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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.

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Static pressure vs dynamic pressure vs total pressure

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. The measurement of static pressure is a critical aspect of many engineering applications, particularly in HVAC systems where it helps ensure proper airflow and system efficiency.
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 (pd/Dp).

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 Dp, and is positive. The dynamic pressure of a fluid is directly related to its velocity and can be calculated as 0.5×ρ×v20.5 \times \rho \times v^20.5×ρ×v2, where ρ\rhoρ is the fluid density and vvv is the flow velocity.
pd = 0.5 * air density * wind speed².


q=21​ρv2

Total pressure (Pq).

What is total pressure?

Total pressure is the algebraic sum of the static and dynamic pressures: Pq=Pi+Pb. The total pressure also includes stagnation pressure, which is the pressure when a fluid’s velocity is reduced to zero, and it reflects the combined energy from both static and dynamic pressures.

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.

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Extended reading: Pressure Sensor Applications-Featured Industry Applications

The difference between static pressure, dynamic pressure and total pressure

In HVAC systems, controlling both static and dynamic pressures is essential for proper airflow and comfort in building environments. Proper measurement and management of these pressures ensure that air distribution is both effective and energy-efficient.

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

q = 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)

q=dynamic pressure

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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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)

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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.

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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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Extended reading: Gas Rotameter Tips

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

Related Products:

Gas Thermal Mass Flow Meter
 Annubar Flow Meter
Integral DP Flow Meter
Precession Vortex Gas Flowmeter
Vortex Shedding Flow Meter
Digital air flow meters

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Read more about: Flow Meter Selection Guide

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

You may like:

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.

Featured Water Tank Level Sensors

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
Remote Seal Differential Pressure Transmitter
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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What Is an Air Pressure Transducer?

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An Air pressure transducer is a sensor that converts the mechanical signal of air pressure into a current signal. Pressure has a linear relationship with voltage or current, and it is generally proportional. Therefore, the output voltage or current of the transmitter increases as the pressure increases. From this, a relationship between pressure and voltage or current is derived.

RFQ More Pressure Sensor

Featured air pressure transducers

SI-300 Pressure Transducer 4-20mA/Voltage
The 4-20mA/ Voltage Pressure Transducer,
also called pressure transmitter 4-20mA,
is a pressure sensor with4-20ma/Voltage output.
SI-390 Industrial Pressure Transmitter
Pressure transmitters for general industrial applicaitons. -0.1kPa ~ 0 ~ 0.01kPa ~ 100MPa ~150MPa. 0.1% FS, 0.25% FS, 0.5% FS. 4-20mA (2-wire system), 0-5 / 1-5 / 0-10V (3-wire
SI-503K Gas Pressure Sensor
Gas pressure sensor for industrial gas pressure monitoring. Pagoda gas nozzle Φ8. Such sensors are also commonly referred to as wind pressure transmitters, exhaust pressure sensors.
SI-702 High Pressure Sensor
High pressure sensor is pressure transmitter designed for high pressure measure&control. 0 ～ 40MPa… 600MPa. M20 × 1.5, G1 / 2 (others are customized according to requirements)
SI-702S Ultra-High Pressure Senors
Pressure sensor for Ultra high pressure applications. Ultra high pressures up to 15,00MPa. 0-2000MPa to 0-7000MPa (customized).Ball head M20 × 1.5, cone head M20 × 1.5.
SI-512H High Temperature Pressure Sensor
High Temperature Pressure Sensor for pressure measurement of high temperature gas or liquid. Such as steam pressure. High temperature up to 800 ℃.
SIJC-1000HSM-Silicon Pressure Sensor
Silicon pressure sensor, also known as Diffused silicon pressure sensor. Silicon pressure sensors are low cost.
SI-706 Combined Pressure and Temperature Sensor-Dual function
Combined pressure and temperature sensor for Simultaneous measurement of pressure and temperature.
Thermocouple types: J, K, E type or PT100 platinum resistance. Two outputs do not affect each other. 
Absolute Pressure Transmitter
Absolute pressure transmitter with 4-20mA output for measuring pressure with absolute type reference. Absolute pressure (AP) transmitter is a measure of the ideal (complete) vacuum pressure.
Hydrostatic pressure transmitter
Hydrostatic pressure transmitter is used for fluid hydrostatic pressure measurement. With working static pressure up to 32Mpa, for liquid, gas or steam .

Pressure transducer is a high-precision instrument that can perform on-site inspection of pressure parameters, and is widely used in industrial measurement and control processes. It can be used to measure the pressure, differential pressure and absolute pressure of various media such as liquid, gas and steam. Then the pressure signal is converted into 4-20mADC signal output to supply secondary instruments such as indicating alarm, recorder, regulator, etc. for measurement, indication and process adjustment.

Extended reading: extrusion melt pressure transducer

The functional principle of a resistive pressure transmitter is very simple. The pressure sensor converts the mechanical pressure value into a proportional electrical signal. The pressure sensor typically consists of a stable main body and a (thin) diaphragm.

The diaphragm is the most important element for the measurement of pressure and is equipped with strain-sensitive and compression-sensitive resistance structures, so-called strain gauges (DMS). The diaphragm is deflected under the influence of pressure. 

Thus, the strain gauges attached to it are elongated or compressed and its electrical resistance changes. This change in resistance is directly proportional to the pressure.  For example, if the resistors are wired to a Wheatstone measuring bridge, the resulting electrical signal can be measured and transferred to an indicator.

Extended reading: Pressure indicator transmitters

Read more about: What is a pressure sensor and how it works? 

There are different types of pressure transducers based on their design.

These sensors can come in several shapes and sizes, but the technology inside can also differ. 

There 4 main types of pressure sensors based on this: 

  • Strain Gauge Pressure Transducers
  • Capacitance Pressure Transducers
  • Potentiometric Pressure Transducers
  • Resonant Wire Pressure Transducers

More about Industrial Pressure Sensors

Extended Reading: Electronic Pressure Switch for Air Compressor

The terms pressure sensor, pressure transducer and pressure transmitter are often used interchangeably. We usually define relevant measurement parameters and output signals to distinguish products.

Of course, if you want to strictly distinguish these three words from a technical point of view, you can refer to the following brief introduction:

PRESSURE SENSOR

Millivolt (mV) output signal (also a general term for all pressure types); a device that measures pressure.

The millivolt output signal can typically be used ten (10) to (20) feet away from the electronics without significant signal loss. The signal is proportional to the supply. A 5VDC supply with a 10mV/V output signal produces a 0-50mV output signal.

Older technologies such as bonded foil strain gage or thin film technology produce 2-3mV/V (millivolts per volt), whereas MEMS technology can produce 20mV/V reliably.

Millivolt output signals give the design engineer the flexibility to condition the output signal as their system needs it and can reduce package size and cost.

Extended Reading: 4-20ma pressure transducer wiring diagram

PRESSURE TRANSDUCER

High level voltage or frequency output signal including 0.5 to 4.5V ratiometric (output signal is proportional to the supply), 1-5V and 1-6kHz. These output signals should be used within twenty (20) feet of the electronics.

Voltage output signals can offer low current consumption for remote battery operated equipment such as wellhead SCADA systems.

Supply voltages are typically from 8-28VDC, except for the 0.5-4.5V output, which requires a 5VDC regulated supply.

Older voltage output signals, such as 0-5V, do not have a “live zero” where there is signal when the sensor is at zero pressure. The risk is that the system does not know the difference between a failed sensor with no output and zero pressure.

Extended Reading: Smart pressure transmitter

PRESSURE TRANSMITTER

Current output signal, i.e. 4-20mA (4 to 20mA), the current, rather than the voltage, is measured on the device, rather than the voltage; Sino-Inst pressure transmitters are two wire devices (red for supply, black for the ground).

4-20mA pressure transmitters offer good electrical noise immunity (EMI/RFI), and will need a power supply of 8-28VDC. Because the signal is producing current, it can consume more battery life if operating at full pressure.

Extended reading: Pressure Sensor Applications In Various Industries

Pressure Transducer is a device or device that can sense the pressure signal and convert the pressure signal into a usable output electrical signal according to a certain law. Pressure sensors are usually composed of pressure sensitive elements and signal processing units. According to different test pressure types, pressure sensors can be divided into gauge pressure sensors, differential pressure sensors and absolute pressure sensors.

Pressure sensor is the most commonly used sensor in industrial practice. It is widely used in various industrial automation environments, involving water conservancy and hydropower, railway transportation, intelligent buildings, production automation, aerospace, military, petrochemical, oil wells, electric power, ships, machine tools , pipeline and many other industries, the following briefly introduces some common sensor principles and their applications. Another medical pressure sensor.

Our pressure transmitters can also be upgraded to Low power-battery powered Wireless Pressure Sensors.

The pressure switch adopts high-precision, high-stability pressure sensor and transmission circuit, and then uses the CPU modular signal processing technology to realize the detection, display, alarm and control signal output of the medium pressure signal.

Pressure switches can be widely used in petroleum, chemical, metallurgy, electric power, water supply and other fields to measure and control the gauge pressure and absolute pressure of various gases and liquids. It is an ideal intelligent measurement and control instrument for industrial sites. Pressure switches are widely used in aerospace and military fields, such as M1A1 tanks, Apollo spacecraft, Boeing 747, Airbus A320, F22, F117 and other product manufacturing.

A pressure switch is not the same as a pressure sensor:

(1) The pressure sensor is composed of a pressure-sensitive element and a conversion circuit. It uses the pressure of the measured medium to impregnate the pressure-sensitive element to produce a small changing current or voltage output.
(2) The pressure switch is a utility switch that automatically turns on or off when the set value is reached.

Extended Reading: strain gauge pressure transducer

What is the difference between a pressure switch and a pressure sensor

  1. Difference in function

(1) As the name suggests, the pressure switch is a switch. It is just that the pressure is set in advance. When the measured medium reaches this pressure, the switch can be turned on or off automatically. The pressure switch must be given a pressure value in advance, and then open or close the switch. It is used for simple control, and it is all switching output.

(2) The pressure sensor can not only output analog signals, but also output digital signals. Digital signal processing is more convenient, and it can also be transmitted remotely. The pressure sensor is composed of a pressure-sensitive element and a conversion circuit. The pressure of the measured medium acts on the pressure-sensitive element to generate a small change of current or voltage output.

  1. Price difference

The pressure sensor is naturally much more expensive than the pressure switch. Because the pressure sensor has an internal signal conditioning circuit. Considering the service life and safety, the pressure sensor is much more cost-effective than the pressure switch. The after-sales service, product reputation, The market difference is better than the pressure switch. Obviously, the pressure sensor is still the priority.

  1. Differences in the mode of action

(1) The sensor often needs to be used in conjunction with an external amplifier circuit to complete the process from pressure detection to control and display. Since the pressure sensor is a primary component, the signal fed back by the pressure sensor needs to be processed, analyzed, stored, and controlled through the measurement and control system, so that industrial automation equipment and project operation control are more intelligent.

(2) The pressure switch does not need other cooperation. When the pressure is sensed, it can complete the work independently.

Extended reading: How to calibrate HART pressure transmitters

Air pressure transducer selection:

  1. Measuring range (range)
  2. The output signal, communication protocol, whether with display meter
  3. Process interface (general, please provide thread specifications, flange type, provide specific flange standard, flange size, capillary length, process medium temperature, and other information)
  4. Electrical interface
  5. Installation method (horizontal installation or vertical installation)
  6. Mounting bracket (flat bracket or L-shaped bracket, bracket material requirement: carbon steel or stainless steel)
  7. Other requirements (explosion-proof, explosion-proof, lightning arrester, water, and oil prohibition treatment, etc.)

Read more about Gas Pressure Transducer-Sensor for Gas Pressure Measurement 

Tools for converting and calculating pressure values

Absolute pressure-Gauge pressure ConverterPressure Unit ConverterLiquid Depth/Level to Hydrostatic Pressure Calculator
Differential Pressure CalculatorPressure Transducer 4-20ma Output CalculatorPressure to Liquid Level Calculator

More Pressure Measurement Products

Diaphragm Seal Pressure Transmitter
SI2088-W Wireless Pressure Transmitter
SI-1110 Wireless Pressure Transducer
Differential pressure(DP) level transmitter
SI-151 Hydrostatic Level Sensor
Wireless Level Sensor – LoRa 
Flange Mounted Differential Pressure Transmitter
Extended Diaphragm Seal DP Level Transmitter
Remote Seal Differential Pressure Transmitter
Differential pressure(DP) level transmitter
SI-PCM260 Deep Well Water Level Sensor
SI-302 Anti-corrosive Submersible Level Transmitter

Frequently
Asked
Questions

Help Center

Here we briefly introduce the use of some pressure transmitters;

  1. It is directly used for the measurement of various pressures: air pressure, water pressure, hydraulic pressure (including water pressure), various blood pressure measurement of people in life, etc.;
  2. Pressure sensors are used in automobiles, some high-end motorcycles and almost all internal combustion engines;
  3. Liquid level meter: Most of the field meters used for various liquid level measurement are also pressure sensors;
  4. The source of the weighing signal of most electronic weighing scales and truck scales is also the pressure sensor.
  5. Pressure sensors are also used for acceleration measurement in aviation and aerospace.

There are many others, too many to list.

There are two measurement methods:

  1. Pass the current test of the multimeter, the steps are as follows:
  • The red test lead of the multimeter is connected to the hole of mA, and the black test lead is connected to COM.​​
  • Adjust the gear of the multimeter to the DC mA gear.
  • The red test lead of the multimeter is connected to the positive pole of the 4-20mA sensor output, and the black test lead is connected to the negative pole of the 4-20mA sensor output.
  • Read the reading from the display area of ​​the multimeter, and the reading is the current value.
  1. Through the multimeter’s 10,000-voltage range measurement, for the multimeter without the current test function, the current value can be measured by the voltage, and the steps are as follows:
  • At the output of the 4-20mA sensor, connect a sampling resistor of about 100 ohms.
  • The red test lead of the multimeter is connected to the hole of mA, and the black test lead is connected to COM.​​
  • Adjust the gear of the multimeter to DC V gear.
  • The red test lead of the multimeter is connected to the positive pole of the 4-20mA sensor output, and the black test lead is connected to the negative pole of the 4-20mA sensor output.
  • Read the reading from the display area of ​​the multimeter, the reading is the voltage value, and the current value can be obtained by dividing the reading reading by the resistance value (such as 100 ohms).

Use the DC current function of the multimeter, 20mA gear (if not, choose 100mA gear), and you can directly test the sensor output. If it is a desktop digital multimeter, you can also use any sensor function to allow the instrument to directly test the physical quantity sensed by your sensor. Wiring method: red test lead to green wire, black test lead to yellow wire

The basic principle of the differential pressure transmitter is to divide a space with a sensitive element (multi-purpose bellows) into two chambers. When pressure is introduced into the two chambers, respectively, the sensor produces displacement (or a tendency to displace) under the combined action of the two pressures. This displacement is proportional to the pressure difference (differential pressure) between the two chambers. Convert this displacement into a standard signal output that can reflect the magnitude of the differential pressure.

Read more about: What Is A Differential Pressure Transmitter?

  1. Potentiometer-based calibration
    Some pressure sensors have screws for zero adjustment, span adjustment, or both. Turning these screws will adjust the low end output (zero adjustment) or the high end output (span adjustment).

Typically, these screws are located on the PCB inside the sensor body. If you want to adjust the output, you need to follow these steps:

Turn on the sensor without disconnecting the PCB output port.
Accurately apply zero and full scale pressure to the sensor. (A minimum ±0.1% full scale accuracy of applied pressure is recommended.)
Connect the sensor to appropriate power and monitoring equipment to verify the output of the pressure sensor.
Adjust the zero output first, then adjust the full scale output.
Tools such as DC power supply, multimeter, pressure comparator are required.

  1. Electromagnetic based calibration
    Instead of using potentiometers, some pressure sensors use magnets for decay. Magnet-based calibration comes in two flavors: magnet and shunt calibration (often called shunt calibration).

A small magnet is usually placed near the top or bottom of the pressure sensor to increase or decrease (respectively) the zero output of the pressure sensor. Generally speaking, the full-scale output of this type of sensor can usually only be adjusted by the factory. If you want to adjust, you need to follow the steps below:

Precisely apply zero pressure to the sensor. (We recommend a full-scale accuracy of at least ±0.1% of applied pressure.)
Connect the sensor to appropriate power and monitoring equipment to verify sensor output.
To turn down the zero output, hold the magnet perpendicular to the lower end of the device.
To turn up the zero output, hold the magnet perpendicular to the upper end of the device.
If the zero output is 0 (eg, 0 VDC, 0 mV, etc.), the magnet adjustment of the zero output can be a bit of a hassle. When the zero output is non-zero, on a 1-5 VDC sensor, the actual value is less than the zero output (0.995 VDC, 0.85 VDC), so you can tell when the value is adjusted too far and the output needs to be restored. When the zero output is 0, there is no that extra buffer below the zero output and can be adjusted to a value that can only be pulled back by the factory.

  1. Calibration with software
    It should be easy to adjust the zero and full scale outputs for sensors connected to monitoring software. For example, software that controls a 4-20 mA sensor might have a 4 mA calibration setting and a 20 mA calibration setting. In this way, software control does what shunt calibration and previous calibration techniques do: it adjusts the sensor’s output, as well as controls the device’s reading of the output.

To calibrate a software-controlled sensor, follow these steps:

Connect the sensor to the control software
Accurately apply zero and full scale pressure to the sensor. (A minimum ±0.1% full scale accuracy of applied pressure is recommended.)
Using the software, adjust the zero and full scale output calibration variables until the corresponding output from the sensor is correct.

Pressure sensors are generally divided into two-wire, three-wire, four-wire, and some five-wire systems.

The two-wire system of the pressure sensor is relatively simple, and ordinary users know how to wire it. One is connected to the positive pole of the power supply, and the other wire is connected to the negative pole of the power supply through the meter. This is the simplest.

The three-wire pressure sensor is to add a line on the basis of the two-wire system. This line is directly connected to the negative pole of the power supply, which is more troublesome.

The four-wire pressure sensor has two power input terminals. The other two are signal output terminals. Most of the four-wire systems are voltage outputs. Instead of 4~20mA output. 4~20mA is called pressure transmitter, most of which are two-wire system.

The signal output portion of the pressure sensor is not amplified. The full-scale output is only tens of millivolts. Some sensors have an internal amplifier circuit, and the full-scale output is 0~2V.

For how to connect the display meter, it depends on the range of the meter. If there is a gear suitable for the output signal, you can measure it directly. Otherwise, you need to add a signal conditioning circuit. The five-wire pressure sensor is different from the four-wire type, and there are fewer five-wire pressure sensors on the market.

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

Related pressure measurement solutions

Extended reading: Hydrostatic Pressure Transmitter

Sino-Inst offers over 20 air pressure transducers. A wide variety of air pressure transducer options are available to you. Such as free samples, paid samples. Sino-Instrument is a globally recognized manufacturer of air pressure transducers, located in China.

Sino-Inst sells through a mature distribution network that reaches all 30 countries worldwide. Air pressure transducer products are most popular in Europe, Southeast Asia, and Mid East. You can ensure product safety by selecting certified suppliers. With ISO9001, ISO14001 certification.

Steam Pressure Transmitter

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Steam pressure transmitters are widely used in the measurement and control of various high-temperature steam piping systems. The monitoring of steam pipes is very important. To measure the pressure of steam pipes, have you encountered the following problems:

  • Don’t know which pressure transmitter to choose?
  • Is it good to use a high-temperature pressure transmitter to measure the pressure of the steam pipe?
  • The core of the pressure transmitter removed at the steam site. The diaphragm has been dented by the impact. Is it scrapped directly?
  • How to choose the type and what should be paid attention to when measuring the steam pipeline?
RFQ More Pressure Sensors

Steam pressure transmitter performance

  • The tested medium is widely used. It can test steam, oil, water, and pastes compatible with 316 stainless steel and 304 stainless steel. It has a certain anti-corrosion ability.
  • High accuracy, high stability, use imported original sensors. Good linearity. High temperature resistance and high stability.
  • Small size, light weight, easy to install, debug and use
  • Stainless steel fully enclosed shell, good waterproof.
  • The pressure transmitter directly senses the pressure of the measured liquid level and is not affected by the bubbling and deposition of the medium.
  • The overall performance in the industrial field is ±0.15%, so that the loop performance is optimized
  • Five-year stability ±0.15%, which can greatly reduce the cost of calibration and maintenance
  • Faster dynamic response reduces process variability
  • The introduction of technology can realize a comprehensive measurement plan
  • Local/external: zero/range adjustable

Extended Reading: Smart pressure transmitter

Related Products:

SI-702 High Pressure Sensor
High pressure sensor is pressure transmitter designed for high pressure measure&control. 0 ～ 40MPa… 600MPa. M20 × 1.5, G1 / 2 (others are customized according to requirements)
SI-702S Ultra-High Pressure Senors
Pressure sensor for Ultra high pressure applications. Ultra high pressures up to 15,00MPa. 0-2000MPa to 0-7000MPa (customized).Ball head M20 × 1.5, cone head M20 × 1.5.
SI-512H High Temperature Pressure Sensor
High Temperature Pressure Sensor for pressure measurement of high temperature gas or liquid. Such as steam pressure. High temperature up to 800 ℃.
SIJC-1000HSM-Silicon Pressure Sensor
Silicon pressure sensor, also known as Diffused silicon pressure sensor. Silicon pressure sensors are low cost.
SI-706 Combined Pressure and Temperature Sensor-Dual function
Combined pressure and temperature sensor for Simultaneous measurement of pressure and temperature.
Thermocouple types: J, K, E type or PT100 platinum resistance. Two outputs do not affect each other. 
Cryogenic Pressure Transducer
High Frequency Dynamic Pressure Sensor
SI-338 Ceramic Pressure Sensor
SI-303 Low-Pressure Transducer
SI-350 Sanitary Pressure Transmitter

Extended reading: Featured Diaphragm Seal Pressure Transmitters

Steam pressure transmitter installation

  1. When wiring, pass the cable through the waterproof connector (accessory) or flexible tube and tighten the sealing nut to prevent rainwater from leaking into the transmitter housing through the cable.
  2. Prevent the pressure transmitter from contacting corrosive or overheated media;
  3. When measuring the liquid pressure, the installation position of the transmitter should avoid the impact of the liquid (water hammer phenomenon) to avoid damage to the sensor overpressure;
  4. When measuring the liquid pressure, the pressure port should be opened on the side of the processing pipeline to avoid precipitation and slag;
  5. When measuring gas pressure, the pressure tap should be opened at the top of the process pipeline. The transmitter should also be installed on the upper part of the processing pipeline. So that the accumulated liquid can be easily injected into the processing pipeline;
  6. Prevent dross from depositing in the duct;
  7. When measuring steam or other high-temperature media, a buffer tube (coil) and other condensers should be connected. The working temperature of the pressure transmitter should not exceed the limit;
  8. When freezing occurs in winter, the transmitter installed outdoors must take anti-freezing measures. Avoid volume expansion of the liquid in the pressure inlet due to icing, leading to damage to the sensor;
  9. The pressure guiding tube should be installed in a place with small temperature fluctuations;

Read more about: What is a pressure sensor and how it works? 

What should be paid attention to when measuring the pressure on the steam pipeline?

Pressure transmitters are used for steam metering and pipeline monitoring.

The temperature in the steam pipeline is generally relatively high. The low is more than one hundred degrees Celsius, and the high is two to three hundred degrees Celsius.

The start and stop of the valve will also cause the pressure in the pipeline to fluctuate.

Today we are going to talk to you about what to pay attention to when measuring the pressure of steam pipes?

When measuring the pressure of the steam pipeline, a high-temperature pressure transmitter should be selected due to the high-temperature environment.

In fact, in steam conditions, it only needs to pass through the surface bend (condensation tube). After passing through the elbow, the steam will condense into water at the elbow. Insulate the temperature, so as to achieve a good cooling effect.

The pressure transmitter after passing through the elbow on the pipeline with insulation layer is basically at room temperature. If it is not insulated, the high temperature will rise, causing the temperature of all objects above the pipeline to rise.

Advantages: The use of bends can optimize the cost, and is compatible with the product.

The material selection of a good bend is high. It is thicker and more durable than the general watch bend on the market. Good pressure resistance. The price will be slightly more expensive.

Extended Reading: FMCW Radar for High Temperature Level Sensor

The above-mentioned pressure transmitter diaphragm damage is due to the phenomenon of water hammer.

The valve suddenly opens or closes, causing the pressure in the steam pipe to fluctuate suddenly.

Especially when the valve is opened, huge pressure fluctuations will cause the pipeline to vibrate violently. Even shocking.

The pressure transmitter will also withstand huge pressure in the pipeline. In severe cases, the core may be dented or even burst.

The prevention method is to install safety valves and accumulators, and open and close the valves slowly. Install a trap at the high point of the air discharge valve at the low point.

Some pressure transmitters will be protected by dampers and baffles.

The damper is a copper piece with a 4mm outer wire and a T-shaped thin through-tube structure inside. It can prevent the medium from directly impacting the diaphragm.

The baffle is placed on the front end of the core before assembling the core. Metal plate with holes. It also prevents the medium from directly impacting the diaphragm.

In the hydraulic machinery industry, there are a lot of equipment for pressure transmitters, which are often used for pressure control.

But hydraulic machinery is very prone to pressure shock when it is working. The shock pressure will far exceed the normal pressure, causing damage to the pressure transmitter.

In this case, some pressure transmitters have internal wires and dampers in the standard pressure port. Can effectively alleviate the impact.

The hydraulic and mechanical pressures are all above 10MPa. Generally, the transmitter above 10MPa should be equipped with a damper as standard. If the pressure shock is severe, a baffle can be added to alleviate the shock.

Extended Reading: Electronic Pressure Switch for Air Compressor

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

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Extended Reading: Digital Pressure Sensor-RS485

Sino-Inst offers over 10 Steam Pressure Transmitters. A wide variety of  Steam Pressure Transmitter options are available to you. Such as free samples, paid samples.

Sino-Inst is a globally recognized manufacturer of Steam Pressure Transmitters, located in China. Sino-Inst sells through a mature distribution network that reaches all 30 countries worldwide. Steam Pressure Transmitter products are most popular in Europe, Southeast Asia, and Mid East. You can ensure product safety by selecting certified suppliers. With ISO9001, ISO14001 certification.

How does a residential water meter work?

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What does a residential water meter look like?

A residential water meter is a legal meter for measuring water consumption in residential communities, residential buildings, bungalows, and other places.

What are the commonly used residential water meters? In terms of functions, there are smart IC card water meters, remote water meters, and smart valve-controlled water meters. Below, we will briefly introduce these common and commonly used residential water meters!

RFQ
More meters

Residential Water Meters Types

The types of water meters can be divided by the principle of measurement. The common types are mechanic water meters, mechanical water meters equipped with electronic devices, and electronic water meters.

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

Their working principles are as follows:

Measuring sensors, calculators, and indicating devices are all water meters with mechanical principles and structures. There are mainly speed water meters and volumetric water meters.

Extended reading: Industrial VS Residential inline water flow meters

Keep a mechanical water meter with a complete structure. On this basis, a water meter with an electronic device is installed. There are mainly IC card water meters and remote water meters. The measuring sensor of the mechanical sensor electronic water meter is composed of a sensor based on the principle of mechanical motion and a sensor element that can convert the mechanical motion into an electrical signal and input it into the calculator. Both the calculator and the indicating device are electronic components. Such as vortex (impeller) wheel type electronic water meter.

Extended Reading: 3 inch (3″) Water Meter

Electronic water meters are divided into mechanical sensor electronic water meters and electronic sensor electronic water meters. The measuring sensor of the electronic water meter is based on the principle of electronic or electromagnetic induction. Both the calculator and the indicating device are electronic components. Such as ultrasonic water meter, jet water meter, Coriolis water meter, and electromagnetic water meter.

Extended reading: Advantages and disadvantages of ultrasonic water meters

Read More about: Chemical Flow Meter Guide

Related Products

Extended Reading: LORA water meter

Where is the Residential water meter installed?

In order to be beautiful and save space, water meters are generally installed in their own kitchens. Some of them will be installed in the corner of the kitchen or covered by other kitchen furniture.

However, in order to facilitate the reading of the water meter, it is best to install the water meter in a conspicuous position.

If the house has a special type, it may be installed outdoors.

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

Precautions for installation of Residential water meter

  1. If it is to install a water meter on a new pipeline. You have to rinse all the stolen goods in the pipeline first. This will prevent the water meter from slowing down or not moving in the later stage.
  2. It is better to install a filter before the water meter is installed. Before installing other instruments in the pipeline, the debris in the pipeline should be cleaned up. Avoid clogging of pipes.
  3. When installing, keep the direction on the watch case consistent with the direction of the water flow. And the place where the water meter is installed. The location should be convenient for us to read or change later. The place where the water meter is installed should not be installed in a place exposed to the sun and freezing.
  4. When the water meter is installed, the reading side should be facing up.
  5. The direction of the arrow on the water meter should be the same as the direction of the water flow in the pipe.
  6. If the water meter is installed outdoors, it must be protected against sun and frost. Because the outdoor environment is better than the indoor environment. If the water meter is exposed to the sun or cold for a long time, the service life of the water meter will be affected. If the gear of the water meter is exposed to the sun for a long time. It will cause deformation and damage. This will affect the accuracy of water meter measurement.

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

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Extended Reading: Chilled Water Flow Meter

Sino-Inst offers over 30 residential water meter products.

A wide variety of residential water meter options are available to you, such as free samples, paid samples.

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

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

Sino-Inst sells through a mature distribution network that reaches all 50 states and 30 countries worldwide. residential water meter products are most popular in Domestic Market, Southeast Asia, and Mid East.

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