Contact and Non-contact | Capacitive water level sensor

A capacitive water level sensor is often used to measure the water level of the water storage tank. The capacitive water level sensor uses the change of measuring capacitance value to measure the height of the liquid level. The main function is to continuously measure the liquid level of the measured medium liquid. For example, common media are sewage, mud, paper pulp, eight-treasure porridge, and so on. You may also have heard of a non contact capacitive water level sensor. It is a kind of capacitive water level sensor installed externally.

 Capacitive water level sensor

What is a capacitive liquid level sensor?

The Capacitive liquid level sensor is based on the principle of capacitance sensing. When the height of the measured electrode is changed by the measured medium, it will cause its capacitance to change. It can convert the changes of various material levels and the height of liquid level media into standard current signals, which are remotely transmitted to the operation control room for centralized display, alarm or automatic control by secondary instruments or computer devices.

Capacitive liquid level sensor has a good structure and installation method, which can be applied to high temperature, high pressure, strong corrosion, easy to crystallize, anti-clogging. Anti-freezing and solid powdery and granular materials.

The Capacitive liquid level sensor fundamentally deals with the influence of factors such as temperature, humidity, pressure, and material conductivity on the measurement process. Therefore, it has extremely high anti-interference and reliability. It can measure strong corrosive liquids, such as acid, alkali, salt, sewage, etc.

Can measure high temperature and high pressure medium. Process temperature -40~600℃. Process pressure -0.1~4.0MPa.

A single intelligent integrated capacitance level gauge has common two-point on-site calibration skills, which provides convenience for users to easily use the product.

Capacitive liquid level sensor can measure the liquid level of strongly corrosive medium, measure the liquid level of high temperature medium, measure the liquid level of sealed container. It has nothing to do with the viscosity, density and working pressure of the medium.

Extended reading: Ultrasonic liquid level sensors

Capacitive water level sensor

Can capacitive liquid level sensors measure water?

OK. Because water is conductive. Except for pure water, ultra-pure water, industrial water has no special instructions, it is generally regarded as a conductor.

Capacitive water level sensor is when measuring water. The water contains rust, jelly, etc. Will it cause measurement fluctuations?

probably not. When measuring water, there are two plates: one is the metal rod of the capacitor itself. And the other is actually water. Because general water is conductive. The dielectric is actually the film on the outside of the Capacitive water level sensor metal.

  1. When the tank is a conductor: because water is conductive. Except for pure water, ultrapure water, industrial water without special instructions is generally regarded as a conductor. So it forms the other plate of the capacitor. When the metal tank is used to measure the conductor level with a capacitor, the dielectric is the layer of PTFE.
  2. If the tank body and process connection are non-conductive materials. Then, a conductor should be led down from the ground terminal of the meter casing along the outside of the tank as another plate. The dielectric at this time is membrane + medium + tank wall.

Non contact capacitive water level sensor

Non contact capacitive water level sensor, you only need to attach the sensor to the outer wall of the container made of insulating material when using it.

When the liquid level reaches the sensor detection position, there is a level signal output. It is easy to install and use, no need to open holes, and durable life. Capacitive type can detect the liquid level through the medium. No direct contact with liquid is required. It will not be affected by corrosive effects such as strong acids and alkalis, and it is more hygienic.

Extended reading: Radar Non Contact Water Level Sensor

Features of Non contact capacitive water level sensor:

  1. Small size and high cost performance. Waterproof grade IP62. Ultra low standby function
  2. The liquid level can be detected through the medium without direct contact with the liquid. It will not be affected by corrosive effects such as strong acids and alkalis, and it is more hygienic.
  3. No need to open holes without mechanical parts inside. Only need to be installed on the outer wall of the container to achieve non-contact use
  4. Integrated filtering, debounce, and A/D conversion circuit. Directly output high and low levels.
  5. Accuracy, high reliability, no virtual area, no gray sensing area
  6. Meet the requirements of safety standards
  7. Comply with RoHS requirements
  8. The sensitivity can be matched according to the customer’s application

Non contact capacitive water level sensor application:
It can be used to detect water purification, sewage, oil, wine, various acid-alkaline liquid levels, etc. Mainly suitable for household appliances, medical equipment, chemical equipment, business machines, etc. Your equipment needs level control. Our products will meet your liquid level measurement needs.

Extended reading: Ultrasonic level transmitter for Hazardous Liquids

Compared with non contact capacitive water level sensor and float type liquid level sensor:

  1. It can be used when installed on the outer wall of the container, and the container does not need to be opened. The water level can be detected non-contact.
  2. Small size, small space required for installation
  3. The float type liquid level sensor needs to be in contact with the liquid to detect the liquid level. The internal magnet will adsorb impurities in the water to form scale. Scale will cause the weight of the float to increase and affect the accuracy of liquid level detection. The Non contact capacitive water level sensor does not directly contact the liquid, and there is no such restriction.
  4. The float type liquid level sensor uses the rise and fall of the liquid level to drive the movement of the float with a magnet. So that the internal dry reed switch is turned on and off. Therefore, the float type liquid level sensor has a certain draft, the float is easy to jam, and the reliability is low. The Non contact capacitive water level sensor has no mechanical moving parts and has high reliability.

SI-U01 Float Level Sensor
SI-U02 Multi-Point Liquid Level Float Switch
SI-U03 Float Switch Water Level Controller
SI-U04 Magnetic Float Level Sensor-Reed Switch
SI-U05 Cable Float Level Sensor & Swtich

Frequently
Asked
Questions

  1. Under stable working conditions, due to structural limitations, the compensation problem of system measurement errors caused by the adiabatic temperature of the water side cannot be completely solved. Under accident conditions such as boiler shortage or full water, excessive system measurement errors may bring serious consequences
  2. The structure is complex, and there are many static sealing points. The scale of construction is large and there are problems of heat preservation in winter.
  3. The measurement time lag is long, and the boiler water level change cannot be reflected immediately. The quality of the measurement signal adjustment is poor.
  4. Due to the exothermic heat of the condensing cylinder, the use cost is extremely high.

Extended reading: Amazing Solutions for Continuous Liquid Level Measurement

The capacitance level switch determines whether there is liquid by detecting the conductivity or insulation rate of the medium. It can be simply understood as judging whether the liquid has reached a fixed water level according to the size of the capacitance value. The capacitor is formed between the liquid level switch and the medium in which it is located. When liquid is detected, the capacitance value changes greatly.

Extended reading: Radar Level Sensor Working Principle

More Water level sensors

Water depth sensors are also known as water level sensors. Water depth sensors are often used to measure tank levels, well depths, river depths, etc. There are many different types of water depth sensors. All of them are used to measure the water level by submerging underwater or above the water surface. Then, they are converted into a water depth or water level signal. For example, submersible hydrostatic level meter, ultrasonic level meter, etc.

Extended reading: Non contact level measurement

Sino-Inst offers over 20 Capacitive water level sensors for level measurement.

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

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

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

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Food Grade Flow Meters for Food & Beverage Industry

In the food and beverage industry, automation equipment requires food grade. Ensure hygiene and safety. The food grade flow meter can easily sterilize the equipment without disassembly. Many of the flowmeters we provide use accessories such as triple clamps, clover, and 3A pipe fittings. These fittings are sanitary food-grade fittings for stainless steel clamp pipe joints.

Flow measurement in the food industry

In the food and beverage processing industry, accurate measurement and control of raw materials are very demanding. Food grade flow meters Cut costs and increase productivity. Certain processes in the food industry require sanitary conditions. Food industry: dairy products, alcohol, beverages, syrup, chocolate, edible oil, etc.

Food grade oil flow meter

Food grade flow meters can measure edible oil.

There are many steps in the processing of edible oil that require a flow meter to measure the volume and weight of how much oil flows out of the pipeline. Companies that produce and process edible oils need to use flow meters for statistics on the crude oil that is initially refined and the essential oil that is finally refined.

First of all, for oil measurement, electromagnetic flowmeters cannot be selected.

You can choose turbine flowmeters, gear flowmeters, ultrasonic flowmeters, metal rotor flowmeters to measure oil. If you need high-precision measurement. You can also consider mass flow meters.

Extended reading: Sanitary Positive Displacement Flow Meter

Flowmeter used in the beverage industry

An electromagnetic flowmeter is used to measure the volume flow of conductive liquid medium with conductivity greater than 5μs/cm. Electromagnetic flowmeters are usually used to measure the flow of large pipelines. It can be accurately measured in a large beverage production workshop. The minimum diameter of the current electromagnetic flowmeter is 0.1 inches, that is, 2.5 mm, and the maximum diameter can reach nearly 3 meters.

The beverage industry includes beer, fruit juice, etc., and electromagnetic flowmeters could not be better. Generally, the medium is conductive, and it is very good to add ions appropriately. And there is no loss. There is no differential pressure loss or something.

Originally, there are still many ways to protect the electrodes of the electromagnetic flowmeter. We should pay more attention to it in the process of use. Don’t cause the electromagnetic flowmeter to fail to operate normally in the future due to a little negligence.

Flow measurement in Breweries

What kind of flowmeter can be used to solve beer flow measurement? Beer is a conductive medium. Can use electromagnetic flowmeter to measure. When measuring beer, you only need to use stainless steel electrodes and tetrafluoroethylene lining. The electromagnetic flowmeter is a measuring instrument with high measurement accuracy and good stability. It has been widely used in beer flow measurement.

Beer flow measurement. Let’s take a look at how to select a beer electromagnetic flowmeter:

  1. Medium
  2. Temperature
  3. Pressure

When measuring beer flow, you can select according to the above three corresponding parameters to meet the on-site measurement requirements.

Of course, except for electromagnetic flowmeters. The sanitary turbine flowmeter can also be used to measure beer or liquor.

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

Syrup flow measurement

Food grade flow meters can measure syrup.

High viscosity syrup flow measurement

If the viscosity of the measured syrup is relatively high. Then I recommend using a target flowmeter or an oval gear flowmeter.

The target flow meter is a speed meter. It calculates the flow rate of the medium according to the force of the medium pushing the target. Its intelligent liquid crystal meter head can clearly display the instantaneous flow and cumulative flow of the medium. And output 4-20mA signal. The installation is simple and the maintenance is small. High temperature and high-pressure resistance. Suitable for large, medium, and small pipe diameters. The application range is very wide.

The oval gear flowmeter is a positive displacement flowmeter. It is a mechanical instrument. He calculates the medium flow rate based on the measurement of the rotation of the internal gear. The general configuration is a pointer display type, which only displays the cumulative flow and does not display the instantaneous flow. Therefore, the user needs to explain to the manufacturer when displaying the instantaneous flow rate. The manufacturer will be equipped with a smart meter.

In addition, the output signal is a pulse signal. The user needs a 4-20 mA signal, and the manufacturer also needs to explain it to the manufacturer. Oval gears are relatively bulky. Therefore, it is not suitable for the measurement of large-diameter pipes. Its largest caliber is also smart to 200mm.

Why Generally Choose 4-20ma Output?

In addition to the above two types of vortex, flowmeters are also possible.

Low viscosity syrup flow measurement

If the measured viscosity of the syrup is not very high, an electromagnetic flowmeter or a liquid turbine flowmeter has been used.

Electromagnetic flowmeters are mainly used for the measurement of medicines such as glucose syrup and food syrup. Because medicine and food have higher hygiene requirements. Strict disinfection is required, so clamp-type electromagnetic flowmeters are generally used.

The liquid turbine flowmeter measures low viscosity, and the effect of relatively pure syrup is very good. Responsive, high precision, beautiful and light appearance, installation and maintenance are also very simple. It is suitable for the measurement of small and medium pipelines. Both types of flow meters are smart meters. On-site LCD displays instantaneous flow and cumulative flow. Output 4-20mA signal. The scope of application is also very wide.

Here I simply recommend several flow meters based on the viscosity of the syrup. How to choose specifically. Users need to provide relevant parameters and requirements to make the most suitable and correct choice.

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

Featured Food grade flow meters

Food grade positive displacement flow meter

Positive displacement flow meters, also known as fixed displacement flow meters or PD flow meters, are the most accurate measuring instruments. The oval gear flowmeter is the most typical positive displacement flowmeter.

According to the measuring elements, the volumetric flow plan can be divided into elliptical gear flow meters, double rotor flow meters, disc flow meters, rotary piston flow meters, wet gas meters, and membrane gas meters, etc. The clamp connection oval gear flowmeter has the advantages of a lightweight and convenient connection. Especially in the chemical and pharmaceutical industries, it has a wide range of uses.

Extended reading: Mechanical flow meter types

FAQ

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.

Extended Reading: Insertion Flowmeter Types

The price of a flowmeter is determined by the type and parameters of the flowmeter.

Important factors when selecting flow metering devices are

  • accuracy
  • cost
  • legal constraints
  • flow rate range
  • head loss
  • operating requirements
  • maintenance
  • lifetime

These factors are more or less related to each other. For example – the cost of flow meters increases with accuracy and lifetime quality.


Water flow meters are flow meters that can display the flow rate of industrial water pipes.

A water flow meter measures the amount of water flowing through a pipe. We have several kinds to choose from, depending on the application, maintenance needs, and budget.

There are four common water flow meter types:

Turbine (also called mechanical), Vortex, Ultrasonic, and Magnetic. We will tell you everything you need to know about them and help you choose one for your application.

Extended reading: Ultrasonic Flow Meters Types & Technical Guide

Different manufacturers and different models have different accuracy levels.
The accuracy of general flow meters is divided into 0.1, 0.2, 0.5, 1.
Mass flow meters can reach even higher accuracy levels.
Common flow meters can achieve 1 or 0.5.

Extended reading: Gas Rotameter Tips

Extended reading: Metal Tube Flow Meter-Variable Area Flow Meters Principle

In general, the principle of selecting a flow meter is to first have a deep understanding of the structural principles and fluid characteristics of various flow meters. At the same time, the selection should be made according to the specific situation of the site and the surrounding environmental conditions. Economic factors must also be taken into consideration.

In general, you should choose from the following five aspects:

  • The performance requirements of the flowmeter;
  • Fluid characteristics
  • Installation requirements;
  • Environmental conditions
  • The price of the flow meter.

Read more about: Coriolis meter for High viscosity liquid

Still have questions?

If you cannot find an answer to your question in our FAQ, you can always contact us
and we will be with you shortly.

Sino-Inst offers over 10 Food grade flow meters, with the Best Price. Food grade flow meters are Also called sanitary flowmeters.

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

About 13% of these are magnetic flow meter, 14% are Turbine Flow Meters, 25% are Venturi flow meter, 13% are Handheld ultrasonic flow meter, and others are Liquid mass Flow Meters.

Sino-Inst is Food grade flow meters supplier, located in China. Food grade flow meters products are most popular in North America, Mid East, and Eastern Europe. The United States, and India, which export 99%, 1%, and 1% of Food grade flow meters respectively.

Gas Rotameter Tips

What is Gas Rotameter?

Rotameter is also called float flowmeter. It is often called glass tube float flowmeter, glass rotameter, metal rotameter, and metal tube float flowmeter.
Rotameter is mainly used to measure the flow of single-phase non-pulsating fluid (gas or liquid). When gas or liquid is introduced into a uniform conical flow tube. The float rises. Its weight is supported by the fluid flowing below. Until the entire fluid volume is available Flow through the float. The position of the float corresponds to a point on the pipe measurement scale and provides an indication of the fluid flow rate.

Can rotameter be used for gases?

Rotameter can measure gas.

Rotameter is a variable area flow measuring instrument commonly used in industrial automation process control, which can be used to measure the flow of liquid, gas, and steam.

Rotameters are especially suitable for dry gas and steam measurement. Such as the measurement of nitrogen, air, oxygen and other gases.

It is not applicable if the liquid medium or gas medium contains impurity particles. It will affect the accuracy of the measurement.

If the pressure is relatively large, you can use a metal tube float flowmeter. The metal tube float flowmeter can transmit signals remotely for total accumulation or flow control. You can also customize the remote metal rotor flowmeter according to your needs. Explosion-proof metal rotor flowmeter.

Further reading: Nitrogen(N2) Flow Meter Types

More Featured Gas meters:

Extended reading: Beginner’s Guide: Variable area flow meter

Air Rotameter

Metal tube rotameter can be used to measure air. Because the rotameter is a variable area flow measuring instrument commonly used in industrial process automation control.

Rotameter has the characteristics of small size, large detection range and convenient use. It can be used to measure the flow of liquid, gas and steam. It is especially suitable for medium flow measurement with low flow velocity and small flow. Therefore, there is no problem in measuring air. However, it should be noted that the metal tube rotor flowmeter is only suitable for the flow measurement of small-diameter and low-velocity media within DN200.

Extended Reading: Digital air flow meters

Rotameter is a variable area flow measuring instrument commonly used in industrial automation process control. It is mainly to measure the instantaneous flow of various liquid gases and steam under different working conditions. You can directly observe the value under the flow state of the medium. It can easily solve the problem of fluid flow measurement under various working conditions.

The metal rotor flowmeter has the characteristics of simple structure, large detection range, high temperature and high-pressure resistance, anti-corrosion, and explosion-proof. It has a wide range of applications in petroleum, chemical, metallurgy, electric power, medicine, food, sewage treatment, and other industries.

Read More about: Digital Rotameter

The common accuracy of the rotameter is 1.5. This accuracy has been able to meet the measurement needs of most users.

Extended reading: Buy Digital Gas Flow Meters & Controllers For Air-O2-N2-CO2

Yes. Rotameter can Be Used for Gases.

Rotameter is the most widely used variable area flowmeter type. Rotameters are called gravity flowmeters because they are based on the opposition between the downward force of gravity and the upward force of the flowing fluid.

When the flow is constant, the float stays at a position related to the volume flow. The position is indicated by a scale. Please note that in order to maintain the full effect of gravity, this dynamic balancing action requires a vertical measuring tube.

Other forms of gravity meters may include a piston or vane that responds to flow in a manner similar to the behavior of a float. All these devices can be used to measure the flow of most liquids, gases, and steam.

There are similar types that use springs instead of gravity to balance fluid flow. These do not need to be installed vertically, but corrosive or aggressive fluids can damage the spring and cause reduced accuracy.

Extended Reading: What is difference between rotameter and flow meter

Rotameters are generally divided into three categories: plastic rotameters, glass rotameters and metal rotameters according to the material of the tapered tube.

  • The former two are generally in-situ indicating type, and the latter is generally made into a flow transmitter.
  • According to different converters, metal rotor flowmeters can be divided into gas remote transmission, electrical remote transmission, indication type, alarm type, and integrated calculation.
  • According to the structure and purpose of the transmitter, it can be divided into basic type, jacket insulation type, anti-corrosion type, high temperature type, high pressure type and so on.

Extended reading: What is an air pressure transducer?

More about Types Of Air Flow Measurement Instruments.

Chlorine Gas Rotameter

Rotameters are used to measure the flow of various small-diameter media. Of course, it is also very reliable when used in the chlorine flow measurement industry.

For the measurement of chlorine gas, the metal tube rotameter can fully meet this measurement requirement. Rotameters are not only made of metal, but also made of glass.

Comparing the two, the metal tube rotor flowmeter has on-site display and intelligent remote transmission functions. The measurement accuracy is high and it is easy to use. And the whole is relatively sturdy and has a long service life.

The glass tube rotameter has a simple structure. There should be no bumps during use. It is fragile and non-explosive, and has a short service life. The metal tube rotameter is superior to the glass tube rotameter when measuring chlorine.

Extended reading: Gas Mass Flow Meter

The flow meters that can be used to measure chlorine are: rotameter, vortex flowmeter, differential pressure flowmeter, gas mass flowmeter, etc. Since chlorine is very corrosive, especially when there is moisture, it is necessary to consider anti-corrosion treatment.

Nitrogen Gas Rotameter

There are many types of Nitrogen gas flow meters. There are three types of flow meters commonly used to measure nitrogen. Precession vortex flowmeter, gas vortex flowmeter, thermal gas mass flowmeter. When selecting a model, it is necessary to select a suitable model and specification according to the parameters and cost that can be provided on-site.

Of course, the rotameter is also a good choice for measuring nitrogen. Because of the low cost.

Read more anout: Nitrogen Gas-Liquid Nitrogen Flowmeters

Hydrogen Gas Rotameter

There are three types of flowmeters commonly used to measure hydrogen flow: precession vortex flowmeter, gas vortex flowmeter, and thermal gas mass flowmeter. When selecting a model, it is necessary to select a suitable model and specification according to the parameters and cost that can be provided on site. You must communicate well with the sales staff to make the measurement accurate.

Of course, the rotameter is also a good choice for hydrogen measurement. Because of the low cost.

Extended reading: Featured Hydrogen flow meters

Natural Gas Rotameter

The flow measurement of natural gas is currently mainly used in trade settlement and is relatively common. my country’s natural gas trade measurement is based on the volume or energy method under the legally required quality indicators for transfer measurement. At this stage, volume measurement is basically the main method.

At present, the flowmeter products used for natural gas flow measurement generally include: gas waist wheel flowmeter, gas turbine flowmeter, precession vortex flowmeter, vortex flowmeter, ultrasonic flowmeter and orifice flowmeter.

Let’s make a simple comparison on the use of these flow meters.

Extended reading: 5 matters to pay attention to when choosing threaded Vortex Nitrogen Gas Flow Meter

Rotameter Gas Flow Conversion

When measuring gas and liquid media, are the parameters of the rotameter the same?

Metal rotor flowmeter is a variable area flow measuring instrument commonly used in industrial automation process control. When it is measuring liquid and gaseous media, because the density of the two media is different, the material of the rotor of the flowmeter will also be different due to the density of the medium.

Regardless of whether it is measuring gas or liquid, the metal rotor flowmeter is the same in appearance and structure. But because the density of a gas is lower than that of liquid, the density of gas rotor material is smaller than that of the liquid rotor.

Whether the rotameter for measuring gas or liquid, the structure is basically the same, and it is equipped with a rotor in a conical tube. The main differences are as follows:

  1. The calculated density of the rotor: the density for liquid is high, and the density for gas is low.
  2. Rotor shape: the cross-sectional area of ​​liquid is relatively small, and the cross-sectional area of ​​gas is relatively large
  3. Damping device: It is better to use a damping device for liquids and gas, so that the measured value is stable.

Therefore, when we choose the metal rotor flowmeter, we need to clearly describe the real-time conditions of the working conditions with the manufacturer. In this way, we can formulate qualified process and technical parameter models of flowmeters according to the actual requirements of the working conditions. So as to be able to solve the measurement problem more effectively.

Extended reading: Radar level sensor for solids – Dust solid level measurement

Gas Rotameter Calibration

It is not feasible to calibrate metal tube rotameters with conventional methods. This is determined by the structural principle of the transmitter.
Because the rotameter is between the input pressure source and the generated 4-20mA current signal. Besides to machinery and circuits. There are also micro-processing chips that perform calculations on input data. Therefore, the adjustment is different from the conventional method.

In fact, the manufacturer also has instructions on the calibration of metal tube rotameters. A series of transmitters produced by our company. For calibration, there are: “Set range”, “Re-quantity range”, “Fine adjustment” points.

Extended reading: liquid nitrogen level measurement

Among them, the “set range” operation is mainly to complete the configuration work through the number of LRV and URV. The “re-quantity range” operation requires the transmitter to be connected to a standard pressure source. Guided by a series of instructions, the transmitter directly senses the actual pressure and sets the value. The initial and final settings of the range directly depend on the actual pressure input value. But it should be seen that although the analog output of the transmitter has a correct relationship with the input value used. But, the value displayed by the digital readout of the process value will be slightly different. This can be calibrated by fine-tuning items.

Because each part of the metal tube rotor flowmeter needs to be adjusted separately and must be adjusted together. Therefore, the actual calibration can be carried out according to the following steps:

Make a 4-20mA fine-tuning first. It is used to calibrate the D/A converter inside the transmitter. Because it does not involve sensing components.

No external pressure signal source is required.

Do one more full fine-tuning. Make the 4-20mA and digital readings coincide with the actual applied pressure signal. Therefore, a pressure signal source is required.

Finally, do the re-quantification process. Adjust the analog output 4-20mA to match the external pressure signal source. Its function is exactly the same as that of the zero adjustment (Z) and range adjustment (R) switches on the transmitter housing.

Some people think that the range of metal tube rotameter can be changed as long as the HART handheld communicator is used. And can adjust the zero point and span. There is no need to enter a pressure source. But this approach cannot be called calibration, but can only be called “setting range”.

The real calibration requires a standard pressure source to enter the transmitter. The range adjustment (LRV, URV) is not calibration because the standard instrument is not used. Ignore the input part (pressure of the input transmitter) to adjust the output, (transmitter conversion circuit) is not a correct calibration.

Furthermore. The relationship between pressure and differential pressure detection components. A/D conversion circuit. And current output is not equal. The purpose of calibration is to find out the relationship between the three changes.

Extended reading: Cryogenic Flow Meters | Liquid Nitrogen-Liquid Oxygen

Extended reading: How does a rotameter work

Sino-Inst offers over 30 rotameter products. About 50% of these are for liquids. 40% are for gas. At the best price.

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

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

The top supplying country is China (Mainland), which supply 100% of the Float Flow Meter respectively.

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

Float Flow Meter Technology

What is a float flow meter?

The float flow meter is also called a rotameter. The float flow meter is a volumetric flow meter in which a float rises and falls in a vertical tapered tube as the flow changes, changing the flow area between them. It is often called Variable Area Flowmeter or Area Flowmeter in the United States and Japan. The float flow meter can be used to measure the flow of liquid, gas, and steam. It is especially suitable for medium flow measurement under low flow rates and small flow conditions.

How does a float flow meter work?

Float Flow Meter is also called rotor flow meter. It is mainly used for small and medium caliber flow measurement. It can measure liquid, gas, steam, etc. The product series have complete specifications and are widely used.

Extended reading: Gas Rotameter Tips

Float Flow Meter working principle

Float Flow Meter consists of two parts. One of the rotameter is a tapered tube that gradually expands from bottom to top. The other is a rotor that is placed in the tapered tube and can move freely up and down along the centerline of the tube.

When measuring the flow of fluid, the measured fluid flows in from the lower end of the tapered tube. The flow of fluid impacts the rotor and produces a force on it. The magnitude of this force varies with the flow rate.

When the flow is large enough, the generated force will lift the rotor and raise it.

Extended reading: Fluid flow meter types

At the same time, the measured fluid flows through the annular section between the rotor and the tapered tube wall. At this time, there are three forces acting on the rotor. The dynamic pressure of the fluid on the rotor, the buoyancy of the rotor in the fluid, and the gravity of the rotor itself.

When the flowmeter is installed vertically, the center of gravity of the rotor coincides with the axis of the tapered tube. The three forces acting on the rotor are all along the direction parallel to the axis of the tube.

When these three forces reach a balance, the rotor floats smoothly on a certain position in the cone tube.

For a given rotameter, the size and shape of the rotor have been determined. Therefore, its buoyancy in the fluid and its own gravity is known to be constant. Only the dynamic pressure of the fluid on the float changes with the flow rate of the incoming flow.

Therefore, when the flow rate of the incoming flow becomes larger or smaller, the rotor will move up or down. The flow cross-sectional area of ​​the corresponding position also changes. Until the flow rate becomes the corresponding speed when the flow rate becomes balanced, the rotor is stable in the new position.

For a given rotameter, the position of the rotor in the cone tube is in one-to-one correspondence with the flow rate of the fluid flowing through the cone tube.

In order to prevent the rotor from touching the tube wall when moving up and down on the centerline of the tapered tube, two methods are usually used.

One is to install a guide mandrel in the center of the rotor to keep the rotor moving up and down on the centerline of the tapered tube.

The other is a chute on the edge of the rotor disc. When the fluid flows through the rotor from bottom to top, one side bypasses the rotor. At the same time, it passes through the chute to generate a reverse thrust. The rotor keeps rotating around the centerline. . It can keep the rotor from touching the pipe wall when working. The rotor material of the rotameter can be made of stainless steel, aluminum, bronze, etc.

Extended reading: Micro flow meters for low flow liquids

Types of Float Flow Meter-variable area flowmeter

It can be divided into transparent material cone tubes and metal cone tubes.

  1. Transparent conical tube float flow meter

Transparent tapered tube materials include glass tubes, transparent engineering plastics such as polystyrene, polycarbonate, plexiglass, etc. Among them, glass pipes are most used, but they are easy to break. Engineering plastic pipes are not easy to break. Some are also resistant to corrosion by corrosive media such as acid and alkali.

The diameter of the transparent tapered tube float flow meter is 15~40mm, and the flow index is directly engraved on the outer wall of the tapered tube. Or an indexing scale is installed beside the tapered tube. The tapered tube has a cone smooth surface and a guiding rib (or flat surface). ) Two kinds.

The float moves freely in the tapered tube or moves under the guidance of the tapered tube ribs. The instrument on the inner wall of the large smooth surface is also guided by a guide rod.

Extended Reading: What is difference between rotameter and flow meter

  1. Metal Conical Tube Float Flow meter

The diameter of the metal tube conical tube float flow meter is 15~40mm, and the displacement of the float is transmitted to the conversion part outside the casing by means of magnetic steel coupling. Compared with transparent conical tube float flow meter. It can be used for higher medium temperature and pressure. And it is not easy to break.

Extended reading: Metal Tube Flow Meter-Variable Area Flow Meters Principle

There are several other structures of the transparent float flow meter. For example, the transparent straight tube float flowmeter is a deformed structure of the transparent conical tube float flow meter. The flow detection element is composed of an orifice plate and a cone floating plug.

There are other types of deformed structures of the metal tube conical tube float flowmeter. Among them, the direct indication type directly observes and reads the position of the float through the transparent straight pipe and the floating plug.

The horizontal installation type can be installed in the horizontal pipeline; the straight-through type has a different right-angle flow direction from the typical structure. It is not necessary to change the flow direction. It can be directly connected to the vertical pipeline. Easy to install.

The floating plug orifice plate type replaces the rotor tapered tube with a floating plug orifice plate. It is more convenient to change the flow specification as long as the floating plug with a different taper is changed.

Extended Reading: Magnetic Battery Operated Flow Meter

It can be divided into on-site instructions, pneumatic remote signal output, electric remote signal output, alarm, etc. Transparent tube float flowmeters are all on-site indication types.

Sometimes a proximity switch is installed to output upper and lower limit alarm signals.

The conversion part of the remote signal output instrument converts the displacement of the float into an analog signal output of current or air pressure. Respectively become air remote transfer float flowmeter and electric remote transfer float flowmeter.

Read More about: Digital Rotameter

It can be divided into hose connection, flange connection, and threaded connection.

There are three connection methods for the transparent tube float flowmeter.

Among them, hose connection is often used for instruments with a diameter of less than 10mm and places with low working pressure.

The threaded connection is often used for instruments with a diameter below 40mm. The scope of application is not wide.

Flange connection is used for instruments with a diameter of 15~100mm, and the application is the most common.

Metal tube float flowmeters are usually flanged, and individual models are connected by a thread.

It can be divided into liquid, gas, and steam.

Most float flow meters can measure both liquid and gas in the same instrument.

Only specially designed metal tube float flowmeters can be used to measure steam. Or add additional components to the standard instrument. Such as adding liquid damping parts with fins. Install heat sinks at the junction with the indicating conversion part.

Extended Reading: Insertion Flowmeter Types

It can be divided into basic types, jacket insulation types, explosion-proof types, corrosion-resistant types, and blowing types. The basic type is the most widely used.

Jacket insulation type is used for occasions where the temperature in the pipeline is significantly higher (or lower) than the ambient temperature.

When used in explosive gas or dust, the electric remote float flowmeter adopts an explosion-proof type. At present, there are explosion-proof design structures and intrinsically safe explosion-proof design structures in China.

Corrosion-resistant float flowmeters are made of engineering plastics such as polytetrafluoroethylene, etc., for the structural parts and float in contact with the medium.

The flow rate of the blowing type is small, the air is 20~3000L/h, and the water is 0.3~100L/h, and the accuracy requirements are not high.

The blow-flow type float flowmeter is integrated with a small self-operated differential pressure regulator. The flow change is caused by the pressure fluctuation of the power source or the disturbance of the downstream parameter change. Self-adjustment to maintain a constant flow rate.

It can be divided into full flow type and split flow type.

The full-flow type refers to the instrument in which all the fluid to be measured flows through the float flowmeter.

The shunt type means that only part of the measured fluid flows through the flow detection part such as the float. The shunt-type float flowmeter is a combination of a standard orifice plate installed on the main pipe and a smaller diameter float flowmeter. It is used for larger flow rates with pipe diameters greater than 50mm. And as long as the place indicated on the spot.

Float type water flow meter

Rotameters can be used to measure the instantaneous flow of water. There are many flow meters for measuring water. Almost all flow meters that measure liquids can be used to measure water.

The original rotameter used to measure water is now used to measure the flow rate of gasoline. Is the reading correct?

Certainly not. Rotameter measuring liquid is most affected by liquid density and viscosity. It is recommended to find the manufacturer to tell them the parameters of your gasoline. It should be able to help you convert and tell you the true flow rate when the current scale is used to measure gasoline.

Rotameters measure different liquids. How to convert?

Rotameter display value correction. The fluid and state when the flowmeter is in use are generally different from the fluid and state when the flowmeter is scaled. Therefore, the value of the flow meter reading during use is not the real flow through the flow meter. The indicated value must be corrected according to the fluid and state in use. In order to get the correct flow.

The flow meter produced by Sino-Inst is calibrated with water for measuring liquid. The flowmeter for measuring gas is calibrated with air. The indicated value is scaled according to the volume flow rate of the standard state (water at 20°C; air at 20°C, 101.325KPa). Therefore, all corrections are based on the standard state index.

Extended reading: Beginner’s Guide: Variable area flow meter

More Featured Water Flow Meters:

Float air flow meter

Metal tube rotameter can be used to measure air. Because rotameter is a kind of variable area flow measuring instrument commonly used in industrial process automation control.

It has the characteristics of small size, large detection range, and convenient use.

It can be used to measure the flow of liquid, gas and steam. It is especially suitable for medium flow measurement with low flow rate and small flow, so there is no problem in measuring air.

However, it should be noted that the metal tube rotor flowmeter is only suitable for the flow measurement of small-diameter and low-velocity media within DN200.

More Featured air flow meters:

Frequently
Asked
Questions

Rotameter is a kind of variable area flowmeter. The working principle of the rotameter is in a vertical cone tube that expands from bottom to top. The gravity of the float of the circular cross-section is borne by the hydrodynamic force. The float can be in the cone The tube rises and falls freely. It moves up and down under the action of flow velocity and buoyancy. After being balanced with the weight of the float, it is transmitted to the dial to indicate the flow through the magnetic coupling.

The rotameter consists of two parts. One of the rotameter is a tapered tube that gradually expands from bottom to top. The other is a rotor that is placed in the tapered tube and can move freely up and down along the centerline of the tube.

When measuring the flow of fluid, the measured fluid flows in from the lower end of the conical tube. The flow of fluid impacts the rotor and produces a force on it. The magnitude of this force varies with the flow rate). When the flow rate is large enough At this time, the force generated will hold up the rotor and raise it.

The accuracy of the conventional model of the rotameter is 1.5. This accuracy is not the highest. But it has been able to meet the measurement needs of most users.

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

Sino-Inst offers over 30 Float Flow Meter products. About 50% of these are for liquids. 40% are for gas. At the best price.

A wide variety of Float Flow Meter options are available to you, such as free samples, paid samples.

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

The top supplying country is China (Mainland), which supply 100% of the Float Flow Meter respectively.

Sino-Inst sells through a mature distribution network that reaches all 50 states and 30 countries worldwide. Float Flow Meter 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.

Metal Tube Rotameter

The Metal Tube Rotameter uses the variable area measurement principle. The intelligent metal tube float flowmeter has a local display type and an intelligent remote transmission type, with the transmitter. Metal Tube Rotameter can be used to measure the flow of liquid, gas, and steam. It is especially suitable for medium flow measurement with a low flow rate and small flow.

Metal tube rotameter with transmitter

Metal tube rotameter with the transmitter is also called digital rotameter. All-metal structure, there are indicator type, electric remote transmission type, corrosion-resistant type, high voltage type, jacket type, explosion-proof type.

Electric remote transmission, explosion-proof design. Explosion-proof mark Exd Ⅱ CT6. Optional HART protocol function. DC24V power supply, the on-site pointer indicates instantaneous flow. Digital display instantaneous and cumulative flow. Two-wire system 4~20mA output. There are 4 buttons on the panel to view and modify internal parameters.

Metal tube rotameter Features

  • Suitable for flow measurement of small-diameter and low-velocity media;
  • Reliable work. Low maintenance and long life;
  • The requirements for straight pipe sections are not high;
  • Wider flow ratio 10:1;
  • Two-line large LCD display. Optional on-site instantaneous/cumulative flow display. Single-axis sensitive indication with backlight;
  • Non-contact magnetic coupling transmission.
  • All metal structure, metal tube rotor flowmeter is suitable for high temperature, high pressure and strong corrosive media;
  • It can be used in flammable and explosive hazardous situations;
  • Optional two-wire system, battery, AC power supply mode;
  • Multi-parameter calibration function. With data recovery, data backup and power failure protection functions.

Extended Reading: What is difference between rotameter and flow meter

Metal tube rotameter Specifications

PerformanceTechnical parameter
Measurement rangeWater (2.5~150000) L/h; air (0.07~2000) m3/h (at 0.101325 Mpa, 20℃).
level of accuracy1.5 and 2.5 grades (PTFE).
Turndown ratio10:1 or special 5:1
Nominal pressureDN15~50≤4.0MPa; DN65~150 ≤1.6MPa.
Medium temperature-80℃~200℃ (with F46 flowmeter lining 0℃~80℃)
Liquid medium viscosityDN15<5mPa•s; DN25~150≤250mPa•s
Output4-20mA two-wire system
Pure resistive load<680Ω
Linearity<0.5%
Temperature effect<5MA/K
Ambient temperature-25℃~55℃
total heightDN15~DN150 (generally 250mm)

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

The metal tube float flowmeter is mainly composed of two parts: the measuring tube and the indicator. The measuring tube includes a conical tube or orifice, guide, stopper, float, and other components. The indicator includes a magnetic follower system, pointer, dial, circuit, and other components.

The measured medium flows through the measuring tube from bottom to top. The upper and lower ends of the float generate differential pressure to form a rising force. When the rising force of the float is greater than the weight of the float immersed in the flowing fluid, the float rises, and the annular gap area increases. Annular gap When the fluid velocity drops rapidly, the differential pressure at the upper and lower ends of the float decreases. The ascending force acting on the float decreases. Until the ascending force balances with the weight of the float immersed in the fluid, the float stabilizes at a certain position. The height of the float is that Corresponds to the size of the measured medium flow.

The float has built-in magnetic steel. When the float moves up and down with the medium, the magnetic field changes with the movement of the float.

a. For the in-situ type, the follow-up magnet in the in-situ indicator is coupled with the magnet in the float. It rotates and drives the pointer at the same time, and the current flow rate is indicated by the dial.

b. For the smart type, the follower magnetic steel in the smart indicator is coupled with the magnetic steel in the float. It rotates and drives the sensing magnetic steel and pointer at the same time. The magnetic field change is converted into an electrical signal through a magnetic sensor. A/D conversion, digital filtering, temperature compensation. Microprocessor processing, D/A output. LCD liquid crystal displays the instantaneous flow and cumulative flow.

Extended reading: Beginner’s Guide: Variable area flow meter

Rotameter is a common type of flowmeter. The flowmeter is an industrial instrument for measuring the flow of liquids, gases, and other media. There are many types of flow meters. Such as electromagnetic flowmeter, turbine flowmeter, vortex flowmeter, and so on. Different flow meters have different measurement principles. For example, the electromagnetic flowmeter is based on the principle of electromagnetic induction. The rotameter is a device that estimates the flow rate by measuring the (position) of the rotating parts installed in the DC pipeline.

Extended reading: How does a rotameter work

The flow detection element of the float flowmeter is composed of a vertical tapered tube that expands from bottom to top and a float group that moves up and down along the axis of the tapered tube. Below, I will give you a specific introduction to the classification of rotameters.

Glass rotameter:

Glass rotor flowmeters are mainly used in various departments such as the chemical industry, petroleum, light industry, medicine, fertilizer, chemical fiber, food, dyes, environmental protection, and scientific research. Used to measure the flow of single-phase non-pulsating (liquid or gas) fluids. The anti-corrosion glass rotor flowmeter is mainly used for the detection of corrosive liquid and gas medium flow. Such as strong acid, strong acid, oxidant, strong oxidizing acid, organic solvent, and other corrosive gas or liquid medium flow detection.

Extended reading: Gas Rotameter Tips

Plastic tube rotameter:

The main parts such as the liquid plastic tube rotameter cone tube are made of AS, ABS plastic. Has relatively good corrosion resistance. The product also has the characteristics of reasonable structure, small size, lightweight, and the tapered tube is not easily broken. The plastic tube rotor flowmeter can be widely used in chemical, environmental protection, food, and other industrial sectors.

Plexiglass rotameter:

Plexiglass rotameter is divided into panel type plexiglass rotameter and pipeline type plexiglass rotameter.

Plexiglass rotameter also has the characteristics of high transparency, intuitive reading, not easy to break, lightweight, long life, and convenient installation and connection. However, the tapered glass tube of plexiglass cannot be used for organic solvents (such as trichloroethylene, dichloroethane).

Metal tube rotameter:

Metal tube rotameter is divided into on-site pointer indication type and remote transmission type.

Metal float flowmeter is a kind of flow measuring instrument commonly used in industrial automation process control. It has the characteristics of small pressure loss, large detection range (range ratio 10:1), and convenient use. It can be used to measure the flow of liquid, gas, and steam. It is especially suitable for medium flow measurement with low flow velocity and small flow.

Extended reading: Vortex Steam Flow Meter

The metal float flowmeter has a local display type and an intelligent remote transmission type. With pointer display. Instantaneous flow, cumulative flow, liquid crystal display. Upper and lower limit alarm output. Cumulative pulse output, standard two-wire 4-20mA current output, and other forms. Provide users with a very wide choice of space. In addition, the instrument uses a high-quality MCU micro-processing system. Ensure the excellent performance of the flowmeter in various applications.

Extended reading: Beginner’s Guide: Variable area flow meter

Digital Rotameter

Digital rotameters are easier to read than analog rotameters as well as pointer-displayed rotameters.

Digital rotameters is a smart transmitter added to the original rotameters.

The metal shell has a built-in intelligent circuit board. Intrinsically safe explosion-proof structure design, explosion-proof mark iallCT5.

The indicator has both a separate mechanical pointer for instantaneous flow. There are also five liquid crystal digital display instantaneous flow and eight digital display cumulative flow. And equipped with button operation, human-computer interaction interface. It can also output 4-20MA current signal, upper and lower limit alarm and other signals.

Digital rotameters also have a variety of parameter calibration, setting functions, data backup, data recovery and power failure protection. In addition, when it is not a two-wire power supply mode, the LCD backlight display function is also selected.

Related Products:

More Flow Measurement Solutions

Extended reading: Radar level sensor for solids – Dust solid level measurement

Metal Tube Rotameter price

Sino-Inst offers over 30 Metal Tube Rotameter products. About 50% of these are for liquids. 40% are for gas. At best price.

You can refer to the product price of the following Rotameter flow meter price:

MMetal Tube Rotameter
Pipe size 1/2 inch
Medium: oxygen
FOB Price: USD 281.50/pc

Check more Choosing The Right 1 Inch Flow Meter.

A wide variety of Metal Tube Rotameter options are available to you, such as free samples, paid samples.

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

The top supplying country is China (Mainland), which supply 100% of the Rotameter flow meter respectively.

Sino-Inst sells through a mature distribution network that reaches all 50 states and 30 countries worldwide. Metal Tube Rotameter 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.

Ultrasonic level transmitter VS Radar level transmitter

Radar level transmitter and Ultrasonic level transmitter are both liquid level measuring instruments. The most obvious difference is that one uses electromagnetic waves and the other uses ultrasonic waves. So, besides that, what is the difference between a Radar level transmitter and an Ultrasonic level transmitter?

List of Differences: Radar vs Ultrasonic Level Measurement

Here, we first list the main differences between radar level gauges and ultrasonic level gauges. You can get answers directly and clearly.

  • The radar level gauge uses the microwave generated by the radar to complete the measurement work. Ultrasound is realized in the form of sound waves. This is also the essential difference between the two.
  • The temperature of the measuring medium is different. The temperature of the medium measured by the ultrasonic level gauge does not exceed 80°C. The radar level gauge is different, the medium temperature can be as high as 1200 ℃.
  • The operating conditions and environments are different. There are many styles of radar level gauges, such as: horn type, drop type, rod type, etc., so it can be applied to different working conditions. Ultrasonic liquid level gauges cannot be used in working conditions such as vacuum and corrosion-resistant liquids.
  • Accuracy and range are different. The accuracy of radar level gauge is much higher than that of ultrasonic level gauge. The range of the radar level gauge can reach 0-100M, and the range of the ultrasonic level gauge is only 0-30M.
  • This is about the price. Relatively speaking, the radar level gauge has a wide range of applications and a high temperature measurement medium. The price is also understandable. If the ultrasonic level gauge can meet the demand, it can also be selected.

The above 5 points have briefly summarized the differences between radar liquid level measurement and ultrasonic liquid level measurement.

Therefore, when we purchase, which instrument to choose as our measuring instrument should be combined with the conditions of our measured medium before making a choice. Don’t choose blindly.

If you want to continue to understand the details of Radar vs Ultrasonic Level Measurement, then please read on.

Ultrasonic technology is not only used to measure level, but also can be used to measure depth. Get more.

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

Ultrasonic VS Radar level transmitter – working principle

  1. Radar level transmitter

Radar level transmitter adopts the circuit design of a high-frequency microstrip line structure, and the internal circuit generates a 25GHz microwave pulse signal. Based on the design principle of the high-frequency waveguide, the microwave pulse is emitted from the end of the antenna through the PTFE emitter. When the transmitted pulse hits the surface of the measured medium, part of the energy is reflected back and received by the same antenna. Through the principle of time extension technology, the time interval between the transmitted pulse and the received pulse can be calculated. Then calculate the distance from the antenna to the surface of the measured medium.

Extended Reading: bin level measuring system

  1. Ultrasonic level transmitter

An ultrasonic level transmitter is a digital level meter controlled by a microprocessor. In the measurement, pulsed ultrasonic waves are emitted by the sensor (transducer). The sound waves are received by the same sensor after being reflected by the surface of the object and converted into electrical signals. The distance between the sensor and the object to be measured is calculated from the time between the emission and reception of the sound wave. Due to the non-contact measurement, the measured medium is almost unlimited. It can be widely used to measure the height of various liquid and solid materials.

From the above two principles, we can see the following two differences:

  1. Radar level transmitter emits electromagnetic waves. The wave speed has nothing to do with ambient temperature, smoke, pressure, etc. It’s the same even in a vacuum. The propagation speed is always the speed of light.
  2. Ultrasonic level transmitter emits ultrasonic waves, which are mechanical waves. Like sound waves, its propagation speed is closely related to the state of the propagation medium. Ultrasonic level gauges are used to measure the liquid level of atmospheric vessels. The probe contains a temperature measuring element that can compensate the temperature of the wave velocity. Because of the material. The temperature range used is relatively not very wide.

Extended reading: The Secret of Ultrasonic Level Measurement

Extended Reading: What is level transmitter working principle?

Read more about: Common River Water Level Measurement Methods

Ultrasonic VS Radar level transmitter – transmission method components are different

For example, ultrasonic waves are emitted by the vibration of piezoelectric materials. So Ultrasonic level transmitter cannot be used in high pressure or negative pressure occasions. Generally only used in atmospheric pressure vessels. The Radar level transmitter can be used in high-pressure process tanks.

The launch angle of radar is larger than that of ultrasonic. Non-contact radar is not recommended for small containers or elongated containers. Guided wave radar is generally recommended. Finally, there is the question of accuracy. Of course, the accuracy of radar is definitely higher than that of ultrasound. The high-precision radar must be used on the storage tank instead of ultrasonic. In terms of price, compared with an Ultrasonic level transmitter, the price of a Radar level transmitter is relatively high. Of course, the price of some large-scale ultrasounds is not low. Such as the range of 6 to 70 meters. The Radar level transmitter can’t reach a very large range. Only an Ultrasonic level transmitter can be selected.

Extended reading: Drop Antenna Radar Tank Level Sensor

Extended reading: Dam water level measurement

Ultrasonic VS Radar level transmitter-different applications

The different working principles result in a big difference between the applications of Radar level transmitters and Ultrasonic level transmitters. It is specifically manifested in the following aspects:

  1. Because the Radar level transmitter uses electromagnetic waves. It is greatly affected by the dielectric constant of the measured substance. The ultrasonic wave used in the Ultrasonic level transmitter is a mechanical wave. Mainly affected by the density of the measured medium. Therefore, when the dielectric constant of the measured substance is very low, Ultrasonic level transmitter should be used for measurement instead of Radar level transmitter.
  2. The measurement range of Ultrasonic level transmitter is not as large as Radar level transmitter. Radar emits electromagnetic waves, which can be measured without the aid of a propagation medium. Ultrasonic waves are sound waves and mechanical waves, which need to be propagated by means of a propagation medium. Therefore, the ultrasonic level gauge has many limitations in the application process:

(1) Ultrasonic level transmitter cannot be used in working conditions such as vacuum, high steam content or foam on the liquid surface.

(2) Ultrasonic level transmitter has temperature and pressure limitations. The temperature at the probe of the Ultrasonic level transmitter generally cannot exceed 80 degrees, and the speed of the sound wave is greatly affected by temperature. Ultrasonic level transmitter is greatly affected by pressure, generally within 0.3MPa. Because sound waves are generated by vibration, the sound-producing parts will be affected when the pressure is too high. Extended Reading: GWR Level Sensor for High Temperature & High Pressure

(3) Ultrasonic level transmitters cannot measure well when there is a lot of fog or dust in the measurement environment. More about Top 5 Ultrasonic Level Sensor Applications.

In contrast, because the radar is an electromagnetic wave, it is not affected by vacuum. The applicable range of medium-temperature and pressure is also very wide. With the advent of high-frequency radar. Its application range is even wider. Under the same conditions, the Ultrasonic level transmitter is more limited.

  1. The pressure occasions of the two applications are different. Because of the different transmission methods of radar and ultrasonic components. For example, ultrasonic waves are emitted by the vibration of piezoelectric materials. So Ultrasonic level transmitter cannot be used in high pressure or negative pressure occasions. Generally only used in atmospheric pressure vessels. The Radar level transmitter can be used in high-pressure process tanks.
  2. Radar level transmitter has horn type, pole type, cable type, etc. to choose from. Can be applied to different measurement occasions. Compared with ultrasonic level gauges, Radar level transmitters can be used in more complex working conditions.
  3. The launch angle of radar is larger than that of ultrasonic. Non-contact radar is not recommended for small containers or elongated containers. Guided wave radar is generally recommended. Finally, there is the issue of accuracy. Of course, the accuracy of radar is higher than that of ultrasound. The high-precision radar must be used on the storage tank instead of ultrasonic.
  4. In terms of price, Radar level transmitter is more expensive than Ultrasonic level transmitter. Of course, some large-range Ultrasonic level transmitters are expensive. The Radar level transmitter can’t reach the very large range, so you can only choose the ltrasonic level transmitter.

Extended reading: FMCW Radar Level Transmitter 120GHz

Extended Reading: Dielectric constant for radar level transmitter

However, whether it is a Radar level transmitter or an ultrasonic level transmitter, you must pay attention to the installation location and blind spots during the installation process. For example, when installing on the tank, do not install it near the feed inlet and the human ladder. At the same time, keep a distance of 300 to 500mm from the tank wall to prevent echo interference. When there is agitation and the liquid level fluctuates greatly, a suitable installation method should also be selected.

Extended reading: guided wave radar level sensor advantages and disadvantages

More Level Measurement Solutions

Our conclusions:

We cannot say that the radar level meter must be better than the ultrasonic level meter.

Both radar level meter and ultrasonic level meter can be better used for liquid level measurement.

But which level meter should be used in practical application? It should be determined according to the process conditions, medium characteristics, combined with installation conditions, use environment and other factors. Read more about: Ultrasonic Level Sensors for Liquids Applications

Sino-Inst has been committed to providing customers with liquid level and material level measurement solutions for many years. Experience. We supply ultrasonic level meter, explosion-proof ultrasonic level meter, radar level meter, hydrostatic pressure level meter, etc.

If you need to choose between the two. Then we must sort out the measurement conditions first, and then choose the appropriate level meter. You can also consult our sales engineers.

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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 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

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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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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.

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

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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.

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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