable caliber: DN25-DN600 (1″-24″);
Not suitable for particles and fibrous impurities
The medium;
Caliber rangeDN25-DN600(1″-24″)DN25-DN600(1″-24″)
Flow rate range0.3-5m/s0.1-8m/s
Output signalSquare wave pulse signal: (40-45Hz) nominal flow rate per m/sSquare wave pulse signal: (40-45Hz) nominal flow rate per m/s
Equipped with pulse conversion components can output 4-20mA
CharacteristicHall pulse output, open collector NPN, strong driving ability
Has high chemical resistance
Minimum flow rate 0.3m/s
IP68 protection grade suitable for harsh on-site environment
Hall pulse output, open collector NPN, strong driving ability
Has high chemical resistance
IP68 protection grade suitable for harsh on-site environment
Plug-in type, easy installation, good reliability, almost maintenance-free
Linear accuracy L
Repeatability accuracy R
L=±1%
R=±0.5%
L=±1%
R=±0.5%
OntologyPVDF/PTFEPP plus glass fiber/CPVC
ImpellerPVDF/PTFEPP/PVC/PVDF/PTFE
Shaft and bearingHastelloy C/Titanium Alloy/ZrO2Al2O3/ZrO2/SS316L/Hastelloy C/Titanium Alloy
O-ringfluororubberFPM/EPDM/Fluorine rubber
Temperature and pressurePVDF body: 12.5bar@25℃-2.5bar@100℃
PTFE body: 12.5bar@25℃-2.5bar@100°
PP body: 12.5bar@25℃-1.7bar@80℃
CPVC body: 12.5bar@25℃-1.7bar@80℃
Power supply systemDC 5-24VDC5-24V
Protection levelIP68IP68
Application fieldSulfuric acid ratio and delivery flow monitoring
Copper sulfate monitoring in electroplating bath
Nitric acid mixture
Intermediate
Chemical waste
Pure Water Process/Reverse Osmosis/Ultrafiltration/EDI
Water purification and filtration system
Cooling water and boiler water monitoring
Chemical industry
Agricultural irrigation
Cleaning system and single crystal silicon cleaning
Pump protection

Check more Choosing The Right 1 Inch Flow Meter.

Paddle wheel flow meter working principle

The sensor is divided into two parts: the transmitter and the impeller. The impeller is in direct contact with the fluid, and the transmitter is isolated from the fluid. The liquid flow drives the impeller to rotate, and there are four evenly distributed magnetic blades on the impeller. The rotating magnetic blade induction Hall switch generates a frequency signal proportional to the flow rate, and the transmitter converts the frequency signal into a 4-20mA current signal.

Typical Paddle wheel flow meters are water meters and turbine flow meters. The structure can be a mechanical transmission output type or an electric pulse output type.

The accuracy of water meters with general mechanical transmission output is low, with an error of about ±2%. However, the structure is simple and the cost is low. It has been mass-produced in China, and is standardized, generalized and serialized. The accuracy of the turbine flowmeter output by the electric pulse signal is relatively high, and the general error is ±0.2%-0.5%

The five-piece impeller design is in line with the principle of fluid mechanics, and the uniform force angle produces a better dynamic balance, ensuring better linear accuracy and repeatability accuracy

Various shafts and bearings:
Shaft and bearing: ZrO2, SS316L, Hastelloy C
Impeller material: PTFE, PP, PVDF, ABS
Body material: PP plus glass fiber, ABS, CPVC, PTFE, SS316L, brass

Real flow calibration
Calibration range: DN10-DN1000
Each sensor has undergone strict calibration and quality inspection. When leaving the factory, each sensor guarantees that the K factor is 2% of the standard value, and the repeatability accuracy is 0.5%;

Read more about: What is an inline flow meter?

Paddle wheel flow meter advantages and disadvantages

Advantage

  • Excellent reproducibility and responsiveness.
  • Simple structure and low price.
  • Small size, large-capacity measurement is possible.

Disadvantage

  • Extremely sensitive to foreign objects. (Causing blockage)
  • Due to the high-speed rotation of the impeller, regular maintenance is required to cope with axial wear or to replace the impeller.

Extended reading: How to Select the Right Agriculture Flow Meter

Paddle wheel flow meter installation

  • The straight section behind the flange must meet the measuring distance of the first 10 and the rear 5 times the pipe diameter;
  • After reducing the diameter (only allowed to change from large to small, but not allowed to change from small to large), the straight line segment needs to meet the measurement distance of the first 15 and the back 5 times the pipe diameter;
  • The straight section behind the first-level equal-diameter elbow needs to meet the measuring distance of the first 20 and 5 times the pipe diameter;
  • The straight section behind the two-stage continuous equal-diameter elbow on the same plane must meet the measurement distance of the first 25 and the rear 5 times the pipe diameter;
  • The straight section behind the non-coplanar two-stage continuous equal-diameter elbow needs to meet the measuring distance of the first 40 and the back 5 times the pipe diameter;
  • The straight section behind the valve must meet the measurement distance of the first 50 and the last 5 times the pipe diameter;
  • The probe is recommended to be installed perpendicular to the pipe, and not at the bottom of the pipe;
  • The probe can be installed on a vertical pipe where the liquid flows upward, but it must also meet the requirements of the above-mentioned straight section;
  • The probe is not allowed to be installed on a vertical pipe where the liquid flows downward;
  • The liquid in the tested pipeline must be full of flow, and no gas and liquid can flow at the same time;
  • The cost of the body must be consistent with the bayonet (open slot) to ensure the correct installation position;
  • The O-ring has a good sealing effect. When the installation is tight, it needs to be wetted with silicone oil or water for installation;
  • The sensor locking cap must be tightened to prevent excessive pressure in the pipeline from leaking or ejecting;
  • When installing outdoors, pay attention to waterproof treatment; keep the cables dry to avoid moisture damage;
  • Do not lay the sensor cable and AC power cable in the same protective tube to avoid electrical interference

Extended reading: Industrial VS Residential inline water flow meters

More Featured Paddlewheel flowmeters

You may like:

Sino-Inst, paddle wheel flow meter manufacturer. It can measure a single sound-conducting liquid medium of Velocity range: 0.1~6m/s; Pipe diameter: DN15 to DN600.

Sino-Inst’s paddle wheel flow meter, made in China, Having good Quality, With a better price. Our flow measurement instruments are widely used in China, India, Pakistan, the US, and other countries.

How Does a Piston Flow Meter Work?

What is a piston flow meter?

A piston flow meter is a positive displacement flowmeter, which is mainly used to measure liquid flow. The piston flow meter is composed of a shell, piston mechanism, and other parts. The measured fluid fills a space with a certain volume, and these volume increments are counted and accumulated. It has the advantages of simple structure, reliable work, high accuracy, large range ratio, and little influence on viscosity. It is mostly used for measuring non-corrosive liquids, such as heavy oil or other oils, on small-diameter pipelines.

Piston flow meter technology

Piston-type flowmeters are commonly used for flow measurement of fuel dispensers. Its structure includes a housing, an upper cover, a lower cover, a piston, a crankshaft, and a distribution valve. The inner cavity of the housing is equipped with four-piston cylinders that cooperate with the piston dynamic seal. The four-piston cylinders are evenly distributed in the circumferential direction on the vertical plane of the crankshaft rotation centerline.

The piston is connected to the crankshaft by a connecting rod. The piston rodless cavity is connected to the inlet and outlet on the upper cover through the distribution valve. A side cover is installed on the casing outside the piston cylinder. The upper cover is equipped with an output shaft that rotates synchronously with the crankshaft. By right Count the number of revolutions of the output shaft to achieve flow measurement.

  • The main disadvantages are:
  • The outer circular surface of the output shaft of the existing piston flowmeter and the upper cover adopts O-ring dynamic sealing cooperation.
  • The high-speed rotation of the output shaft is likely to cause wear to the sealing ring, resulting in a decrease in sealing performance and even leakage.
  • In addition, there are errors in the machining dimensions of the inner cavity of the piston-cylinder of each product. Lead to the measurement error of the piston flowmeter.

Read more General-purpose Flow Totalizer for Data collection and calculation

Features and applications of Piston flow meter

The piston flow meter has a simple structure, reliable work, and a large measuring range.
The measurement accuracy is high and is not affected by viscosity. It can be changed remotely and other advantages.

However, the main components of the measurement part are not corrosion-resistant. Therefore, it can only measure non-corrosive media, such as heavy oil and other petroleum products.

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

Piston flow meter working principle

A piston flow meter is a positive displacement flow meter, which is based on the fact that the piston and the metering chamber have been kept in a tangential sealed state. And there is a fixed eccentric distance metering element piston.

Under the action of the pressure difference, a rotational torque is generated on the piston, which makes the piston perform an eccentric rotation movement.

The number of revolutions of the piston is proportional to the flow rate of the fluid. The piston revolution ratio is recorded by the counting mechanism. Then the total flow of fluid can be measured.

The inlet and outlet of the Piston flow meter are separated by a partition. When the measured fluid enters the metering chamber from the inlet, a pressure difference is formed at the inlet and outlet, forcing the piston to rotate counterclockwise as shown in the figure.

The continuous flow of fluid forces the piston to rotate as shown in the figure, forming two and a half-crescent cavities. The piston is forced to rotate under the action of the pressure difference as shown in the figure. V2 fluid is discharged from the outlet. Rotate under the action of pressure difference. V1 fluid is discharged from the outlet, and the fluid bursting out every revolution of the piston is equal to the sum of V1+V2.

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

Piston flowmeter output signal, such as 4-20mA. The flow signal can be connected to a paperless recorder. Carry out multi-channel flow signal monitoring. What Is A Paperless Recorder?

Piston flowmeter VS gear type flowmeter

Gear flow meters are a type of positive displacement flow meters, used for precise continuous or intermittent measurement of the flow or instantaneous flow of liquid in the pipeline. It is especially suitable for the flow measurement of heavy oil, polyvinyl alcohol, resin, and other high viscosity media.

Piston type flowmeter is an online installation, mechanical flow switch, used for liquid or gas medium. Very small pressure loss, good repeatability, anti-fouling ability, mechanical part, and electronic part are completely isolated, suitable for small flow economy type.

If the flow rate you want to measure is not large, the piston type is better.
If you want to measure a large flow rate, just use a gear type.
If the gas flow is measured, only the piston type can be used

Extended reading: Positive displacement flow meter working principle.

Guess you like: What is Reynolds number?

A Piston Flow Meter is an innovative device that accurately measures fluid flow in pipelines. Sino-Inst, a well-established manufacturer and supplier of Piston Flow Meters, boasts a wealth of experience in the field.

With our top-notch product line, Sino-Inst is the perfect partner for all your flow measurement needs. If you’re in the market for a reliable and efficient Piston Flow Meter, look no further! Contact Sino-Inst today and let them show you what they can do.

And that’s not all, Sino-Inst also offers a range of other flow meters, including turbine flow meters, magnetic flow meters, and more. Let Sino-Inst help you find the perfect flow meter solution for your specific application!

Powder Silo/Bin Level Measurement and Control System

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

The importance of Silo/Bin level monitoring

In the production process of the mixing station, the material in the powder silo is replenished in time by means of pneumatic conveying. Most of the dust collectors on the top of the powder silo of the mixing station lack normal maintenance. During the replenishment of the tank body, the pressure of the powder silo is too high, causing “roof fall”. Cement overflows from the dust collector or safety valve. Or “lift the top”, the separation of the top cover of the powder silo from the body of the powder silo occurs.

The intelligent safety system of the powder silo passes through the intelligent detection equipment installed on the silo. achieve:

  • Predict the amount of storage in the warehouse and control the amount of feed;
  • Three-level protection to prevent the occurrence of “top falling” and “lifting top” accidents;
  • Prevent the wrong storage of cement, fly ash, and mineral powder, and prevent construction quality accidents;
  • Cloud platform monitoring platform, real-time monitoring of the status parameters of the powder silo;

Extended Reading: What is level transmitter working principle?

Silo/Bin material level measurement system

System Features

  • Instead of “manual hammering”, the remaining amount of materials in the warehouse can be controlled at any time to provide a basis for procurement and inventory;
  • The resistance rotary switch is intelligently controlled, and the signal is incorporated into the material level measurement system, which greatly extends its service life;
  • Real-time alarm on the feeding surface when feeding, to prevent the occurrence of “roof fall” accidents;
  • The application of product intelligent diagnosis algorithm solves the difficulties of heavy hammer level gauges in the industry that it is too faulty and difficult to maintain;
  • The control system adopts a distributed network system, wireless transmission, stable and reliable, and fast wiring;
  • Reserved information interface to meet the needs of remote control and ERP management system;
  • Distributed control system layout, display the working status of the entire system and equipment parameters on the touch screen;

Extended reading: PID Controller Working Principle

Important components of the system

  1. High-altitude material level detector

Installed on the top of each silo, it is the main measuring equipment of the material level measuring system. It can more accurately monitor the amount of storage in the warehouse in real time, and has the characteristics of resistance to heavy dust and long service life.

  1. High-performance anti-rotation level switch

The anti-rotation material level switch is installed vertically downward to detect whether the motor is working. Through the safety feeding valve to start and stop the rotation resistance, the service life is extended to 3-5 years; with the central control touch screen alarm and the ground terminal alarm, it can effectively prevent the occurrence of “top falling” accidents.

  1. Central control system

It adopts a 15-inch touch LCD screen, an embedded operating system, and is equipped with the material level measurement system software independently developed by the company. The equipment adopts 485 communication interface, which has the characteristics of fast transmission rate, high signal strength, and low failure rate.

  1. Ground display terminal

One set is equipped at the bottom of each silo, which is used for sound and light alarm when the material level triggers the anti-rotation switch alarm (synchronized with the weighing room alarm), real-time display of material weight and percentage, promptly reminding the operator to take measures to avoid accidents.

  1. Safety feeding valve

The safety feeding valve is installed at the feeding port of the powder silo, which can effectively prevent the wrong silo from loading, reduce management costs, ensure the quality of concrete, and prevent production accidents.

  1. Remote display

Remote monitoring shows whether the current silo can be loaded, and guides the vehicle to load the corresponding silo.

Featured Silo Level Sensors

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

Advantages of Radar Silo Level Sensors

High frequency radar Silo Level Sensor is currently the mainstream product for measuring solid level in the world. When measuring solid material level, compared with low frequency radar, high frequency radar has the following advantages:

1) High-frequency radar level gauges (mainly 26GHz and 24GHz) have the advantages of high energy, small beam angle and high precision. However, low-frequency radars have low energy and scattered energy, so all launch angles are large and the directivity is poor. When the diameter of the horn antenna of the low-frequency pulse radar is Φ246, the beam angle is only 15°).

2) The wavelength of 26GHz radar is 11mm, and the wavelength of 6GHz radar is 50mm. When the radar measures the bulk material level, the radar wave reflection mainly comes from the diffuse reflection of the material surface. The intensity of diffuse reflection is proportional to the size of the material and inversely proportional to the wavelength. That is to say, for the same material, the shorter the wavelength is, the easier it is to be reflected, so the echo signal is better during radar measurement. The diameter of most bulk materials is far less than 50mm, which is why 26GHz radar is currently the best choice for bulk material level measurement.

3) Due to the harsh environment on site, dirt, water vapor, etc. will accumulate on the radar antenna over time. The 26GHz radar antenna is small, adding a radome can greatly improve the impact of dirt and water vapor. The 6GHz radar antenna is large, and it is very difficult to add a radome. The overall instrument is large and difficult to clean.

4) When the low-frequency radar (6GHz) measures solids, the measurement range will not exceed 30m. It cannot meet all level measurements of cement lines above 2500T/d scale. The general measurement range of high-frequency radar can reach 70 meters, or even 100 meters. It can fully meet all silos of cement production lines of all scales at present.

5) Because the high-frequency radar level gauge has good directivity and small launch angle. Strong anti-interference ability and so on. It is determined that it is very suitable for the measurement of silos with large aspect ratios. Especially such as calcium carbide furnace material level, converter silo and other material level measurement. Neither of these situations can be measured with low frequency radar.

6) Low frequency radar compared to high frequency radar. Due to its low frequency, the energy is scattered and the energy is not concentrated enough. Therefore, the ability to fight against dust is far inferior to high-frequency radar.

Extended reading: How to Choose the Right Diesel Fuel Level Sensor?

Safe feeding system for powder silo

The remote display of the weighing room shows the warehouse number and the material is allowed to be loaded. The driver holds the card to the ground display terminal and swipes the card if the warehouse allows loading. When the card number is the same as the warehouse number. Only then can the feeding valve be automatically opened.

After the card is valid, the access control baffle is automatically fully opened within 15 seconds. After swiping the card again, the access control shutter will automatically be fully closed within 15 seconds.

The powder safety feeding valve system comes with a closed door detection. Real-time detection of closed door status.

The feeding valve cannot be opened without swiping the card or reading the correct ID information

After loading, the driver needs to swipe his card to close the access control. Then go to the weighing room to hand in the card, otherwise the system prompts that the access control is open. The weighing house will not weigh the vehicle.

At present, the loading port of the cement silo of most mixing plants adopts simple mechanical locking methods. In actual production, it is easy to cause the wrong material to enter the silo, and the loading is not closed and locked. The intelligent material level system for powder silo developed by our company. It has the advantages of easy installation and maintenance, accurate measurement, high safety in use, and no need to stop production during installation. It is currently the preferred solution for real-time measurement of the powder silo level on the market.

Extended reading: 5 Industrial Propane Tank Level Indicators

Solid flow meter | For bulk solids-powder-soybean-cement 

In fact, in addition to monitoring the material level of the bin, we can also know the material level of Silo/Bin by monitoring the flow of solid particles or powder.

What is a solid flow meter?

The solid flow meter is suitable for the measurement of solid mass flow in a wide range of metal-enclosed pipelines from kg/h to t/h. The system is suitable for online monitoring of the flow of solids such as powder, dust, pellets, granules, etc., which are pneumatically conveyed or in free fall (1nm-20mm). Solid flow meters are also called solid powder flow meters, intelligent electrostatic powder flow meters, solid dust flow meters, coal powder flow meters, mineral powder flow meters, lime flow meters, cement flow meters, flour flow meters, petroleum coke powder flow meters.

Read more about: Solid Flow Meter Parameters

More Featured Level Measurement Solutions

FAQ

Simply put, silo levels measurement is divided into contact and non-contact measurement. Technical measures are taken to detect the accumulation height and surface position of granular materials in coal storage bins (raw coal bins, buffer bins, product bins, etc.) in the coal preparation plant. The equipment for detecting the grain position is called the level gauge.

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

The point level sensor can indicate whether the fluid level is higher or lower than a specific point. Usually the point level switch is used as a warning indicator. When the liquid level is too high or too low, an alarm is triggered and the liquid level is kept between two points.

Point level sensors have a wide range of types and are suitable for many applications and materials. The float level sensor is a common point level sensor. The float level switch is composed of a fixed rod and afloat; the float has a built-in permanent magnet that moves freely along the fixed rod as the liquid level rises and falls. The magnetic field of the permanent magnet acts on the reed switch. The closer it is to the reed switch, the stronger the force will be. After the threshold, the reed switch is closed. The float level sensor has a sturdy and durable structure and the measurement deviation is less than 1%.

When every possible intermediate level of a tank or container needs to be measured, a continuous level sensor is required, also known as continuous level measurement. This means that the sensor will provide feedback regardless of the liquid level.
For applications that require continuous level measurement such as fuel tanks and storage tanks, the continuous level sensor can indicate the fluid level in a given container that is within the range.

The radar level sensor is a radar level gauge based on the principle of time domain reflection (TDR). The electromagnetic pulse of the radar level gauge propagates along the steel cable or probe at the speed of light. When encountering the surface of the measured medium. Part of the pulse of the radar level gauge is reflected to form an echo and returns to the pulse transmitter along the same path. The distance between the transmitting device and the surface of the measured medium is proportional to the propagation time of the pulse between them. The height of the liquid level is calculated.

Read more: Non-Contacting Radar Level Measurement


Sino-Inst offers more than 40 powder silo/silo level measurement and control systems. About 50% of them are level gauges and 50% are silo level sensors. Suitable for highest and lowest level product detection, they can be installed in flat bottom silos and hopper silos to prevent silos from overflowing or emptying.

There are various powder silo/silo level measurement and control systems for you to choose, such as free samples, paid samples.

Sino-Inst is a globally recognized powder silo/silo level measurement and control system instrumentation supplier and manufacturer, located in China.

Sino-Inst offers a wide range of high-quality silo level sensors designed for various environments at competitive prices. Helps operators accurately monitor and measure liquid level and flow in silos. A range of non-contact solutions means that the operator does not have to come into direct contact with any substance. It also means that the process is not interrupted.

Sino-Inst’s entire team is well trained, so we can ensure that each customer’s needs are met. If you need any help with your product requirements, whether it is a silo level sensor, level sensors, or other equipment, please give us a call.

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Bidirectional Flow Measurement

What is bidirectional flow?

Bidirectional flow refers to forward and directional flow. Bi-directional flow lines are not common in most process plants. The measurement of unidirectional flow is easy to understand and is applicable to all types of flow technologies. However, most flow technologies cannot accurately measure two-way flow.
They always cause difficulties for process and instrument designers. For two-way flow, the pipeline scheme uses the same pipeline to achieve the transport and/or control function of the opposite flow (forward or reverse flow) according to the process conditions and goals.

Can the flow meter perform bidirectional measurement?

If the flow direction of the medium in the pipeline is reversed. Does the flow meter need to be installed with a flow meter for forwarding use and a flow meter for reverse use accordingly? Is there a flow meter for normal measurement that does not consider the flow direction?

  1. If you just look at the flow rate, you can. For example, an electromagnetic flowmeter. It doesn’t matter if you measure in the whole direction or in the reverse direction. Change the reverse measurement to allow in the prerequisite electromagnetic flowmeter settings.
  2. It’s hard to say if you still need a cumulative amount. How do you convert the cumulative amount you measured forward and the cumulative amount you measured backward? Whether to subtract or add depends on your actual situation.

Extended reading: Insertion Ultrasonic Water Flow Meter – Designed for Agricultural Irrigation, Garden Management

How does the ultrasonic flowmeter realize bidirectional flow measurement?

The principle of the ultrasonic flowmeter is to calculate the fluid flow rate using the difference in sound velocity. And multiply the fluid velocity by the area to calculate the volume flow.

Usually, there is an incident angle between the probe of the ultrasonic flowmeter, that is, the transducer and the meter body. From 60 degrees to 45 degrees. Ultrasonic waves propagate between a pair of probes if there is no fluid, that is, at zero flow. The travel time back and forth is the same. It is equivalent to a zero flow rate.

Extended reading: Ultrasonic Flow Meters Types & Technical Guide

Once there is fluid, the speed of the ultrasonic flowmeter back and forth between a pair of probes is different. Regardless of the direction of fluid flow, there will be a difference in sound velocity. If one direction is set as the normal flow direction, then the normal sound velocity should be a positive number. If the sound velocity difference is negative, the flow is in the opposite direction. That is reverse measurement. The measurement accuracy of the two directions is the same.

Extended Reading: Inline Ultrasonic Flow Meter

Can a vortex flowmeter measure bidirectional flow?

You cannot measure bidirectional flow with just one vortex flowmeter. But in some applications, you can use two for this.

The vortex flowmeter has a bluff body in front of the sensor, which is used to generate the vortex in the flow. As far as I know, no flowmeter has two bluff bodies to measure bidirectional flow.

If you have a two-way steam application. Then you can install two vortex flowmeters in the same line, as long as you respect the inlet and outlet operation of both. However, depending on the size of the line, this setting may become expensive.

Read more General-purpose Flow Totalizer for Data collection and calculation

Bidirectional orifice flowmeter

The bidirectional orifice flowmeter is a differential pressure flowmeter. Mainly used for flow measurement of liquid and gas. According to the characteristics of the orifice flowmeter, it has the advantage of high temperature and high pressure. Therefore, the orifice flowmeter is widely used in the field of high temperature and high-pressure measurement. The orifice flowmeter has high accuracy and good stability and is unanimously recognized by users.

What kind of measurement conditions will use an orifice flowmeter to measure? It can be used according to the requirements of the site, such as typical boiler steam, the general temperature can be close to about 500 degrees, and general flow meters cannot be used. However, the orifice flowmeter can effectively solve this high-temperature working condition, and the only disadvantage is its high cost of use.

Extended reading: 2 inch Water Flow Meter

You may like:

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

Sino-Inst offers over 50 flow meters for flow measurement. About 50% of these are differential pressure flow meters, 40% are the liquid flow sensor, and 20% are Ultrasonic Level Transmitter and mass flow meters.

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

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

What does SCADA stands for?

What does SCADA stand for?

SCADA is the abbreviation of Supervisory Control And Data Acquisition. Namely data acquisition and monitoring control system. SCADA system is also called monitoring configuration software, which is widely used in enterprise equipment management of equipment automatic operation.

What is a SCADA system?

SCADA is a data acquisition and monitoring control system. The scada system is a computer-based production process control and scheduling automation system. It can monitor and control the operating equipment on site. Because each application field has different requirements for scada, the development of scada system in different application fields is not exactly the same.

The scada system is the most widely used in the power system, and the technology development is also the most mature. It is one of the most important subsystems of the energy management system (EMS system). It has the advantages of complete information, improved efficiency, correct control of system operation status, accelerated decision-making, and can help quickly diagnose system fault status. Now it has become an indispensable power dispatcher. Missing tools.

The scada system plays an irreplaceable role in improving the reliability, safety and economic benefits of power grid operation, realizing the automation and modernization of power dispatching, and improving the efficiency and level of dispatching.

How does SCADA work?

The SCADA system deploys multiple software and hardware elements, allowing industrial organizations to: monitor, collect and process data.

Connect and control machines and equipment such as valves, pumps, motors, etc. through HMI (Human Machine Interface) software.

Log the event to a log file.

In the basic SCADA architecture, sensor or manual input information is sent to PLC (Programmable Logic Controller) or RTU (Remote Terminal Unit), and then sent to a computer with SCADA software.

SCADA software analyzes and displays data to help operators and other workers reduce waste and improve the efficiency of the manufacturing process.

An effective SCADA system can greatly save time and money. Many case studies have been published, highlighting the benefits and savings of using modern SCADA software solutions such as ignition.

What is SCADA used for?

The SCADA system has a wide range of applications, and it can be used in the fields of data acquisition, monitoring and control and process control in electric power, metallurgy, petroleum, chemical, gas, railway and other industries. Its functions mainly focus on four aspects: real-time collection of production data, process monitoring of production equipment, abnormal alarms of production equipment, data analysis, data reports and dashboard display. Its characteristics mainly reflect the following aspects.

  1. It supports more than 5000 communication protocols and meets the communication requirements of 99.99% of controllers and instruments on the market. Get through the automated hardware system and the information transmission of the information software system.
  2. Isolate office network IP and industrial equipment IP in hardware to avoid IP conflicts.
  3. Intuitive display of production dynamics, direct or indirect control of on-site equipment, to meet the needs of visual management.
  4. Perform statistical analysis of data and display it through the dashboard.

The SCADA system is centered on the data collected in the production process. It is related to the distribution of people, machines, materials, methods, environments, testing, and R&D. It is based on the data generated during the operation of production equipment. It is also a big Most companies are most concerned about.

Secondly, the SCADA system is aimed at the application needs of the above-mentioned manufacturing enterprises. At the same time, it will give play to its own unique advantages to bring improvements and benefits to the enterprise.

  1. Help companies collect all kinds of data in the production process in real time. Instead of manual operations, it also avoids certain losses caused by personnel errors. Not only improves work efficiency, but also enables real-time monitoring of production All abnormal data in the process provides another layer of guarantee for the quality of the product.
  2. The SCADA system provides the production data of each device, which makes the production situation intuitive and clear, and facilitates the analysis of the production situation by the management personnel of the enterprise, and at the same time helps the enterprise optimize the production, making the production plan more scientific and reasonable.
  3. Realize the digital and intelligent improvement of the management process of products, production schedule, production efficiency, quality information, equipment operation, etc., and optimize the digital management and control capabilities of the production process.
  4. During the company’s external publicity and visit, the company’s image and professionalism will be improved by explaining the application and advantages of the system for the company.

Extended reading: PID Controller Working Principle

The difference between SCADA, DCS and PLC

SCADA and DCS are a concept, and PLC is a product, the three are not comparable:

  1. PLC is a product, which can form SCADA, DCS;
  2. DCS is developed from process control, and PLC is developed from relay-logic control system;
  3. PLC is equipment, DCS and SCADA are systems.

In a narrow sense, DCS is mainly used for process automation. PLC is mainly used for factory automation (production line). SCADA is mainly used for wide-area needs. Such as oil fields, which stretch for thousands of miles of pipelines.

If they are unified from the perspective of computers and networks, the main reason for the differences lies in the application requirements. DCS often requires advanced control algorithms.

For example, in the oil refining industry, PLC requires high processing speed. Because it is often used in interlocking, even fail-safe systems. SCADA also has some special requirements. Such as vibration monitoring, flow calculation, peak and valley adjustment, and so on.

Therefore, you can simply think:

  • SCADA is the dispatch management layer
  • DCS is the plant management
  • PLC is the field device layer

Sino-Inst offers over controllers for Industrial data recording and analysis.

It is widely used in hydropower, tap water, petroleum, chemical, machinery, hydraulic and other industries to measure, display and control the pressure of fluid media on site.

A wide variety of controllers are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of controllers, located in China.

What is Modbus Protocol?

What is meant by Modbus protocol?

Modbus Protocol is a serial communication protocol, which was published by Modicon company (now Schneider Electric) in 1979 for the use of programmable logic controller (PLC) communication. Modbus has become the industry standard (De facto) of communication protocols in the industrial field and is now a common connection method between industrial electronic devices.

Modbus Protocol Features

The main reasons why Modbus is more widely used than other communication protocols are:

  • Published publicly and without copyright requirements
  • Easy to deploy and maintain
  • For suppliers, there are not many restrictions on modifying mobile local bits or bytes

Modbus allows multiple (approximately 240) devices to be connected on the same network to communicate. For example, a device that measures temperature and humidity and sends the results to a computer. In the data acquisition and monitoring control system (SCADA), Modbus is usually used to connect the monitoring computer and the remote terminal control system (RTU).

How does a Modbus work?

Modbus is a master/slave communication mode with a single master station. There can only be one master station on the Modbus network, and the master station has no address on the Modbus network. The address range of the slave station is 0-247, where 0 is the broadcast address. The actual address range of the slave station is 1-247. Modbus communication standard protocol can be transmitted through various transmission methods, such as RS232C, RS485, optical fiber, radio, etc.

Modbus has two serial transmission modes, ASCII and RTU. They define different ways of how data is packaged and decoded. Devices that support Modbus protocol generally support the RTU format. Both communication parties must support one of the above modes at the same time.

The above is the official definition, let’s use ordinary words to explain:

This is actually the communication protocol, and any protocol is similar. There are only two communication formats and communication specifications.

If you want, you can also define a communication specification yourself. Use PLC or VB language to process according to this specification defined by yourself. If the reliability exceeds Modbus, then your communication specification is the most popular!

The difference and connection between RS 485 and MODBUS

I often see RS485 and MODBUS written together, and Sino-Inst will talk to you about the difference and connection between RS485 and MODBUS.

RS485 is a physical interface, which is simply hardware.

MODBUS is an international standard communication protocol used to exchange data between devices of different manufacturers (usually for industrial purposes); the so-called protocol can also be understood as the “language” someone said above, or simply software.

Under normal circumstances, two devices transmit data through the MODBUS protocol: RS232C was first used as the hardware interface, (that is, the serial communication port (serial port) on an ordinary computer). There is also RS422, and there is also commonly used RS485. This interface The transmission distance is long, and it is often used in general industrial scenes.

The MODBUS protocol is divided into three modes: MODBUS RTU, MODBUS ASCII and the later developed MODBUS TCP.

The physical hardware interfaces used by the first two (MODBUS RTU, MODBUS ASCII) are serial (Serial) communication ports (RS232, RS422, RS485).

And MODBUS TCP is to conform to the development trend of the world today. Anything can be connected by Ethernet or Internet to transmit data.

The hardware interface of MODBUS TCP mode is the Ethernet (Ethernet) port, which is the network port generally used on our computer.

We categorize industrial networks into three categories: RS485 network, HART network and fieldbus network.

HART network

HART is a transitional bus standard proposed by Emerson. It mainly superimposes a digital signal on top of a 4-20 mA current signal.

The physical layer uses BELL202 frequency shift keying technology. In order to realize the functions of some smart meters. But this agreement is not a truly open standard, and you have to join his foundation to get the agreement. Part of the cost of joining the foundation.

The technology is mainly monopolized by several large foreign companies, and in the past two years, some domestic companies have started to do it again. But it has not yet reached the level of foreign companies.

Nowadays, a large part of smart meters are equipped with HART round cards and all have HART communication function.

But from the domestic point of view, this part of the function has not been really used, at most it is only used to set the parameters of the handheld communicator. The HART intelligent instrument has not played its due function, and it has not been connected to the Internet for equipment monitoring.

In the long run, due to the low communication rate of HART, the networking is difficult and other reasons. The procurement volume of HART instruments will experience a downward trend.

However, because HART instruments have a history of more than ten years, the number of instruments installed is very large. For some system integrators, there is still a lot of room for use.

Fieldbus network

Fieldbus technology is one of the hotspots of technology development in the field of automation today. Known as the computer local area network in the field of automation. Its appearance marks the beginning of a new era of automation control technology.

Fieldbus is a digital, serial, multi-station communication network that connects the instruments installed in the control site and the control equipment installed in the control room. The key symbol is the ability to support bidirectional, multi-node, bus-style all-digital communication.

In recent years, fieldbus technology has become a hot spot in the development of automation and instrumentation in the world. The appearance of the fieldbus network is a revolutionary change in the traditional control system structure. It is the automatic control system that is moving in the direction of intelligence, digitization, informationization, networking, and decentralization. Form a new type of network integrated fully distributed control system-Fieldbus Control System FCS (Fieldbus Control System).

However, various standards of current fieldbus exist in parallel and have their own areas of survival. There has not yet been a truly unified standard. The key is that we cannot see when a unified standard will be formed, and the technology is not mature enough.

In addition, the types of fieldbus instruments are still relatively small, and the room for selection is small, and the price is relatively high. From the perspective of end users, most of them are still on the sidelines. I want to wait until the technology is mature and consider it, but now there are few implementations.

RS485 network

RS485/MODBUS is a popular way of network layout. Its characteristic is simple and convenient to implement. And now there are many instruments that support RS485, especially in the oil industry.

RS485/MODBUS is simply dominating the world. Current instrument vendors have also switched to support RS485/MODBUS. The reason is simple, like the original HART instrument, it is very difficult and expensive to buy a conversion port. The RS485 conversion interface is much cheaper and has a wide variety.

At least in the low-end market, RS485/MODBUS will still be the most important networking method, and it will not change in the past two to three years.

Features of 4-20mA current loop and RS485 communication (Modbus RTU protocol) data acquisition

4-20mA current loop data acquisition characteristics

Use pressure, temperature transmitter and current acquisition module (RTU) or acquisition card on site for data acquisition and then communicate and transmit with the industrial computer. The data acquisition system using 4-20mA current loop instrument has the following characteristics:

  1. The construction is complicated, data cables need to be buried in advance, the number of cables is large, and the construction period is long
  2. The computer terminal needs a current acquisition card or a data acquisition module
  3. Complicated replacement and maintenance operations, troublesome expansion
  4. 4-20mA current loop data acquisition accuracy is low, and the error comes from 4-20mA output instrument and acquisition card (or data acquisition module)

RS485 communication (Modbus protocol) data acquisition characteristics

Use smart meters, transmitters, actuators, etc. with RS485 communication to directly communicate with the serial port of the industrial computer. The use of RS485 communication digital sensor meter network system has the following characteristics:

  1. The construction complexity is reduced, data cables need to be buried in advance, the number of cables is small, and the construction period is reduced
  2. The computer terminal only needs an isolated RS485/RS232 converter
  3. Easy to replace and maintain, and easy to expand
  4. High acquisition accuracy, eliminating the error of RTU, the system error only comes from the transmitter itself
  5. RS485 communication has good transmission stability and less network maintenance
  6. The cost of use is greatly reduced|
  7. The maximum communication distance of RS485 is 1200 meters

RS485 communication transmission of electromagnetic flowmeter Modbus protocol

The RS485 communication data transmission interface of the electromagnetic flowmeter is half-duplex. The standard rate is greater than 250kHz. The communication direction conversion time is 3.5us. Usually 16-way load can be connected. It can also be expanded to 32 channels. Standard shielded twisted pair cable is 1000m. Use master-slave multi-machine communication. When multiple electromagnetic flowmeters are interconnected. It can save signal lines and facilitate high-speed transmission.

RS-485 communication has good anti-noise interference. Long transmission distance and multi-station capability. Will not affect the synchronization of on-site and remote data due to PLC failure.

However, the electromagnetic flowmeter must have a 485 interface and support the MODBUS RTU protocol.

In order to maintain stability, it is better to use electromagnetic flowmeters of the same manufacturer and the same brand when communicating with multiple flowmeters.

RS485 is a kind of industrial data bus. The electromagnetic flowmeter has RS485 serial communication so that digital communication replaces the transmission of PLC analog signals and ordinary switch signals. The PLC simulation calculation is reduced, and the accurate data collection and transmission are realized.

RS485 precession vortex flowmeter

Precession vortex flowmeter is a new type of gas flowmeter. It can be used for the measurement of natural gas, propane, air, nitrogen and other gases.

The converter can output frequency pulse, 4 ~ 20mA analog signal, and has RS485 interface, can be directly connected to the computer network, transmission distance up to 1.2km;

Precession Vortex Gas Flowmeter, like vortex flowmeter, is a velocity flowmeter. The cost performance of the intelligent precession vortex flowmeter is higher than vortex flowmeter. The intelligent precession vortex flowmeter can only measure gas. Precession Vortex Gas Flowmeter can be made into an integrated temperature and pressure compensation. And can measure various gases. Such as compressed air, oxygen, biogas, natural gas, coal gas, etc.

Read more about Everything You Need To Know About Electronic Flow Meters