Monthly Archives: June 2021

Water depth sensor- Water level sensor Solutions

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How do you measure the depth of water?

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.

RFQ More level sensors
Water depth sensor- Water level sensor Solutions

At present, the common measurement principle of liquid level meter in the industry involves mechanics, thermal, electrical, optical, and other aspects. The product models even reach hundreds of kinds. Of course, different types of level meters mean that they are produced, used, and calibrated in different ways. It is not possible to fit all measurement environments.

Water Depth/Level Sensors Types

The following will be from the perspective of the measurement method, for the current market more than ten kinds of liquid level meter classification. To help users in the selection of products to make the appropriate choice.

Water Depth Sensors measured by buoyancy

The buoyancy type level meter has a float (float ball or float). The float is in equilibrium on the static liquid level. When the liquid level changes, the float is displaced with the liquid level. The electronic component acquires the float displacement in a certain way. And then converted to the liquid level change.

Due to the different ways of receiving float displacement by electronic components, the buoyancy method liquid level meter is divided into magnetic flap level meter, float level meter, magnetostrictive level meter, etc.

Magnetic level meter consists of magnetic float, cylindrical container, scale and transmitter.

The float moves with the liquid level in the container, and the magnetic field of the float acts on the sensor. The sensor is a strip of rubber-sealed in a stainless steel tube of equal length to the measured liquid level. There are numerous reed switches welded to it at intervals of 1cm or less.

When the reed switch is at the same level as the float, it closes. Otherwise, the transmitter receives the current signal generated by the amount of resistance connected to the reed switch, which is converted to the liquid level.

Float movement is shown on the scale as a red and white bead flip, indicating the liquid level.

Extended reading: Water Tank Level Controller

Float level meter has a float, spring, magnetic steel chamber and indicator, designed according to Archimedes’ law and magnetic coupling principle.

The displacement of the float causes the magnetic field of the magnet chamber to change. The magnetic sensor inside the indicator precisely measures the change of the surrounding magnetic field.

Float Level Sensors – Single and Multipoint

The magnetostrictive level meter is mainly composed of float, waveguide, and transmitter.

The electronic component of the transmitter generates a low-voltage current pulse, which starts timing and generates a magnetic field that propagates down the magnetostrictive line.

The float moves along the measuring rod as the level changes, and the magnet inside the float also generates a magnetic field. When the two magnetic fields meet, the magnetostrictive lines are twisted to form a torsional stress wave pulse. The velocity of the pulse is known, and the pulse propagation time is calculated to correspond to the exact change in the liquid level.

Magnetostrictive Level Transmitters

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

Liquid level meter measured by pressure

The level meter of pressure method is the level meter that reflects the liquid level by measuring the liquid pressure through its pressure measuring element. It is generally composed of transmitter, sensor and pressure probe. The sensor is a special metal rod or cable with a built-in capillary hose, and the probe is constructed as a stainless steel cylinder core with a diaphragm at the bottom.

The probe intrudes into the liquid and tests the difference between the static pressure of the liquid and the actual atmospheric pressure, which varies with the liquid level. The electronic components receive the differential pressure signal to reflect the change in liquid level. According to the different materials of sensors are divided into two types of rod and cable type.

Rod type pressure level meter sensor is a metal rod. Its general technical parameters are, the measurement range is generally 0 ~ 5m, output signal: (4 ~ 20) mA, measurement accuracy is generally ± 0.5%.

SMT3151TR Submersible Level Transmitter
Hydrostatic level transmitter is also called hydrostatic level gauge. The rod-type Hydrostatic level transmitter 4-20mADC standard signal output. Flange or threaded installation. Can withstand high temperatures up to 450 ℃.

Because the sensor is a cable, can be bent, convenient handling and loading, so the range of the cable type pressure level meter can be very large, there are 100m, or even 300m, its measurement accuracy is generally ± 1.0%.

SI-151 Hydrostatic Level Sensor
Hydrostatic Level Sensor (Best Price), also called Hydrostatic level transmitter. Continuous level measurement in liquid applications with pressure sensors.

Differential pressure level meter is also through the detection of pressure differences to measure the liquid level.

The level meter has two pressure-taking ports in the gas phase and liquid phase.

The pressure at the gas phase pressure point is the pressure of the gas phase in the equipment. The pressure at the liquid phase pressure point is not only affected by the gas phase pressure, but also by the static pressure of the liquid column.

The difference between the liquid phase and gas phase pressure is the static pressure generated by the liquid column, which is converted into the liquid surface height.

Flange Mounted Differential Pressure Transmitter
Extended Diaphragm Seal DP Level Transmitter
Remote Seal Differential Pressure Transmitter
Differential pressure(DP) level transmitter

Liquid level meter measured by reflection

At present, there are two main types of reflective level meters: radar level meter and ultrasonic level meter. Their principles are basically the same, they are through the emission – reflection – reception of ultrasonic or electromagnetic wave (radar wave) way to measure the liquid level height.

Radar level measurement uses Non-contacting radar technology for Continuous level measurement. Liquids and solids are commonly measured with this measuring technique.

Radar level transmitters use radar technology to perform non-contact continuous level measurement. The radar level indicator converts the level into an electrical signal. The level signal output can then be utilised by other instrumentation to monitor or control. Liquids and solids are commonly measured with this measuring technique. Like: Fly ash silo. Radar level sensors are divided into: Pulsed radar technology and frequency modulated continuous wave (FMCW) radar level sensors.

Sino-Inst produces a 120GHz FMCW radar level sensor, 26GHz radar level meter, 6GHz level meter.

Extended reading: Radar Level Meter for Corrosive Liquids

Extended reading: Radar Water Level Sensor Applications

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

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

Extended Reading: Wireless Water Meter

Liquid level meter through the conductive method of measurement

Level meters in the conductive mode are based on the electrical principle. The level is measured by means of measuring capacitance or resistance. This type of level meter mainly includes capacitance level meter, radio frequency conductivity level meter, resistance level meter.

The Capacitance level meter uses the change of measuring capacitance to measure the level of the liquid.

By a metal rod inserted into the liquid container, the metal rod is a pole of capacitance, the container wall is the other pole of capacitance. The medium between the two electrodes is the liquid and the gas above it.

As the dielectric constant of the liquid and the dielectric constant of the gas on the liquid surface is different, the level of the liquid is measured by the change of the capacitance between the two electrodes.

Extended reading: Capacitive water level sensor

RF conductivity level meter is an upgraded version of capacitance level meter, which can be understood as measuring conductivity with high frequency radio waves.

When the instrument works, the sensor of the instrument and the filling wall, and the measured medium form the conductivity value. When the level changes, the conductance value changes accordingly. The circuit unit converts the measured conductance value into a level signal output. To achieve the level measurement.

Extended reading: Radar Non Contact Water Level Sensor

Deep Well Water Level Sensor

Deep Well water level sensor is to apply Hydrostatic Level Sensor to deep well. The Well water level sensor submerged in deep well works together with a submersible water pump. The range within 300m ～ 1000m.

Deep Wells Water level sensor is based on the principle that the measured liquid pressure is proportional to the height of the liquid. The piezoresistive effect of the advanced foreign isolated silicon diffused sensor is used. Change to electrical signal. After temperature compensation and linear correction, convert to 4-20mA standard electrical signal. Well water level sensor submerged in deep well work together with water pump. It is extremely difficult to replace and submit an inspection. Therefore, it adopts stainless steel cable, waterproof, sealing ring, and other four-level seals. Special cables and special water sealing technology make the transmitter highly reliable and stable.

Extended Reading: 3 inch (3″) Water Flow Meter

Portable Ultrasonic Water Depth Gauge

Water Depth Gauge is a portable water depth detector based on the principle of ultrasound. Ideal water depth measuring instrument for ships, oceans, reservoirs, lakes, rivers, and shallow water level monitoring.

Water Depth Gauge is a necessary instrument to measure water depth in reservoir, lake, river, shallow sear. Place ultrasonic transducer on water surface or into a certain position into water. The device can caculate current water depth. HS-SFCC Portable Ultrasonic Water Depth Gauge It has perfect water depth measurement function. Control function, data transmission function and man-machine communication function. This machine integrates ultrasonic transceiver sensor, servo circuit, temperature compensation sensor and compensation circuit unit, display, control signal output and serial data or analog output unit (optional) as a water depth measuring instrument. It has the characteristics of low maintenance, high reliability, long life, convenient use, simple operation and accurate measurement. Therefore, it is widely used in water area monitoring.

Read more about: Common River Water Level Measurement Methods

How do you measure water level in tank with sensor?

The Water Tank Level Sensor is an important part of the water tank level control system. Using a level sensor for the water tank, solenoid valve, control box, liquid level switch and other accessories can effectively form a Water Tank Level control system. Monitor the materials stored in the water tank. Master important data such as its liquid level, reserves, and quality. A reasonable liquid level can ensure the safe, reliable, and efficient operation of the storage tank.

Read more about: Water Tank Level Sensors for Level Control

More Level Measurement Solutions

Sino-Inst offers over 20 Water depth sensors for level measurement.

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

A wide variety of Water depth sensors 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.

How to Select Ultrasonic flow detectors?

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What is an ultrasonic flow detector?

An ultrasonic flow detector is often understood as an ultrasonic flow meter or ultrasonic transducer. In fact, an Ultrasonic flow detector refers to the probe part of the ultrasonic flow meter or sensor part. Ultrasonic flow detectors can be equipped with different ultrasonic flow detectors to meet different measurement needs. For example, a portable ultrasonic flowmeter can be equipped with a clamp Ultrasonic flow detector. commonly used in water, oil, and other single liquid flow rate detection.

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Ultrasonic flow detectors types

Ultrasonic flow detectors can be divided into external paste type, insertion type, and pipe section type according to the installation method.

A) Clamp-on type

External paste type ultrasonic flowmeter is produced earlier, the user is more familiar with and more widely used ultrasonic flowmeter. Installation of the transducer without pipeline disconnection. That is posted that use, it fully embodies the ultrasonic flowmeter installation is simple, easy to use characteristics.

Extended reading: Portable ultrasonic flow meter for water

B）Pipe section type

Certain pipelines due to material sparse, poor sound conduction, rust and corrosion is serious. Lining and pipeline space with gaps and other reasons. Resulting in serious ultrasonic signal attenuation. Ultrasonic flowmeter with external paste type can not be measured normally. Generated the pipe segment ultrasonic flowmeter.

Pipe segment ultrasonic flowmeter to the converter and measuring tube composition as a whole, to solve the external paste flowmeter measurement in a problem. Measurement accuracy is also higher than other ultrasonic flowmeter. But at the same time also sacrificed the advantages of the external paste type ultrasonic flowmeter non-flow installation. Requires the installation of the transducer to cut the pipe.

Extended Reading: Inline Ultrasonic Flow Meter

C) Insertion type

Insertion type ultrasonic flowmeter in between the above two. Installation can be non-stop flow, the use of special tools have water pipes on the hole, the transducer into the pipe, complete the installation. Transducer pipeline, its signal emission, receiving only the measured medium. Its measurement is not limited by the pipe quality and pipe lining materials.

TM series standard clamp-on Ultrasonic flow detectors

  • With a strong magnet, when measuring steel and cast iron pipes, the sensor only needs to be adsorbed on the outer wall of the pipe.
  • Equipped with a ground terminal, can be used in the occasion of strong electromagnetic interference.
  • Can be fixed by a steel belt, steel wire rope, tensioning belt, special clamps.
  • The upper cover of the sensor is marked with the direction of ultrasonic signal emission.
  • The protection level can reach IP68 after the junction box is filled with glue.
  • Complete specifications, divided into large, medium, and small models, measuring pipe diameter range: DN15~DN6000mm.
  • Temperature range: -40~90℃.
  • According to the different uses, the standard clamp-on sensors are divided into two categories: portable and stationary.

1 Tensioning belt fastening groove
2 Wire rope fastening groove
3 Steel belt fastening slot
4 Top cover fastening screw
5 Signal emission direction indication arrow
6 Sound wedge
7 Powerful magnets
8 Anti-slip groove

9 Upstream and downstream sign sticker
10 Cable interface
11 Installation distance measurement starting and ending points
12 Product information label
13 Positive terminal block
14 Negative terminal block
15 Ground terminal block
16 Junction box

Clamp-on Ultrasonic Flow Meter Working Principle

Clamp on Ultrasonic Flow Meter adopts the measurement principle of time difference method. It uses the ultrasonic wave emitted by the sensor to propagate in the flowing fluid. The sound wave propagation speed in the downstream direction will increase, and the backward direction will decrease. In the same propagation distance, there will be different transmission times. According to the difference between the transmission time and the measured The relationship between fluid velocity measures the fluid velocity.

The flow rate of the fluid is different in different positions in the tube. The flow rate in the center of the tube is faster than the flow rate near the wall of the tube. The flow velocity distribution of the fluid in the pipeline can be represented by the flow velocity cross-sectional distribution diagram.

By setting the flowmeter and considering the cross-sectional distribution of the flow velocity, the average flow velocity can be calculated. Then the volume flow of the fluid can be obtained according to the cross-sectional area of the pipe.

Notes:
V measure fluid velocity
M ultrasonic reflection times
D pipe diameter
θ The angle between the ultrasonic signal and the fluid
T up The time when the downstream sensor transmits the signal to the upstream
T down Time from upstream sensor to downstream
ΔT = T up – T down

Guess You’ll Like: Ultrasonic flow meters types & technical guide

HT series high temperature clamp-on ultrasonic flowmeter sensor

  • With high temperature resistant powerful magnet, when measuring steel and cast iron pipes, the sensor only needs to be adsorbed on the outer wall of the pipe.
  • Equipped with ground terminal, can be used in the occasion of strong electromagnetic interference.
  • Can be fixed by steel belt, steel wire rope, tensioning belt, special clamps.
  • The upper cover of the sensor is marked with the direction of ultrasonic signal emission.
  • The protection level can reach IP68 after the junction box is filled with glue.
  • Complete specifications, divided into large, medium and small specifications, measuring pipe diameter range: DN15~DN6000mm,
  • Temperature range: -40~160℃.
  • According to the different uses, high temperature clamp-on sensors are divided into two categories: portable and fixed.

1 Tensioning belt fastening groove
2 Wire rope fastening groove
3 Steel belt fastening slot
4 Top cover fastening screw
5 Signal emission direction indication arrow
6 Sound wedge
7 Powerful magnets
8 Anti-slip groove

9 Upstream and downstream sign sticker
10 Cable interface
11 Installation distance measurement starting and ending points
12 Product information label
13 Positive terminal block
14 Negative terminal block
15 Ground terminal block
16 Junction box

Extended reading: Flow Totalizer F3000X for Data collection and calculation

Other commonly used ultrasonic flow detectors:

What Does an Ultrasonic Doppler Flow Detector Measure?

From the ultrasonic measurement principle, the time difference method is suitable for measuring pure and less impurity liquids. Such as tap water, river seawater, sewage treatment plant effluent, etc. The Doppler method is suitable for measuring liquids and slurries with a high impurity content. Such as urban drainage, mud, pulp and so on.

Judging from the company’s years of practical experience, the two measurement methods are relatively vague for the quantitative indicators of the impurity content of the measured medium. The main reason is that there is currently no effective instrumentation for measuring the impurity content of liquids.

Doppler ultrasonic flowmeter flow rate measurement is based on the Doppler effect. The probe emits a beam of ultrasonic waves obliquely upward. Ultrasound propagates in fluids. The fluid will contain impurities such as bubbles or particles (it can be considered that the impurities in the fluid are at the same speed as the water flow).

When the ultrasonic wave contacts the impurities in the fluid, the reflected ultrasonic wave will produce a Doppler frequency shift Δf. The Doppler shift Δf is proportional to the flow velocity. The flow velocity of the fluid can be measured by measuring the Doppler frequency shift Δf.

The Dopp ultrasonic flowmeter uses the velocity area method to measure the flow. The flow velocity V is measured using an ultrasonic flow velocity sensor. Use a pressure water level gauge to measure the water level H. The channel parameters set in the controller in advance. The controller can use the water level to automatically convert the flow area S. The formula for the flow rate of the fluid is:

Q= V×S

Wherein V- – – -flow velocity S- – – -flow area Q- – -instantaneous flow

Since the velocity area method is used to measure the flow, it can be applied to any shape of the section.

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FAQ

Ultrasonic flowmeter refers to a flowmeter developed based on the principle that the propagation velocity of ultrasonic waves in the flow medium is equal to the average flow velocity of the measured medium and the vector sum of the velocity of the sound waves in the stationary medium.

According to the principle of signal detection, ultrasonic flowmeter can be divided into propagation speed difference method (direct time difference method, time difference method, phase difference method and frequency difference method), beam shift method, Doppler method, mutual correlation method, spatial filtering method and noise method, etc.

Our time difference ultrasonic flowmeter: measuring the time difference caused by the difference in propagation velocity when propagating downstream and upstream to calculate the measured fluid velocity.

The measurement accuracy of the ultrasonic flowmeter is very high. Almost no interference from various parameters of the measured medium.

Sino-Inst manufactures and supplies ultrasonic flow meters with an accuracy of 1%. This accuracy can meet the measurement needs of most customers.

In particular, it can solve the flow measurement problems of strong corrosive, non-conductive, radioactive and flammable and explosive media that other instruments cannot.

So what causes the inaccurate measurement of the ultrasonic flowmeter?

The following are the reasons for the inaccurate measurement:
The influence of pipeline parameter equipment on the accuracy of ultrasonic flowmeter measurement.
The influence of upstream and downstream straight pipes on the accuracy of ultrasonic flowmeter measurement.
The influence of couplant on measurement accuracy.
The influence of the installation position of the ultrasonic flowmeter transducer on the measurement accuracy.

Sino-Inst produces and supplies ultrasonic flow meters mainly for measuring water, seawater, industrial sewage, acid and alkaline liquids, alcohol, beer, various oils, and other single homogeneous liquids that can conduct ultrasonic waves. Of course, there are also ultrasonic flowmeters that can measure gas.

According to the measurement method can be divided into Doppler ultrasonic flowmeter, time difference ultrasonic flowmeter, hybrid ultrasonic flowmeter.

A）Doppler type ultrasonic flowmeter

B) time difference ultrasonic flowmeter

C）Mixed ultrasonic flowmeter

Related products:

Find more Ultrasonic Flow Meters for Liquids|Clamp-on|Insertion|inline

Sino-Inst, Manufacturer for Ultrasonic flow detectors. It can measure a single sound-conducting liquid medium of DN 15—150mm. It can measure even liquids such as water, seawater, oil, and slurry.

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

Irrigation Flow Meters for Agriculture Water System

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What is an irrigation flow meter?

The irrigation flow meter is a flow meter designed for agricultural irrigation water counting. Agriculture, horticulture, etc. require water for irrigation. And water is becoming more and more expensive. The installation of flow measurement devices allows for effective monitoring and management of agriculture water systems.
The old mechanical water meters and today’s ultrasonic flow meters and electromagnetic flowmeters are widely used.

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Agricultural irrigation water system

It consists of irrigation canal head project, water transmission and distribution project and field irrigation project.

①Irrigation canal head project has reservoirs, pumping stations, dammed diversion projects, damless diversion projects, wells and other forms. Used to draw irrigation water at the right time and in the right amount.

② water transmission, water distribution projects include channels and canal buildings. Its task is to safely transport and reasonably distribute the water introduced at the head of the canal to all parts of the irrigation area. According to its function and scale, the general fixed channel is divided into dry, branch, bucket, agricultural four levels. Depending on the size of the irrigation area and the terrain, the number of levels of channels can be increased or decreased appropriately. Drainage buildings include diversion buildings, water measuring buildings, restraint buildings, articulation buildings, cross buildings, flood drainage buildings, drainage buildings, etc.

③ Field irrigation project refers to the temporary furrows, water transmission monopoly ditches and field irrigation ditches below the agricultural canals, border fields, and temporary water distribution and water measurement buildings. Used to irrigate the farmland. To meet the needs of normal crop growth or soil improvement.

Extended reading: Industrial VS Residential inline water flow meters

Irrigation flow meters for sale

Magnetic Water Flow Meter
Remote Magnetic Sewage Flow Meter
Insertion Magnetic Flow Meter
Handheld Ultrasonic Flow Meter
Ultrasonic Clamp on Flow Meter
Dual Channel Ultrasonic Water Meter

A magnetic Flow Meter is a flow meter that measures the flow of conductive fluids. Abbreviated as EMF, also called Electromagnetic flowmeters. It is a kind of Volumetric flow meter. A magnetic flow meter measures the velocity of conductive liquids moving through a pipe or conduit. In the wastewater treatment industry, a Magnetic Flow Meter is the best flow meter choice.

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

The ultrasonic flow meter measures the liquid flow rate quickly and effectively. There are two types of ultrasonic flowmeter technology: Doppler frequency shift and transit time.

Transit time ultrasonic flow meter is most suitable for measuring the flow of cleaning liquid. Therefore, it is the most popular type of ultrasonic meter.

Doppler ultrasonic flow meter can measure the frequency difference of sound waves reflected from bubbles or particles in the airflow. It is suitable for aerated or dirty liquids.

Insertion Ultrasonic Water Flow Meter-Old Style
Insertion Ultrasonic Water Flow Meter-New Style

Card-type water meter with fixed control function, according to the local climate conditions, crops or green plants growth habits, program control can set up to five timed water supply time per day, in order to achieve water-saving irrigation, scientific irrigation.

The open channel flowmeter uses an ultrasonic sensor with a Parshall groove to measure open channel flow. Ultrasonic open channel flow meter is composed of 3 parts: level sensor, water measuring sink, and flow totalizer.

Ultrasonic open channel flowmeters are used to measure the flow of fluids in non-full tubular open channels and natural flowing water surfaces. It is called open channel flow detection. The measuring flume that is not full is called an open channel. The open channel flowmeter measures the water level in the measuring weir trough and then calculates the flow rate according to the water level flow relationship of the corresponding measuring weir trough.

Extended Reading: Chilled Water Flow Meter

Radar flow meter is a fully automatic flow meter based on microwave technology. It adopts advanced K-band plane radar technology. Through non-contact way to measure the flow rate and water level of the water body. According to the built-in software algorithm, it calculates and outputs the real-time section flow and accumulated flow.

The radar flow meter can be used for non-contact flow measurement in rivers, irrigation channels, underground drainage networks, flood control, and early warning. The product features low power consumption, compact size, high reliability, and easy maintenance. The measurement process is not affected by temperature, sediment, river pollutants, floating objects on the water surface, and other factors.

Extended Reading: Collection of Industrial Insertion Flowmeter Type

Extended reading: 2 inch Water Flow Meter

river flow measurement instruments

The methods of river flow measurement are as follows:

1.Flowmeter method
The flow of the river is measured directly using a flow meter.
There are many types of flowmeters, mainly including differential pressure, electromagnetic, trough and weir flowmeters.
It can be selected and used according to the flow range of the actual flow and the test accuracy requirements.

2.Volume method
Pour river water into a container of known capacity and measure the time it takes to fill the container. Repeat the measurement several times. A method of calculating the amount of water by finding its average value t(s).
The method is simple and easy to implement and has high measurement accuracy. Suitable for rivers with small river flow.
However, there should be an appropriate drop between the overflow port and the receiving water body, or an aqueduct can be used to form an error.

3.Buoy method
Select a straight river reach, and measure the cross-sectional area of ​​the water flow within a 2m interval of the river reach. Find the area of ​​its average cross-section.
Drop buoys in the upper reaches of the river and measure the time it takes for the buoys to flow through the identified reaches (L).
Repeat the measurement several times to obtain the average value (t) of the required time.
The flow rate (L/t) can be calculated.
The flow can then be calculated as follows:

Q=60V*S

where Q is the water flow, and the unit is m^3/min.
v is the average velocity of water flow, and its value is generally 0.7L/t, m/s.
S is the average cross-sectional area of ​​water flow, in m^2.

4.Flow meter method
By measuring the cross-sectional area of ​​the water flow, the river flow rate is measured with a current meter to calculate the river flow.
When measuring, the number of vertical measuring points and the number of horizontal measuring points need to be determined according to the depth and width of the channel.
This method is simple, but it is easily affected by water quality, and it is difficult to achieve continuous determination.

5.Acoustic Doppler flow velocity measurement
Acoustic Doppler flow velocity measurement is developed using the principle of acoustic Doppler. It can simultaneously measure the cross-sectional shape, water depth, flow velocity and flow rate of the river bed at one time, and is suitable for flow monitoring of large rivers.

The flowmeter’s host and transducer are housed in a waterproof container. All immersed in water when working. It is connected with a portable computer through a waterproof cable, and the operation and control of the flowmeter are carried out on the portable computer.
From the initial blind zone of more than 1m, it has been reduced to the so-called “zero blind zone”. The section unit is reduced to the current 0.05~0.25m. Make it possible to apply it on wide and shallow rivers.

Read more about: Common River Water Level Measurement Methods

Battery operated electromagnetic flow meter-GRPS-new irrigation water flow meter

GPRS wireless remote electromagnetic flowmeter inherits the advantages and functions of the original electromagnetic flowmeter and supports GPRS wireless communication.

Only a mobile phone card with GPRS wireless Internet access function is required, and you can easily log in to the Internet and establish a connection with a remote computer without connecting other module devices. Support Kingview.

The battery-powered converter comes standard with a regular lithium battery pack that lasts 3–6 years. If equipped with a high-capacity lithium battery pack, the continuous working time will be longer.

It can easily realize remote monitoring of the electromagnetic flowmeter’s instantaneous flow, instantaneous flow rate, flow percentage, fluid conductance ratio, forward cumulative value, reverse cumulative value, alarm status and other data. With disconnection automatic connection function, support dynamic IP address.

This Battery operated electromagnetic flow meter has become the choice of many users.

How to Select the Right Agriculture Flow Meter

Due to the modernization of agriculture and the realization of precision agriculture, flowmeters are bound to play an increasingly important role in farmland irrigation.
Therefore, on the basis of a comprehensive comparison of the measurement methods and characteristics of various flowmeters on the market. You should choose flow meter products that are more in line with the requirements of farmland water conservancy irrigation, safe, reliable, economical and durable.

The principle of choosing a flowmeter is to have a deep understanding of the structural principles and fluid characteristics of various flowmeters. 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 account.

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

① Performance requirements of the flowmeter;

  • Whether to measure flow (instantaneous flow) or total amount (cumulative flow);
  • Accuracy requirements;
  • Repeatability;
  • Linearity;
  • Flow range and range;
  • Pressure loss;
  • Output signal characteristics and flowmeter response time, etc.

② fluid characteristics;

  • Fluid temperature and pressure
  • fluid density
  • Viscosity
  • Chemical corrosion and scaling
  • compression factor

③ Installation requirements;

  • Field piping wiring
  • The flow direction of the fluid
  • The upstream and downstream straight pipe sections of the flowmeter
  • Pipe diameter and pipe vibration
  • The installation position of the valve
  • Protective accessories
  • Electrical connection and electromagnetic interference
  • Pulsating flow and unsteady flow

④ Environmental conditions;

  • Ambient temperature
  • Ambient humidity
  • Security
  • Electrical interference

⑤ The price of the flow meter.

  • Installation fee
  • Running cost
  • Testing fee
  • Maintenance costs and spare parts costs, etc.

Frequently
Asked
Questions

Help Center

In theory, there are many ways to measure irrigation flow.
However, from a practical application point of view I will tell you:

If it is a closed pipe, use a flowmeter. Electromagnetic flowmeters or ultrasonic flowmeters are both good choices.
If it is an open channel, then an open channel flow meter is used.

If you want to divide the flow meter into three categories. I think it can be divided into volumetric flowmeters, mass flowmeters, and velocity flowmeters.

If you choose a water meter. Then the diameter of the water meter is determined according to the rated flow of the water meter and the user’s water consumption and water use method.

If you choose a flow meter. It is necessary to combine the selection reference parameters mentioned above.

The general measurement is to use an electromagnetic flowmeter.

Magnetic flowmeters use the principle of Faraday’s Law of Electromagnetic Induction to measure the flow rate of liquid in a pipe. In the magnetic flowmeter pipe parts, a magnetic field is generated and channeled into the liquid flowing through the pipe.

As fluid flows through the magnetic field, conductive particles in the fluid create changes. This variation is used to measure and calculate the velocity of water flow through the pipe. When the fluid moves faster, more voltage is generated. The electronic transmitter processes the voltage signal to determine the liquid flow.

Read more about Digital Water Flow Meters

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Sino-Inst is Manufacturer of Irrigation Flow Meters. We supply more than 20 kinds of Irrigation Flow Meters. 60% magnetic flow meter, 20% ultrasonic flowmeters, and other types of flowmeters.

Irrigation Flow Meters are mainly used for flow measurement of Agriculture Water System.
It can measure even liquids such as water, seawater, oil, and slurry.

Irrigation Flow Meters enable stable water measurement and control. This greatly meets the measurement needs of many Farm and irrigation industry applications. Can be used from small to large tubes.

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

The entire team at Sino-Inst’s has received excellent training, so we can ensure that every client’s needs are met. For assistance with your product requirements, whether it’s a Irrigation Flow Meters, level sensor, or other device, give us a call.

Static Pressure vs Dynamic Pressure vs Total Pressure

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You may have heard of Static Pressure, Dynamic Pressure and Total Pressure. Especially in some industrial process pipe parameters. So what are Static Pressure, Dynamic Pressure and Total Pressure? What is the difference between them? How are they measured? Let’s take a look together.

RFQ Pressure Transmitters

Static pressure vs dynamic pressure vs total pressure

According to the knowledge of fluid mechanics. The vertical force acting on the unit area of the fluid is called pressure. When the air flows along the inner wall of the duct, its pressure can be divided into static pressure, dynamic pressure and full pressure. The unit is mmHg or kg/㎡ or Pa, respectively.

Static pressure (Pi).

What is static pressure?

Static pressure is the pressure generated by the air molecules hitting the duct wall due to irregular movement.
When calculating, the static pressure with absolute vacuum as the calculation zero points are called absolute static pressure.
The static pressure with atmospheric pressure as the zero point is called relative static pressure.
The static pressure of air in air conditioning refers to the relative static pressure.
The static pressure is positive when it is higher than atmospheric pressure, and negative when it is lower than atmospheric pressure.

Dynamic pressure (Pb).

What is dynamic pressure?

Dynamic pressure refers to the pressure generated by the flow of air, as long as the air flow in the duct has a certain dynamic pressure, and is positive. Dynamic pressure = 0.5 * air density * wind speed 2 .

Total pressure (Pq).

What is total pressure?

The total pressure is the algebraic sum of the static and dynamic pressures: Pq=Pi+Pb .

The total pressure represents the total energy of 1m3 of gas. If the atmospheric pressure is the starting point of the calculation, it can be positive or negative.

Extended reading: Pressure indicator transmitters

Extended reading: Pressure Sensor Applications-Featured Industry Applications

The difference between static pressure, dynamic pressure and total pressure

Different nature

  1. Total pressure: The pressure measured parallel to the wind flow, directly opposite to the direction of the wind flow.
  2. Static pressure: the pressure on the surface of an object at rest or in uniform linear motion.
  3. Dynamic pressure: When the object is moving in the fluid, the surface in the direction of the fluid movement. The fluid is completely blocked, where the fluid velocity is 0. Its kinetic energy is transformed into pressure energy, and the pressure increases.

Extended reading: wireless pressure transmitter

Features are different

1.Total pressure: air conditioning units or fresh air units are often installed at the end of the fan, the fan outlet wind speed is high, high dynamic pressure, static pressure is small. Engineering often installed at the exit of the anechoic static pressure box, reduce the dynamic pressure, increase the static pressure. At the same time, the same flow, muffling effect.

2.Static pressure: with no noise, no vibration, no impact.

3.Dynamic pressure: only the directional flow of air to show dynamic pressure. Dynamic pressure is directional, only the plane perpendicular or oblique to the direction of wind flow pressure. The plane of the vertical flow direction to bear the maximum dynamic pressure, the plane of the parallel flow direction to bear the dynamic pressure is zero. In the same flow section, because the wind speed at each point is not equal, the dynamic pressure varies. Dynamic pressure is not absolute pressure and relative pressure, always greater than zero.

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Different applications

  • Total pressure: applied to air conditioning or fan products.
  • Static pressure: applied to fluid dynamics.
  • Dynamic pressure: applied to mines, aerospace, etc.

Extended Reading: Up to 800°C High Temperature Pressure Sensor

What is an example of static and dynamic pressure?

Example of static pressure: When water is stored in a closed container, the pressure generated by the water in the container is static pressure. For example, water stored in a water tower develops pressure due to its height.

Example of dynamic pressure: When water flows in a pipe, in addition to the static pressure due to the weight of the water, there is also pressure due to the flow speed of the water. This part of the pressure is dynamic pressure. For example, the pressure created when water from a faucet hits the bottom of a wash basin.

Dynamic Pressure Calculator

Dynamic pressure is the kinetic energy of a flowing fluid – liquid or gas – per unit volume – and can be expressed as

pd = 1/2 ρ v²

Where:
pd = dynamic pressure (N/m2 (Pa), lbf/ft2 (psf))
ρ = density of fluid (kg/m3, slugs/ft3)
v = velocity (m/s, ft/s)

Online Dynamic Pressure Calculator

What is a dynamic pressure sensor?

The piezoelectric effect is the main operating principle of dynamic pressure sensors. Dynamic pressure sensors cannot be used for static measurements.

This is because the charge after an external force is only saved when the circuit has an infinite input impedance.

This is not the case in practice, so this determines that dynamic pressure sensors can only measure dynamic stresses.

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SI-338 Ceramic Pressure Sensor
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Static pressure sensor and dynamic pressure sensor difference

  1. Diaphragm pressure sensor is according to the structure of the sensor, according to the sensing principle diaphragm pressure sensor can be divided into different types such as piezoresistive, strain gauge, inductive, capacitive, piezoelectric, etc.
  2. Among the above different principles of pressure sensors, piezoelectric pressure sensors are only suitable for measuring dynamic pressure. Therefore, dynamic calibration is required; other dynamic and static pressures can be measured. The most applications belong to the quasi-static measurement of very low frequency. Therefore, static calibration is the most used form of calibration. When the measured pressure band is wide, all kinds of pressure sensors should do frequency response calibration.

Extended reading: Silicon Pressure Sensor

Applications of dynamic pressure sensors

Dynamic pressure sensors are mainly used in the measurement of acceleration, pressure and force.

Dynamic pressure sensors are also widely used in biomedical measurements. For example, ventricular catheter microphones are made of piezoelectric sensors. Because dynamic pressure measurements are so common. This is why dynamic pressure sensors are so widely used.

Dynamic pressure transducers are used in a wide range of applications, typically to measure speed, pressure, and force. Therefore, they have a very high value in some products.

Extended reading: Best Price Ceramic Pressure Sensor

Frequently
Asked
Questions

Help Center

The static pressure sensor is based on atmospheric pressure or absolute vacuum, and compares the difference between the measured pressure and atmospheric pressure or absolute vacuum.

A static pressure sensor can be thought of as a specific form of differential pressure sensor. However, due to the measurement requirements, there will be large differences in the structure of the two.

In ventilation systems, static pressure is the pressure exerted by the air inside a building relative to the outside air pressure when the exhaust fan is turned on. Measuring and maintaining proper negative pressure allows ventilation systems to mix outside and inside air more efficiently.

Extended reading: Industrial Pressure Transmitters|Buy from the manufacturer

Dynamic pressure, when an object moves in a fluid, on the surface facing the direction of fluid motion, the fluid is completely blocked. The fluid velocity here is 0. Its kinetic energy is converted into pressure energy. The pressure increases. Its pressure is called total resistance pressure . Abbreviated as total pressure or total pressure, represented by P. The difference between it and the pressure at the undisturbed place (ie static pressure, represented by P static) is called dynamic pressure (represented by P dynamic)

Extended reading: Featured Diaphragm Seal Pressure Transmitters

The duct static pressure sensor is a detection instrument that mainly detects the difference of wind pressure on both sides of the filter. Real-time data monitoring and measurement of gas positive pressure, negative pressure and differential pressure can be realized through the wind pressure sensor. Equipped with a pitot tube pressure device, it can realize the three-in-one detection of wind pressure, wind speed and air volume.

Extended reading: how to calibrate a pressure transmitter

Diaphragm pressure sensors are based on the structure of the sensor. According to the sensing principle, diaphragm pressure sensors can be divided into different types such as piezoresistive, strain gauge, inductive, capacitive, and piezoelectric.

Among the above-mentioned pressure sensors with different principles, piezoelectric pressure sensors are only suitable for measuring dynamic pressure. Therefore, dynamic calibration is required;

Other dynamic and static pressures can be measured, and the most widely used is the quasi-static measurement with a very low frequency. Therefore, static calibration is the most widely used calibration form. When the measured pressure frequency band is wide, all kinds of pressure sensors should be calibrated for frequency response.

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Sino-Inst offers over 20 Pressure Transducers.

About 50% of these are 4-20ma Low-Pressure Transducers, 40% are Differential Pressure Gauge, and 20% are Diaphragm Seal Pressure transmitters, 20% are 4-20ma differential pressure transmitters.

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

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

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

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

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

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

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The influence of Reynolds number on the accuracy of the flow meter

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What is Reynolds number?

Reynolds number is a dimensionless number that can be used to characterize the flow of a fluid. The ratio of the inertial force Fg and viscous force (internal friction) Fm during fluid flow is called Reynolds number. It is expressed by the symbol Re. Re is a factorless quantity. The Reynolds number can be used to distinguish the flow of fluid is laminar or turbulent. It can also be used to determine the resistance to the flow of an object in a fluid.

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Instrument constant of flow meters, i.e. Reynolds number

Reynolds number is an infinite parameter used as a criterion to determine the flow pattern of a fluid as it flows through a pipe. It is related to pipe diameter, flow rate, and medium viscosity.

The first used to determine the flow pattern of the fluid is turbulent flow through laminar flow. A side Re greater than 3200 or more can be judged as turbulent flow. Of course, from the laminar flow to the turbulent flow of the Reynolds number has a transition. So be specific and say that the Reynolds number must be greater than a certain value to say is to restore turbulent flow. Less than a certain value is said to be restored laminar flow.

Re = ρvd/μ, where v, ρ, μ are the fluid velocity, density and viscosity coefficient, d is a characteristic length. For example, if fluid flows through a circular pipe, d is the equivalent diameter of the pipe.

When measuring the flow rate of a fluid in a pipe, it is often necessary to understand its flow state, velocity distribution, etc. Reynolds number is to characterize the fluid flow characteristics of an important parameter.

Fluid flow inertia force Fg and viscous force (internal friction) Fm ratio called Reynolds number. Re is a factor less quantity.

The Reynolds number is small, which means that the fluid flow between the viscous force between the masses dominates, the fluid masses parallel to the inner wall of the pipe flow regularly, laminar flow state.

Reynolds number is large, which means that the inertia force dominates, the fluid is the turbulent flow state, general pipe Reynolds number Re < 2000 for laminar flow state, Re> 4000 for turbulent flow state, Re = 2000 ~ 4000 for the transition state.

In different flow states, the law of motion of the fluid. The distribution of velocity is different, so the average velocity of the fluid in the pipeline υ and the maximum velocity υmax ratio is also different. Therefore, the size of the Reynolds number determines the flow characteristics of viscous fluids.

When the external conditions are geometrically similar (geometrically similar pipes, fluid flowing through geometrically similar objects, etc.), if their Reynolds numbers are equal, the fluid flow state is also geometrically similar (hydrodynamically similar). This law of similarity is the basis for the standardization of flow measurement throttling devices.

Extended Reading: Sanitary Flow Meters-316SS,Tri clamp-Pulse- for Brewery

The influence of Reynolds number on the vortex flowmeter

The influence of Reynolds number on the vortex flowmeter in a certain range of Reynolds number. Vortex flowmeter output frequency signal with the volume of flow through the measuring tube between the relationship is not affected by the fluid properties (density, viscosity) and components. That is, the flow coefficient is only related to the vortex generator and the shape and size of the pipe.

Therefore, only in a typical medium in the calibration of its flow coefficient and applicable to a variety of media. This is a major advantage of the vortex flowmeter.

However, if the Reynolds number exceeds this range, it will have an impact.

Extended reading: Fluid flow meter types

Vortex flowmeter working principle

In the fluid flow in the pipeline set a vortex generator (resistance fluid). So in the volume downstream of the generator will alternately produce a regular vortex. This vortex is called Kaman vortex street.

The vortex generator is the main component of the detector. It is closely related to the flow characteristics (meter coefficient, linearity, range, etc.) and resistance characteristics (pressure loss) of the meter, and the requirements for it are as follows.

A vortex flowmeter can control the vortex in the direction of the axis of the vortex generator synchronous separation.
In a wide range of Reynolds numbers, there is a stable vortex separation point, maintaining a constant Strohal number.
The ability to produce a strong vortex street with a high signal-to-noise ratio of the signal.
Simple shape and structure, easy processing and standardization of geometric parameters, as well as installation and combination of various detection elements.
materials should meet the requirements of fluid properties, corrosion resistance, abrasion resistance, and resistance to temperature changes.
The inherent frequency is outside the frequency band of the vortex street signal.

Due to strict environmental requirements, some process industries, especially chemical, paper, and water treatment, are all placed under the strict monitoring of the agency. This will drive the vortex flowmeter production increase.

In addition, the privatization of municipal water treatment has become the trend, which will generate new investment to update the aging water treatment and sewer systems.

Multi-variable vortex flowmeters, which can measure temperature and pressure in addition to flow, are also in commercial use. Although its output is negligible, growth can be expected throughout the forecast period.

This enhanced measurement capability allows users to purchase fewer meters, requiring fewer process measurement points and thus fewer potential leak paths.

Read more about: How Vortex Flow Meter measure efficiently? For steam, gas, liquid 

Read more about: Coriolis Mass Flowmeter Working Principle

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Sino-Inst, Manufacturer for Vortex Flow Meters, like gas vortex flow meter, liquid vortex flow meter, sanitary vortex flow meter, insertion vortex flow meter, steam vortex flow meter, and natural gas vortex flow meter.

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

Technical Guide – Thermal mass flow meter

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What is a Thermal Mass Flow Meter ?

The thermal mass flow meter is also called Thermal mass flow sensors, or thermal gas flow meters. The thermal mass flow meter is a meter that uses the principle of heat transfer to detect flow.

That is, the measurement is performed based on the heat exchange relationship between the flowing fluid and the heat source (the object heated outside the fluid or the heating body outside the measuring tube).

The main measurement gas. Thermal gas mass flow meters are mainly divided into two categories, namely: thermally distributed and immersed (or plug-in).

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Thermal mass flow meter working principle

Thermal gas mass flow meter is designed on the basis of thermal dispersion. And adopts method of constant differential temperature to measuring gas flow. It has advantages of small size, easy installation, high reliability and high accuracy, etc.

The meter contains two platinum resistance temperature sensors. The thermal principle operates by monitoring the cooling effect of a gas stream as it passes over a heated sensor. Gas flowing through the sensing section passes over two sensors. One of which is used conventionally as a temperature sensor, whilst the other is used as a heater. The temperature sensor monitors the actual process values whilst the heater is maintained at a constant differential temperature above this by varying the power consumed by the sensor. The greater the gas velocity, the greater the cooling effect and power required to maintain the differential temperature. The measured heater power is therefore a measure of the gas mass flow rate.

The format of gas velocity and power is shown as below:

Where:

  • ρg is the specific gravity of the medium
  • V is velocity
  • K is the balance coefficient
  • Q is heater power
  • Δ T is a differential temperature
  • The medium temperature range of the meter is -40℃～220℃.

In the format (1), the specific gravity of medium is related to the density:

Where:

  • ρg is the medium density in working condition（kg/m3）
  • ρn is the medium density in standard condition, 101.325kPa, and 20℃ （kg/m3）
  • P is the pressure in working condition（kPa）
  • T is the temperature in working condition （℃）

In the formats (1) and (2), there is a certain functional relationship between the velocity and pressure in working condition, medium density, the temperature in working condition.

Due to the sensor temperature is always 30℃ higher than the medium temperature (environment temperature), and the meter adopts the method of constant differential temperature, therefore the meter do not need to do temperature and pressure compensation in principle.

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Know more about How Thermal Mass Flow Meter Technology Works?

Video source: https://www.youtube.com/watch?v=YfQSf2NBGqc

Thermal mass flow meter applications

The thermal measuring principle is widespread in the industry, and is being used successfully in many applications with gas flow, for example:

  • Oxygen, nitrogen, hydrogen, chlorine, and multi-component gas measurement.
  • Blast furnace gas and coke oven gas measurement.
  • Flue gas measurement.
  • Aeration and chlorine measurement in biogas and water treatment.
  • Compressed air measurement.
  • Gas flow measurement for natural gas, liquefied gas, flame gas, etc.
  • Primary air and secondary airflow measurement of power plant blast furnace
  • Flow measurement of underground ventilation or exhaust system

Further reading: Industrial LPG/Propane flow meter

Generally, Thermal mass flow meters produced in China are used to measure gas mass flow.

If you need to measure liquid mass flow. Please contact our sales engineer. We will provide you with detailed product recommendations.

Extended reading: Liquid Mass Flow Meter

Due to the continuous demand for energy due to the development of industrial automation. Natural gas as an energy source is used because of its green environmental protection and economic benefits. The metering of natural gas is very important.

The flow measurement of natural gas is divided into volume flow and mass flow. We mainly introduce the application of thermal gas mass flowmeter in natural measurement.

The main component of natural gas is methane, which contains relatively high molecular weight alkanes (mainly ethane. Natural gas is an explosive and flammable mixed gas. Some natural gas contains toxic sulfides, so the level of safety measurement requirements is high.

Natural gas is measured in the United States using normal cubic meters (corresponding to 101.325 kPa, zero degrees Celsius as the standard) standard cubic feet (corresponding to 14.73 psia, 60 degrees Fahrenheit as the standard.) Commercial natural gas has a combustion calorific value of approximately 10.8 kWh per normal state Cubic meters or 1000 BTU per standard cubic foot. Changes in its gas composition will cause changes in calorific value.

The requirements for the flowmeter thermal gas mass flowmeter during the measurement process:

  1. The mass flow can be measured directly without temperature and pressure compensation.
  2. Understanding the precise gas composition is the main parameter that determines the energy content.
  3. Maintain long-term measurement accuracy
  4. High-precision measurement can be restored by simply cleaning the probe
  5. Low flow rate, low flow rate, high sensitivity signal

Read more about: Natural Gas Flow Meter Selection Guide

Thermal mass flow meter advantages

  1. No need for temperature and pressure compensation for gas flow measurement. Convenient and accurate measurement;
  2. Wide range ratio, can be used for gas leak detection;
  3. Measuring flow rate range: 0.1Nm/s～100Nm/s.
  4. Good seismic performance and long service life, free from the influence of vibration on measurement accuracy;
  5. Overall digital circuit measurement, accurate measurement and convenient maintenance;
  6. Using RS-485 communication, factory automation and integration can be realized. click for inqueries
  7. No pressure loss, suitable for pipes of any shape with known cross-sectional area.
  8. Corrosion-resistant sensor, suitable for measuring corrosive gas.
  9. It is especially suitable for large-caliber measurement to ensure the accuracy of measurement and is suitable for trade settlement.
  10. The amount of construction is very small. Due to the plug-in structure, it can be installed and maintained online.
  11. The base-type instrument can display on-site and control with alarm.

Thermal mass flow meter disadvantages

  1. The thermal mass flow meter responds slowly.
  2. Places where the measured gas composition changes greatly. Due to changes in the cp value and thermal conductivity, the measured value will vary greatly and cause errors.
  3. For small flow, the meter will bring considerable heat to the gas to be measured. 　
  4. For thermally distributed thermal gas mass flow meters, if the measured gas deposits a scale layer on the pipe wall, the measured value will be affected. Must be cleaned regularly. The thin tube type instrument has the disadvantage of being easy to be blocked, and it cannot be used under normal circumstances.
  5. The use of pulsating flow will be restricted.
  6. Thermal mass flow meters for liquids are also restricted in the use of viscous liquids.

Read more about: Benefits Of Digital Gas Mass Flow Meters

Extended reading:
What is the K-factor in a flow meter?
Cryogenic Flow Meters|Liquid Nitrogen-Liquid Oxygen-LNG fluids

FAQ

Thermal mass flowmeters can be divided into contact and non-contact types according to different heat sources and temperature measurement methods.

1. Contact thermal mass flow meter

The heating element and temperature measuring element of this mass flowmeter are placed in the pipe of the fluid to be measured. In direct contact with the fluid, it is often called Thomas flowmeter. It is suitable for measuring the larger mass flow of gas. Due to heating and measuring elements Direct contact with the measured fluid, so the components are susceptible to fluid corrosion and wear. It affects the measurement sensitivity and service life of the instrument. It is not suitable for measuring high flow rate and corrosive fluid, which is the shortcoming of contact type.

2. Non-contact thermal mass flow meter

The heating and temperature measuring components of this flowmeter are all placed outside the fluid pipeline. They do not directly contact the measured fluid. Overcoming the shortcomings of contact.

Extended reading: Gas mass flow controller working principle

Mass flow rate refers to the flow rate of fluid quantity expressed by mass.
The mass flow rate can be expressed by the formula: qm=m/t=ρ×u×A.
In the formula, QM is the mass flow rate, kg/s.
m is the unit fluid mass, kg.
ρ is the fluid density, kg/m3.
t is the unit time, s.
u is the average flow velocity in the pipe, m/s.
A is the cross-sectional area of ​​the pipeline, m2.

Extended reading: U-series Liquid Mass Flow Meter | Liquid-slurry flow measure

Read more about: Coriolis Mass Flowmeter Working Principle

Mass flow rate vs Volumetric flow rate is what we must use in flow measurement and control. In this post, we compare the concept of volume flow and mass flow and the conversion between the two.

Commonly used flow meters, such as orifice plates. Turbine flowmeter. Vortex flowmeter. Electromagnetic Flowmeter. Rotameter. The flow measurement value of ultrasonic flowmeter and oval gear flowmeter is the volume flow of fluid. Coriolis mass flow meters and thermal gas mass flow meters measure mass flow.

Read more about: New Guide: Mass Flow Rate vs Volumetric Flow Rate

The gas mass flow controller is based on the principle of thermal mass flow measurement. With control valve. The Micro Gas Flow Controller (MFC) is used to precisely measure and control the mass flow of gas.

Read more about: Gas mass flow controller working principle

Air mass flow meter VS Controller

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Sino-Inst offer over 10 Thermal Mass Flow Meters, with Best Price.

A wide variety of Thermal Mass Flow Meters options are available to you, such as free samples, paid samples. All of our flow meters can work with the AMS NEW TREX. About 13% of these are magnetic flow meter. 14% are Insertion Magnetic Flow Meter. 25% are Venturi flow meter. 13% are Handheld ultrasonic flow meter, and others are Liquid Turbine Flow Meters.

Sino-Inst is Thermal Mass Flow Meter suppliers, located in China. Mass flow meter products are most popular in North America, Mid East, and Eastern Europe.

The United States, and India, which export 99%, 1%, and 1% of Thermal Mass Flow Meter respectively.

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

Beginner’s Guide: Variable Area flow meter

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What is a variable area flow meter?

Variable area flow meters are flow meters in which the fluid must pass through a restricted area. Because the flow cross-sectional area of ​​the flow meter varies with the height of the float. Therefore, this type of flowmeter is called variable area flowmeter or equal pressure drop flowmeter. The typical instrument of this type of flowmeter is a rotameter. This is in contrast to flow meters such as orifice plates and venturi tubes, where the area of ​​the flow element remains fixed. Variable area flowmeters can measure of gas and fluid flow.

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Variable area flow meter principle

The principle of the variable area flowmeter is to keep the pressure drop constant and use the change of the throttle area to measure the flow rate. It consists of a tapered tube gradually expanding from bottom to top and a rotor or float placed in the tapered tube.

When the fluid flows through the tapered tube, the float in the tube is pushed up to a height corresponding to the flow rate and floats.

When the flow rate increases, the impulse acting on the rotor increases. Because the weight of the rotor in the fluid is constant. The rotor rises. The corresponding annular gap between the rotor and the tapered tube is also increased. The flow rate of the fluid flowing through the annulus decreases. Impulse is also reduced. Bring the rotor to balance in the new position. According to the float position of the rotor, the instantaneous flow value can be measured.

The advantages of area flow meters are simple structure, easy testing, and suitable for measuring small flow rates.

Its disadvantage is that it is easily affected by factors such as fluid density, pressure and viscosity. When testing the flue gas flow, because the flue gas contains dust, the area flowmeter cannot be used.

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Variable area flow meter advantages and disadvantages

  • The advantages of the variable area flow meter are simple structure and easy testing, suitable for measuring small flow.
  • The disadvantage of variable area flow meter is that it is easily affected by factors such as fluid density, pressure, and viscosity. When testing the flue gas flow, because the flue gas contains dust, the area flowmeter cannot be used.

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Variable area flow meter types

We can classify according to different product materials. Including the following categories:

Plastic variable area flow meter

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.

Glass variable area flow meter

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: Fluid flow meter types

Metal variable area flow meter

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, and is especially suitable for medium flow measurement with low flow velocity and small flow.

The metal float flowmeter has local display type and 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, etc. form. Provide users with a very wide choice of space.

Read more about: What is a Flow Meter? Types and how does it work?

Variable area flow meter applications

Because Variable area flow meter has the advantages of simple mechanical structure, convenient processing, stable work, high reliability and low pressure loss. Especially it can measure the characteristics of low Reynolds book small flow medium. Therefore, it is widely used in gas and liquid flow measurement and automatic control systems.

  1. It is suitable for the measurement of small-caliber and low-velocity gas, liquid and steam flow.
  2. Affected by a certain viscosity, it is not suitable to measure high-viscosity media
  3. When the flow rate exceeds 100m3/h, the pressure loss is large.
    Mostly used for process control instruments, the best accuracy is 1%, generally 1.5%, and the range ratio is 10:1
  4. It is not suitable for measuring medium with large density change. It is not suitable to measure the flow of pulsating medium (such as metering pump outlet).

To put it bluntly, even under the conditions of small flow rate, small diameter, low flow rate, low viscosity medium, and no magnetic coupling influence, the variable area flow meter is the best to use.

In addition, the installation of a Variable area flow meter is also very particular. For flow accuracy requirements too high, it is not suitable to use this flow meter!

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

Extended reading: non contact flow meter

Horizontal variable area flow meter

There are two installation directions for variable area flow meter: horizontal installation and vertical installation.

Horizontal installation is divided into left in and out, right in and out.

Vertical installation is divided into top in and bottom out, bottom in and top out.

This one is installed horizontally to measure nitrogen. It is purely mechanical to display instantaneous flow rate.

Read More about: What is the difference between rotameter and flowmeter?

Metal tube variable area flow meter

The metal tube variable area flowmeter is our rotameter.

The LZ series Rotameter Flowmeter provided by Sino-Inst adopts a 304/316 stainless steel structure. It can be used to measure the flow of liquid, gas and steam. Especially suitable for low flow velocity and small flow. Flow measurement of high temperature, high pressure, strong corrosion, conductive or non-conductive media.

Extended reading: Micro flow meters for low flow liquids

Vortex Flowmeter VS Rotameter

Vortex flowmeter and rotameter are two different flowmeters. The working conditions and use environments measured by each flowmeter are different. Therefore, the two flowmeters have their own advantages and disadvantages.

Rotameter is also called metal tube rotameter, which uses variable area measurement principle. Suitable for measuring liquid, gas and other measuring media. Its body uses all-metal structure. There are indication type, remote transmission type and explosion-proof type. Rotameter has 4-20mA standard analog quantity signal output and on-site indication. Especially its body is pointer type. This big advantage can be measured even without power. Widely used in power generation, pharmaceuticals, water treatment, etc.

Extended Reading: What is difference between rotameter and flow meter

The vortex flowmeter has two measurement types: the basic type and the temperature and pressure compensation integrated type. The basic model only measures a single flow rate. The temperature and pressure compensation type is a flow type that can measure temperature and pressure at the same time. The vortex flowmeter also has many advantages. It has the advantages of small pressure loss, large measuring range, high precision, and because the vortex flowmeter has no moving parts. Therefore, maintenance and installation are very simple.

Extended reading: How does a rotameter work

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Sino-Inst offers over 5 Variable area flow meters, with the Best Price.

A wide variety of Variable area flowmeters options are available to you, such as free samples, paid samples.

Sino-Inst is Variable area flowmeter supplier, located in China.

Variable area flowmeters products are most popular in North America, Mid East, and Eastern Europe.

The United States, and India, which export 99%, 1%, and 1% of Variable area flowmeters respectively.

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

Introduction to Piezoelectric Pressure Sensors

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What is a piezoelectric pressure sensor?

The piezoelectric pressure sensor is a sensor that uses the piezoelectric effect of piezoelectric materials to convert the measured pressure into an electrical signal. Use electrical components and other machinery to convert the pressure to be measured into electricity. Measuring precision instrument for related measurement work. Such as pressure transmitters and pressure sensors.

RFQ
More Pressure Sensors

Piezoelectric pressure sensor working principle

Piezoelectric pressure sensors are mainly based on the piezoelectric effect (Piezoelectric effect). Use electrical components and other machinery to convert the pressure to be measured into electricity. Then perform measurement precision instruments such as pressure transmitters and pressure sensors.

Piezoelectric sensors can not be used in static measurement. The reason is the electric charge after the action of external force. When the circuit has infinite input resistance, it can be preserved.

But this is not the case.

Therefore, piezoelectric sensors can only be used in dynamic measurements.

Extended reading: Featured Diaphragm Seal Pressure Transmitters

Its main piezoelectric materials are: dihydrogen phosphate, sodium potassium tartrate and quartz. The piezoelectric effect is found on quartz.

When the stress changes, the electric field changes very little, and some other piezoelectric crystals will replace quartz.

Potassium sodium tartrate, it has a large piezoelectric coefficient and piezoelectric sensitivity. However, it can only be used indoors where the humidity and temperature are relatively low.

Dihydrogen phosphate is a kind of artificial crystal. It can be used in high humidity and high temperature environment. Therefore, its application is very wide.

With the development of technology, the piezoelectric effect has also been applied to polycrystals. For example: piezoelectric ceramics, niobate magnesium acid piezoelectric ceramics, niobate series piezoelectric ceramics and barium titanate piezoelectric ceramics, etc. are included.

The sensors based on the piezoelectric effect are electromechanical conversion and self-generation sensors. Its sensitive components are made of piezoelectric materials.

When the piezoelectric material is subjected to an external force, an electric charge will be formed on its surface. The electric charge will be amplified by the charge amplifier, the measuring circuit and the impedance converted. It will be converted into an electrical output proportional to the external force received.

It is used to measure force and non-electrical physical quantities that can be converted into force. For example: acceleration and pressure.

It has many advantages: lighter weight, reliable work, simple structure, high signal-to-noise ratio, high sensitivity and signal bandwidth, etc.

But it also has some shortcomings: some voltage materials are protected from moisture. Therefore, a series of moisture-proof measures need to be taken. And the output current response is relatively poor. Then it is necessary to use a charge amplifier or a high input impedance circuit to make up for this shortcoming. Make the instrument work better.

Extended reading: Silicon Pressure Sensor

Related Products:

Piezoelectric pressure sensor advantages and disadvantages

  1. The advantages are bandwidth, high sensitivity, high signal-to-noise ratio, simple structure, reliable work, and lightweight.
  2. The disadvantage is that some piezoelectric materials need moisture-proof measures. And the output DC response is poor. It is necessary to use a high input impedance circuit or a charge amplifier to overcome this defect.

Extended Reading: Digital Pressure Sensor-RS485

The working principle of 5 common pressure sensors

In addition to the Piezoelectric Pressure Sensors described in this article, there are many pressure transmitters and pressure sensors that can convert pressure into electrical signals.

So how do these pressure transmitters and pressure sensors convert pressure signals into electrical signals? What are the characteristics of different conversion methods?

Here, I have summarized the measurement principles of several common pressure sensors for everyone. hope that it can help us.

Piezoresistive pressure sensors are mainly based on the piezoresistive effect (Piezoresistive effect). The piezoresistive effect is used to describe the resistance change of a material under mechanical stress.

Unlike the piezoelectric effect described above, the piezoresistive effect only produces impedance changes, and does not generate electric charges.

Most metal materials and semiconductor materials have been found to have a piezoresistive effect. Among them, the piezoresistive effect in semiconductor materials is much greater than that in metals.

Extended reading: wireless pressure transmitter working principle

Because silicon is the mainstay of today’s integrated circuits. The application of piezoresistive elements made of silicon becomes very meaningful.

Piezoresistive pressure sensors are generally connected to Wheatstone bridges through lead wires.

Normally, the sensitive core has no applied pressure, and the bridge is in a balanced state (called zero position). When the sensor is pressed, the chip resistance changes, and the bridge will lose balance.

If a constant current or voltage power supply is added to the bridge. The bridge will output a voltage signal corresponding to the pressure. In this way, the resistance change of the sensor is converted into a pressure signal output by the electric bridge.

The bridge detects the change in resistance value, and after amplification, it undergoes voltage and current conversion. Converted into the corresponding current signal. The current signal is compensated by the nonlinear correction loop. That is, a standard output signal of 4-20mA with a linear corresponding relationship between the input voltage is produced.

In order to reduce the influence of temperature changes on the resistance of the core, and improve the measurement accuracy. The pressure sensor adopts temperature compensation measures to maintain a high level of technical indicators such as zero drift, sensitivity, linearity, and stability.

Extended Reading: Electronic Pressure Switch for Air Compressor

The capacitive pressure sensor is a pressure sensor that uses capacitance as a sensitive element to convert the measured pressure into a change in capacitance value.

This kind of pressure sensor generally uses a circular metal film or a metal-plated film as an electrode of the capacitor. When the film deforms under pressure, the capacitance formed between the film and the fixed electrode changes.

The electrical signal that has a certain relationship with the voltage can be output through the measuring circuit.

The capacitive pressure sensor is a capacitive sensor with a variable pole pitch. It can be divided into a single capacitive pressure sensor and a differential capacitive pressure sensor.

Read more about Capacitive pressure transducer.

A variety of sensors that use electromagnetic principles are collectively referred to. They mainly include inductive pressure sensors, Hall pressure sensors, and eddy current pressure sensors.

Extended reading: how to calibrate a pressure transmitter

The working principle of inductive pressure sensors is due to the different magnetic materials and permeability.

When the pressure acts on the diaphragm, the size of the air gap changes, and the change of the air gap affects the change of the inductance of the coil. The processing circuit can convert the change of this inductance into the corresponding signal output. So as to achieve the purpose of measuring pressure.

This kind of pressure sensor can be divided into two types according to the change of the magnetic circuit: variable magnetic resistance and variable magnetic permeability. The advantages of inductive pressure sensors are high sensitivity and large measuring range. The disadvantage is that they cannot be used in high-frequency dynamic environments.

Hall pressure sensors are made based on the Hall effect of certain semiconductor materials.

The Hall effect refers to when a solid conductor is placed in a magnetic field and a current flows through it.

The charge carriers in the conductor are biased to one side by the Lorentz force. Then a voltage (Hall voltage) is generated. The electric field force caused by the voltage will balance the Lorentz force.

Through the polarity of the Hall voltage, it can be confirmed that the current inside the conductor is caused by the movement of negatively charged particles (free electrons).

Eddy current pressure sensor is a pressure sensor based on the eddy current effect.

The eddy current effect is caused by the intersection of a moving magnetic field and a metal conductor, or the intersection of a moving metal conductor and the magnetic field perpendicularly.

In short, it is caused by electromagnetic induction effects. This action creates a current circulating in the conductor.

Extended reading: What is a pressure sensor?

Vibrating wire pressure sensor is a frequency sensitive sensor.

This kind of frequency measurement has the desired high accuracy. Because time and frequency are physical parameters that can be accurately measured. And the frequency signal can ignore the influence of cable resistance, inductance, capacitance and other factors during the transmission process.

At the same time, the vibrating wire pressure sensor also has strong anti-interference ability, small zero drift, good temperature characteristics, simple structure, high resolution, stable performance. It is convenient for data transmission, processing and storage. It is easy to realize the digitalization of the instrument.

Therefore, vibrating wire pressure sensors can also be used as one of the development directions of sensing technology.

Extended reading: Best Price Ceramic Pressure Sensor

What Is Flush Diaphragm Pressure Sensor?

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

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

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

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

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

Ultrasonic water flow meters | Accurate and Easy solution

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The ultrasonic water flow meter is a meter that measures water flow by detecting the effect of water flow on ultrasonic beams (or ultrasonic pulses). The more commonly used methods are the time difference method and the Doppler method.
The time difference method can measure water, seawater, acid and alkali, edible oil, gasoline, alcohol, and other uniform liquids that can transmit and transmit ultrasonic waves.
If it is sewage, which contains impurities, bubbles, etc., an ultrasonic flowmeter based on the principle of the Doppler method is used.

RFQ More water meters

Ultrasonic water flow meter types

According to the measurement principle

  • Time difference method ultrasonic flowmeter;
  • Frequency difference method ultrasonic flowmeter;
  • Phase difference method ultrasonic flowmeter;
  • Doppler ultrasonic flowmeter;
  • Ultrasonic flowmeters for partially full pipes and river channels that combine liquid level measurement and average flow velocity measurement.

According to the way of use

  • Portable ultrasonic flowmeter;
  • Fixed (standard pipe section) ultrasonic flowmeter.

According to the installation method of the transducer

According to whether the transducer is in contact with the fluid

  • Intrusive (contact) ultrasonic flowmeter;
  • Non-invasive (non-contact) ultrasonic flowmeter.

According to the nature of the measured fluid

  • Liquid ultrasonic flowmeter;
  • Gas ultrasonic flowmeter.

According to the number of transducer channels

  • Mono ultrasonic flowmeter;
  • Two-channel ultrasonic flowmeter;
  • Multi-channel ultrasonic flowmeter.

Extended reading: 2 inch Water Flow Meter

Ultrasonic flowmeters use sound waves to determine the velocity of a fluid flowing in a pipe.

At no flow conditions, the frequencies of an ultrasonic wave transmitted into a pipe, and its reflections from the fluid are the same.

Under flowing conditions, the frequency of the reflected wave is different, due to the Doppler effect.

When the fluid moves faster, the frequency shift increases linearly.

The transmitter processes signals from the transmitted wave, and its reflections to determine the flow rate.

You may like: Digital Flow Meters Guide| Liquid and Gas

Generally, an ultrasonic flow meter is the device, that uses ultrasound to measure the velocity of liquid flow, that helps in determining the volume of liquid flow also.

The ultrasonic flow meters are made using the ultrasonic transducers, which are clamped to the external surface of a pipe, to generate the ultrasonic pulses through the pipe.

When the liquid flows inside the pipe, it creates the time difference in the pulses, and these are examined to calculate the accurate flow velocity of the liquid.

There are many advantages of using the ULTRASONIC flow meters which include:

  • The electronics in the ultrasonic flow meter includes ultrasonic flowmeter detector which compensates and adapts to the changes in the profile of the flow, type of the liquid and material of the pipe.
  • A portable ultrasonic flow meter converter can be used as a direct method to determine the flow rates effectively when compared to the other flow systems.
  • Ultrasonic flow meter converter is inexpensive to use and maintain when compared to the other mechanical flow meters as they are no moving parts in these flow meters.
  • Their design is highly sophisticated and they do not obstruct the liquid flow, so they can be used for sanitary, corrosive and abrasive liquids.

These are the advantages of the ultrasonic flow meters and there are many disadvantages of the Ultrasonic flow meter which include:

  • The main disadvantage of the ultrasonic flow meter is the cost. The cost of the flow meter is very high when compared to the other types of mechanical flow meters.
  • The ultrasonic flow meters are sophisticated when compared to the mechanical flow meters, so it needs experts to repair and maintain the flow meters.

These are the advantages and disadvantages of the ultrasonic flow meters.

Extended Reading: Inline Ultrasonic Flow Meter

The accuracy of Ultrasonic water flow meter supplied by Sino-Inst is 1%. Can meet most of the measurement needs.

Extended reading: Industrial VS Residential inline water flow meters

Ultrasonic Clamp-on Flow Meter is composed of an integrated host and external clamp-on sensors. Clamp-on Flow Sensors are available at room temperature and high temperature.

The clamp-on flow meter (Model: 2000) is composed of an integrated host and ultrasonic clamp-on sensor. The clamp-on flow meter is widely used in the online flow measurement of various liquids. Just stick the external clamp sensor on the pipe surface. Compared with the traditional flowmeter, it does not need to cut off the pipe and flow. The installation is convenient and quick, and the non-destructive installation is truly realized.

Clamp on Flow Meter Reference price: USD 470.00/pc

Extended reading: Make Ultrasonic Open Channel Flow Meter Work for You

A handheld Portable ultrasonic flow meter realizes the non-contact measurement of liquid flow. Also often referred to as Portable Clamp-On Ultrasonic Flow Meter for Liquids.

Handheld Portable Ultrasonic Flow Meter ( Model:2000H) has been successfully applied to measurement work in various industries. The measuring range is 20-6000mm (0.5-20 inches). A non-contact measurement method is adopted. Flexible operation and easy to carry. Conductive or non-conductive, corrosive or non-corrosive liquids can be measured. Various fluids: water, pure water, sewage, seawater, chemical fluids, river water, fuel Oil, etc. can be measured.

Handheld Portable Ultrasonic Flow Meter Reference price: USD 470.00/pc

Extended reading: Typical Applications of Handheld Ultrasonic Flow Meter

Extended Reading: Chilled Water Flow Meter

Ultrasonic Gas Flow Meter uses the principle of measuring the transit time of ultrasonic waves in the pipeline. Ultrasonic Gas Flow Meter is an ideal choice for various gas measurements.

The gas ultrasonic flowmeter is suitable for blast furnace gas, converter gas, coke oven gas, mixed gas, gas, compressed air, chlorine, nitrogen and other industrial gases. Suitable for large-caliber gas measurement, suitable for low flow rate, pulsating flow gas measurement. It has the advantages of not being affected by gas components, dirt resistance, fast response, wide range, high precision, good stability, and less maintenance.

Featured Ultrasonic water flow meters

Portable Ultrasonic Flow Meter
Handheld Ultrasonic Flow Meter
Ultrasonic Clamp on Flow Meter
Strap on flow meter X3
Ultrasonic Water Meter for Residential Water
Ultrasonic Insertion Flow Meter
Insertion Ultrasonic Water Flow Meter
Dual Channel Ultrasonic Water Meter
In-Line Ultrasonic Flow Meter
Ultrasonic Open Channel Flowmeter
Multipath Transit Time Ultrasonic Flow Meter
Portable Doppler Flow Meter

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

Why is it more appropriate to use a Doppler ultrasonic flowmeter to detect sewage pipes?

What kind of flow monitoring equipment should you choose for ordinary sewage pipes?

What kind of flow monitoring equipment should we choose for ordinary sewage pipelines?

The electromagnetic flowmeter can only measure the condition of the full tube. Therefore, the measurement result will be unstable when the tube is not full. Because the non-full tube state can be understood as an extreme situation in which a large number of bubbles exist in the measured liquid medium.

There are two situations when the pipe is not filled with liquid. One is that the liquid level is higher than the level of the electrode. The other is lower than the level of the liquid being measured.

When the liquid level in the pipe is higher than the electrode level. If the front and back straight sections of the pipeline are in an ideal state at this time. Generally, the precision data measured by electromagnetic flow is relatively stable. However, because the flow meter liquid contains the gas volume in the pipeline, there is undoubtedly a large measurement error in this measurement state.

When the electrode is higher than the level of the electrode, the electrode is exposed in the air at this time. The measurement circuit is actually in an open state, and the electrode cannot directly contact the liquid. The value and output are in a random state. If the electrode is constantly shaking or full, the electrode will not work normally, and the measurement will not be carried out.

The measurement of the intelligent electromagnetic flowmeter is not only inaccurate, but also damages the electrodes.

However, many sewage pipes are caused by partial pipes. Only when it rains does the tube become full. So what kind of flow measurement method is the most appropriate in such a situation?

At present, the most advanced technology in China is the use of a Doppler ultrasonic flowmeter. Such as rain and sewage pipes. It can accurately monitor the water level, flow rate, flow rate and instantaneous flow rate, cumulative flow rate, water temperature, and other data. It can be refreshed in real-time, and the installation is very simple.

Extended reading: Ultrasonic flow detectors types

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Sino-Inst, Manufacturer for Ultrasonic water flow Meter. It can measure a single sound-conducting liquid medium of DN 15—150mm. It can measure even liquids such as water, seawater, oil, and slurry.

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

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Water Tank Level Sensors for Level Monitoring & Control System

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The water tank level sensor is an integral part of the water level monitoring and control system. They are responsible for real-time detection and feedback of the water level in the water tank. Water tank level sensors, solenoid valves, control boxes, liquid level switches and other accessories can be used to effectively form a water Level Monitoring & Control System. For example, in scenarios such as sewage treatment, drinking water storage and agricultural irrigation, the water pump switch can be automatically adjusted to control the Water intake and drainage to ensure stable water levels. Therefore, selecting an appropriate tank level sensor is a fundamental and critical task for any system that requires accurate water level monitoring.

RFQ

Water Tank Level Monitoring and Control Systems

Water Tank Level Monitoring and Control Systems are a sophisticated set of technical devices used to track and manage water levels in water tanks in real time. Such systems typically include key components such as level sensors, controllers, displays, and actuators (such as pumps or valves).

  • Water Tank Level sensors are the core of the system, responsible for measuring and transmitting water level data. These sensors can be of various types such as float type, pressure type, ultrasonic type, capacitive type, etc., selected according to different application scenarios. They convert water level changes into electrical signals and send them to the controller in real time.
  • The controller is the brain of the system. It receives signals from the sensors and makes judgments based on the preset water level range. For example, when the water level is below the minimum limit, the controller will start the water pump to fill the water. When the water level reaches the maximum limit, the water pump will be stopped or the drainage valve will be opened to avoid overflow.
  • The display provides the operator with an intuitive interface showing current water levels, as well as system status and alarm information. This information helps operators understand whether the system is functioning properly or if manual intervention is required.
  • Finally, actuators, such as pumps and valves, are the actual devices that respond to controller commands and are responsible for physically regulating the flow of water. The system can automatically or manually adjust these mechanisms as needed to maintain water level stability.
Extended reading: Hydrostatic Level Measurement

Therefore, with Water Tank Level Monitoring and Control Systems, automatic management and control of water tank level can be achieved.

When the water level of the water tank drops to the set lower limit water level value, the liquid level controller sends a command to instruct the pump valve to open the water supply.

When the water level reaches the set upper limit water level value, the controller will issue an instruction to instruct the pump valve to close and stop the water supply.

In the same way, if necessary, the liquid level controller can also instruct the water pump or electric valve to perform the opposite operation.

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

Extended Reading: How to Measure Volume of Liquid

Water Tank Level Sensors Types

The water tank level sensor is a key device to ensure the accuracy of water level monitoring. According to their working principles and application environments, they can be mainly divided into the following types:

  • Float level sensor: This is a traditional liquid level sensor that detects water level changes by moving the float up and down. When the water level rises, the float floats up and drives the switch through the mechanical device to control the opening and closing of the water pump or valve. This kind of sensor is suitable for environments with relatively clean water and no large amounts of impurities and chemicals.
  • Pressure level sensor: also called submersible level sensors. This sensor determines the water level by measuring the pressure exerted by the liquid on the sensor. It is suitable for deep water environments such as deep wells and storage tanks, and can work stably under high pressure conditions.
  • Ultrasonic level sensor: An ultrasonic sensor calculates water level height by emitting ultrasonic waves and receiving their echoes. It is suitable for situations that are corrosive or polluting to contact sensors, such as wastewater and chemical storage tanks.
  • Radar water level sensors: Radar water level sensors have absolute advantages in large-range non-contact measurement. Radar Water Level Sensor can be 0.05m～35m ~70m~120m. Commonly used to measure water level monitoring in dams, reservoirs, rivers, etc.
  • Capacitive level Sensors: Capacitive sensors use changes in capacitance to detect fluid levels. They are ideal for level detection of viscous liquids or powdery substances, as these materials may interfere with other types of sensors.
  • Photoelectric level Sensor: Photoelectric sensors determine water level by detecting the obstruction or reflection of light by the liquid. This sensor is suitable for water level monitoring in small containers or cleaning liquids.

Comparison of digital sensors and traditional mechanical sensors:

Digital level sensor: Using advanced electronic technology, it can provide continuous, high-precision water level readings. And it can be seamlessly integrated with computer systems to facilitate remote monitoring and data analysis. They generally have better long-term stability and immunity to interference.

Traditional mechanical level sensors: usually refer to float sensors, which sense water level changes through a simple mechanical structure. Although these sensors are simple and low-cost, they are often less accurate than digital sensors and are susceptible to mechanical wear and water quality.

When selecting a water tank level sensor, it is important to select the most appropriate type based on factors such as the actual application environment, accuracy requirements, and whether remote monitoring is required.

Extended reading: Industrial Tank level indicators and Tank Level Gauges

We, Sino-Inst, are a professional manufacturer of Water Tank Level Sensors. Provide users with more than 50 types of Water Tank Level Sensors and switches.

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SI-151 Hydrostatic Level Sensor
Radar Water Level Sensor 0.05m～35m ~70m~120m
SI-PCM261 Submersible Pressure Transducer
SI-PCM260 Deep Well Water Level Sensor
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Differential pressure(DP) level transmitter
SI-U02 Multi-Point Liquid Level Float Switch
SI-U01 Float Level Sensor
LT series Digital Display Magnetostrictive liquid level sensor
ULT-100A Ultrasonic Level Transducer
ULT-200 Ultrasonic Level Detector
SI-U03 Float Switch Water Level Controller

PLC liquid level display alarm

Programmable Logic Controller, PLC for short. A digital electronic device with a microprocessor. A digital logic controller used for automatic control. Control instructions can be loaded into the memory for storage and operation at any time.

The programmable controller is modularized by internal CPU, instruction and data memory, input and output unit, power supply module, digital-analog, and other units.

PLC can receive (input) and send (output) many types of electrical or electronic signals. And use them to control or supervise almost all types of mechanical and electrical systems.

Extended reading: ultrasonic level sensor for diesel tank

Program through the PLC system to realize the automatic level control system. It is composed of hardware and software. The hardware mainly includes PLC touch screens and related modules such as CPU, storage, output and input, power supply. On-site measurement includes various types of adaptation to different sites Conditional sensors, switches, etc. Also include sound and light warning lights, control buttons, and other related equipment.

By configuring the PLC liquid level display alarm device, it can realize the display of industrial site liquid level measurement, high and low liquid level alarms. As well as the opening and closing of pumps, valves, and other equipment. Unattended automatic workflow can be realized. Greatly improve production The efficiency, saving human cost. This brings about an increase in corporate benefits. It lays the foundation for the company to take the lead in severe competition in the future.

Therefore, in the current situation, whether it is a newly established project or a modified project, it is recommended that PLC equipment is the first choice when conditions permit.

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

Extended Reading: How many types of level transmitters are there?

Wireless water tank level sensor-Future Trends

Wireless GPRS liquid level alarm device, can be configured with eight channel alarm device, liquid level display alarm device, LED display. It can support liquid level meter switch, float level switch, pressure transmitter, thermocouple, thermal resistance, voltage, Current and transmitter input. Suitable for monitoring of industrial process quantities such as temperature, pressure, flow, and liquid level.

Extended Reading: 3 inch (3″) Water Meter

Construction-free installation: It can replace the connecting cable, and the transmission distance is long, eliminating the trouble of cable construction.

Support 8-channel alarm function, power supply 220VAC or 24VDC switching power supply. For explosion-proof occasions, explosion-proof sensors and explosion-proof instrument boxes can be used.

On-site measurement end. Configuration:

  1. 　Level gauge (can be equipped with level gauge, pressure gauge, temperature gauge)
  2. 　Signal acquisition instrument meter box (common type and explosion-proof type are optional)
  3. 　The switch quantity acquisition module is included in the instrument box
  4. 　DTU module in the instrument box

Extended reading: Ultrasonic Level Switch-External Mounted

FAQ

The function of the liquid level sensor is to detect the liquid level. The liquid level sensor is widely used in electrical appliances and industrial equipment that require water level control. The liquid level sensor can realize the function of water shortage protection.

Principle of water level sensor:
The water level sensor has a sensor. Transform the sensed water level signal into a current signal.

There are many types of water level sensors, so their specific measurement principles are different.
If you need to learn more. You can refer to:
Differential pressure type liquid level measuring instrument;
Float level measuring instrument;
Electric liquid level measuring instrument;
Ultrasonic liquid level measuring instrument;
Radar liquid level measuring instruments, etc.

Extended reading: Capacitive water level sensor

According to the situation of the tank, different types of water level sensors can be selected to monitor the water level of the water tank. Such as static pressure type liquid level sensor. It can be digitally displayed locally and the liquid level value can be displayed. It can also be output by a 4-20mA signal. Connect the signal to the secondary display instrument to monitor the level of the water tank.

Extended reading: Radar Non Contact Water Level Sensor

Extended reading: Radar Water Level Sensor Applications

Common water level sensors can be used for water level control. There are also sensors that can output switching signals, such as float level switches, and can also be used for water level control.

Extended reading: PID Controller Working Principle

The liquid level switch, as the name implies, is a switch used to control the liquid level. In terms of form, it is mainly divided into contact type and non-contact type.

Non-contact type such as capacitive liquid level switch.

Contact type such as: float type liquid level switch, electrode type liquid level switch, electronic liquid level switch.

The capacitive liquid level switch can also be realized by a contact method.

Extended reading: Float Switch Water Level Controller

Installing a tank level sensor is a process that requires precision and care. Specific installation steps may vary depending on sensor model and functionality, so be sure to carefully read the manufacturer’s operating manual and installation guide before installation. If necessary, consult a professional or contact the manufacturer’s technical support. Here are the basic steps and recommendations for installing a water tank level sensor:

Determine the installation location:
For float sensors, choose a location inside the tank that is not disturbed by the incoming and outgoing water flows.
For ultrasonic or capacitive sensors, the top center position of the water tank should be selected to ensure that there is a certain vertical distance between the sensor and the water surface (usually at least 30cm).

Install fixtures:
Depending on the sensor type and tank material, install the fixing bracket or mounting plate.
Make sure all fixings are securely attached to the tank to prevent the sensor from moving or falling off.

Connect power and output:
Connect the power and signal cables (e.g. 2-wire 4-20mA) according to the instructions provided by the manufacturer.
If the sensor has special power requirements (such as DC24V), please make sure the power adapter meets the requirements.

Debug the sensor:
Turn on the power and follow the instructions for preliminary settings and calibration.
For sensors that require calibration, a standard water level can be used to set upper and lower thresholds.

Check system operation:
Check that the sensor accurately reflects changes in water level.
Make sure there is no water leakage at all connections and the signal output is stable.

How to choose right Water Tank Level Sensor for your System

When selecting a tank level sensor and monitoring system, you need to consider the following specific recommendations and reference values:

Application Environment:

  • Water quality: If the water contains corrosive chemicals, sensors made of corrosion-resistant materials should be selected.
  • Temperature: Make sure the sensor’s operating temperature range covers your application environment, such as -20°C to 80°C. If 80°C~150°C, you can refer to high temperature level sensors.
  • Pressure: If used in deep wells, the sensor should be able to withstand a pressure of at least 2MPa.

Accuracy requirements:

  • If the water level needs to be accurately controlled (error range ±1mm), high-precision sensors such as ultrasonic or capacitive sensors should be used.
  • For general agricultural irrigation systems, the error range can be relaxed to ±5mm.

Installation and maintenance:

  • Choose a sensor that is easy to install and configured with appropriate mounting dimensions. Such as threads, flanges, clamps, etc.
  • Maintenance frequency: Choose sensors with high reliability (such as MTBF (mean time between failures) greater than 100,000 hours) to reduce the number of maintenance times.

Ease of use:

The user interface should have clear numerical or graphical displays to ensure easy operation.

Integration and Compatibility:

Choose sensors that support standard signal output and communication protocols (such as 4-20 mA, 0-10V, Modbus, etc.) to ensure compatibility with remote monitoring systems.

Budget and Cost Effectiveness:

  • Calculate the total cost of ownership, including purchase, installation, scheduled maintenance and potential breakdown repairs.
  • Consider sensors with energy-saving features, such as low-energy designs (power consumption less than 0.5W) to reduce operating costs.

Supplier technical support and services:

Choose sensors that offer at least a one-year warranty, and make sure the supplier has service points in the country for quick response.

By considering the specific recommendations and reference values above, you can select a tank level sensor and monitoring system that meets your technical requirements while being cost-effective.

More level monitoring solution

Extended reading: Fuel-Diesel-Water Tank Level Sensor Monitoring

When choosing a suitable water tank level sensor and monitoring system, we must consider a variety of factors, such as application environment, accuracy requirements, ease of installation and maintenance, and budget.

At the same time, we also provide other types of measuring instruments, such as wastewater flow measurement, liquid level measurement and pressure measurement equipment. These high-quality instruments can help you build a more comprehensive monitoring system.

Our Sino-Inst offers over 20 Water Tank Level Sensors for level measurement. About 50% of these are liquid level meters, 40% is the tank level sensor. A wide variety of Water Tank Level Sensors options are available to you, such as free samples, paid samples.

We offer a variety of measurement solutions and support customization to meet your specific needs. If you need professional advice or customized services, please contact us!

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