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Differential pressure transmitter

pressure transmitters are essential measuring instruments in modern industrial processes. Designed to measure with precision...

pressure transmitters are essential measuring instruments in modern industrial processes. Designed to accurately measure the pressure difference between two points in a system, these sensors play a key role in process control, flow monitoring, leak detection, and liquid or gas level control. Their ability to provide reliable signals, even for very small pressure differences, makes them indispensable for optimizing the performance, safety, and maintenance of industrial facilities.

At Fuji Electric, our range of differential sensors combines high precision, robustness, and simple integration into your automation systems, while meeting the specific requirements of various sectors such as chemicals, energy, water, and oil and gas.

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Differential pressure transmitter - FKC
ref : FKC
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1385,00 €
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Nuclear analog pressure transmitter - FYC - K3
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Nuclear analog diaphragm seal absolute pressure transmitter - FYD - K3
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Diaphragm seal differential pressure transmitter - FKD
ref : FKD
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Differential pressure transmitter FKC - high static pressure
ref : FKC-HIGH STATIC PRESSURE

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Nuclear differential pressure transmitter - FKC - NC - K3
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Nuclear diaphragm seal differential pressure transmitter - FKD - NC - K3
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Hydrogen pressure transmitter - FKC with hydroseal membrane
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Technologies

Industrial Pressure transmitter ATEX SIL2 SIL3
The pressure transmitter industrial ATEX SIL 2 SIL 3 for liquid, gas and steam. Continuously measures pressure, flow, level and density. Available in ATEX.
Discontinuating producs - Pressure transmitters
Fuji Electric improves its pressure transmitters with the latest technological innovations. Discover our comparative table of old and new references for a simplified transition and optimal performance.

pressure transmitters Buying Guide

The differentialpressure transmitter or deltaP sensor is a device that measures the pressure difference between two points in a system. This type of industrial pressure transmitter can measure very low differential pressures with great precision. A key element in fluid mechanics, the differential pressure sensor is used to regulate and control industrial processes. They can also be used to measure tank levels, or to monitor the flow of liquid or gaseous fluids.

It also detects gas or liquid leaks, identifiesfilter clogging, and helps monitor the performance of motors, pumps and hydraulic systems.

Brochure

pressure transmitters FCX-AIV Fuji Electric

Download the brochure and find out how to improve your measurement accuracy with Fuji Electric differential pressure transmitters .

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Introduction to differential pressure

Differential pressure is a fundamental concept in industrial process control.

It refers to the pressure difference between two points in a system.

This measurement is essential for many applications, including flow measurement, level measurement and filter monitoring.

Differential pressure transmitters are specialized measuring instruments, designed to accurately measure this difference and provide a reliable signal, essential forautomation and process control. By monitoring differential pressure, industries can optimize the performance of their production equipment, guarantee efficient operation and maintain the safety and reliability of their installations.

Whether controlling fluid flow, monitoring filter condition or regulating tank levels, differential pressure measurement is a key lever for achieving high levels of performance and efficiency in many industrial sectors.

What is the principle of the differential pressure transmitter Dp?

Differential pressure (dp) is the difference in pressure between two points.

The differential pressure cell compares two pressures measured between two points:

a reference pressure on the low-pressure side (BP or LP)
pressure on the high-pressure (HP) side

In this way, the differential pressure sensor converts the pressure difference (HP-BP) into a 4-20mA analog signal.

what is the principle of the differential pressure transmitter

Differential pressure transmitter types

Differential pressure transmitters are available in a range of types, each designed to meet specific measurement requirements and a variety of operating environments.

Traditionally mounted transmitters are commonly used for general-purpose applications. On the other hand, diaphragm seal transmitters with an offset diaphragm are ideal for processes involving aggressive or contaminated fluids, as the diaphragm system isolates the sensor from direct contact with the process fluid.

Digital differential pressure transmitters offer enhanced accuracy and advanced features, making them particularly suitable for applications requiring precise control and data integration in automation systems.

The choice of transmitter depends on several factors: nature of the fluid, desired measurement range, environmental conditions, installation constraints or maintenance requirements.

Differential transmitters with electronic display provide a simple, effective solution for direct visual reading of a pressure difference on a single dial. They are widely used in systems requiring fast, reliable local control.

Choosing the right type of differential transmitter ensures accurate measurement and reliable performance in a wide range of industrial applications.

how the pressure transmitter differetielle works

How does pressure transmitter differential work?

The differential pressure sensor has two pressure measurement ports: one for low pressure (BP or LP) and one for high pressure (HP).

Each port is connected to a metal membrane made of stainless steel or another material.

When the differential pressure of the industrial process is applied across each of these ports, it deforms the two membranes.

The capacitivepressure transmitter measures pressure differences by deforming two metal diaphragms.

The metal diaphragms will transmit the measured differential pressure via an internal transmission fluid (oil) to the micro-capacitive electronic chip.

The differential pressure exerted on either side of this element will compress and deform the chip.

The deformation measured is proportional to the differential pressure to be measured.

The signal is then processed digitally by the electronics unit to convert the deformation into an analog 4-20 mA and digital HART signal.

A differential pressure transmitter can display positive or negative values, depending on the direction of the measured pressure. When the pressure on the low side becomes higher than that on the high side, the transmitter indicates a negative value, thus clearly identifying the direction of the pressure difference in the system.

Flow measurement with differential pressure transmitters

Flow measurement is one of the most widespread applications for differential pressure transmitters in industry.

The principle involves creating a pressure drop across a primary element or depressurizer - such as an orifice plate, Venturi tube or Pitot tube - installed in the pipe. As the fluid flows through this restriction, the transmitter measures the pressure difference between upstream and downstream of the primary element.

This pressure difference is directly proportional to the flow rate, enabling precise monitoring and control of process flows.

Pitot tubes are particularly well-suited to measuring flow at a localized point in the pipe, making them useful for applications requiring point-in-time analysis of fluid velocity.

The use of differential pressure transmitters for flow measurement is a reliable and proven method that contributes toprocess optimization, quality control and the efficient operation of production systems.

Level measurement with differential pressure transmitters

Differential pressure transmitters are also widely used for level measurement in tanks and reservoirs.

In this type of application, the transmitter detects the pressure difference between the bottom and top of the tank, a value directly correlated to the liquid level inside. This method is suitable for both open and closed tanks, offering a flexible solution for a wide range of process requirements.

The use of diaphragm seals is particularly recommended for corrosive, viscous or contaminated liquids, as they protect the transmitter while guaranteeing long-lasting measurement accuracy.

By integrating differential pressure transmitters with other process instruments - such as sensors or flowmeters - operators get a coherent, global view of their plant, improving process control and equipment protection, even in the most demanding environments.

what are the applications of differential pressure transmitters ?

What are the applications for differential pressure transmitters ?

The various types of differential pressure transmitters are used in a wide range of industrial applications. These include flow measurement, level measurement, filter clogging measurement and density measurement. They are also used for interface measurement.

These differential pressure probes are widely used in many fields. These include thermal energy, thechemical industry, and theoil and gas industry.

Benefits of pressure transmitters – FCX Series

benefits of the fcx differential pressure transmitter

High-precision pressure transmitters from pressure transmitter manufacturer Fuji Electric measure differential pressure and transmit an electrical signal in the form of a 4-20 mA analog output.

Designed and manufactured in France, the differential transmitters incorporate a patented, reliable, and durable silicon capacitive chip combined with advanced digital signal processing. This combination guarantees exceptional performance in terms of accuracy and stability.

Features such as digital signal processing and flexible mounting options enhance the overall efficiency of the measurement system.

The FCX series pressure transmitters are available in several versions (direct mounting, with diaphragm seals , specific versions for harsh environments or critical applications), enabling them to be used in a wide variety of industrial processes.

This type of industrialpressure transmitter is particularly well suited to applications requiring very high precision, even at very low differential pressures.

ROBUST DESIGN
LOW DIFFERENTIAL PRESSURE
EXTREME TEMPERATURES

Advantages of FCX pressure transmitters

High precision and excellent long-term stability
Patented silicon capacitive chip, overpressure-resistant and reliable
Advanced digital signal processing for optimized response
Robust construction, guaranteed safety
Designed for minimum inventory
Wide measuring range
Flexible mounting options for easy integration into any environment
Quick and easy installation: screwed, threaded or flanged connections, diaphragm seals
Low maintenance, thanks to simple, robust design
Minimal influence of environment and temperature
Greater flexibility for standard use in all your applications and industrial processes
Programmable analog output 4...20 mA linear or square root with digital display
Configurable with tools for pressure transmitter with HART communication protocol
Available as pressure transmitter with diaphragm seals for extreme temperatures from -90 °C to +400 °C
Safety approvals SIL 2 SIL 3 to DIN EN 61508
Explosive atmosphere approvals ATEX, SI, CSA
Version with optional aluminum or stainless steel housing
Power supply: 24 Vdc

differential pressure measurement with separators

Diaphragm seal pressure transmitter

differential level measurement with separators

Differential diaphragm level sensor

level or differential density measurement with pfa-coated separators

Pressure transmitter for level or density measurement with PFA diaphragm seal

FAQ pressure transmitters differential

What is the output signal of a differential pressure transmitter ?

Depending on the application, the 4-20 mA output signal can be programmed either as a linear output (output signal proportional to differential pressure) or as a square-root output (output signal proportional to volume flow).

The square-root output function of a differential pressure transmitter measures the flow velocity of a fluid. This method is commonly used in differential pressure flow measurement systems to determine flow rates in industrial installations.

This principle is based on the relationship between fluid velocity and the differential pressure generated by fluid flow(Bernoulli's law),

Principle of differential pressure flow measurement (Bernoulli's law)

This relationship for differential pressure transmitter flow measurement is expressed by the following equation:

V = sqrt((P1 - P2) / (1/2 * rho))

P1 = High-pressure side pressure (HP) measured upstream of fluid flow

P2 = Low pressure (LP) measured downstream of fluid flow

rho = Fluid density

V = Fluid velocity

What are the pressure ranges of differential pressure transmitters?

A wide range of measurement ranges and differential pressure transmitters references are available. The selection of measurement ranges goes from 0 to 1 mbar for the lowest scales to 0 to 30 bar for the highest scales.

These differential pressure ranges meet the requirements of a wide range ofindustrial applications, ensuring effective monitoring of fluids (liquids, gases, steam) in your industrial processes.

The wide range of differential pressure transmitters available reflects the diversity of market needs.

what are the pressure ranges

What are the advantages of pressure transmitter differential?

Differential pressure transmitters offer many advantages for industrial processes.

Numerous applications: flow measurement, level measurement, filter clogging measurement, density measurement, interface measurement
Robust design withstands very high static pressures
Improved measurement accuracy compared to using two relative pressure transmitters
Low-pressure differential pressure measurement
pressure transmitters with diaphragm seals for extreme temperatures from -90 °C to +400 °C and harsh environments

Why use one differential pressure transmitter rather than two gauge pressure transmitters?

Measuring the pressure difference between two points in a system is simplified by the use of a differential pressure transmitter. This measuring instrument is designed to accurately measure the differential pressure and provide a corresponding digital pressure signal. With a differential pressure transmitter, you can accurately measure the pressure difference without the need for manual calculations.

Another way of measuring differential pressure is to use two gauge pressure transmitters. You then have to measure the pressure separately and manually calculate the pressure difference. This process can be laborious and error-prone.

In addition, if you are using two relativepressure transmitters , it is essential to ensure that each transmitter is accurately calibrated for precise pressure measurements. Indeed, if one of the pressure transmitters is out of phase, the differential pressure measurement may be erroneous.

The use of a pressure transmitter eliminates these problems and the risk of measurement errors. You use a single type of device, specifically designed for this differential pressure measurement application. You get accurate, reliable measurement you can rely on. The commissioning stage of these differential pressure transmitters is simplified by our user guides.

What is the unit of differential pressure?

The unit of measurement for differential pressure is the pascal (Pa).

Other commonly used differential pressure units include bar, millibar and mmCE.

what-is-differential-pressure-unit-en

Control your industrial processes with our differential pressure transmitters , even at very low pressures!

The differential pressure transmitter : an indispensable ally

Discover how our differential pressure transmitters can help you improve flow measurement, level measurement and filter monitoring in your plants. Integrate them into yourindustrial automation systems for real-time control, continuous process optimization and enhanced equipment reliability.
Ideal for the oil & gas, water treatment and chemical industries, this new-generation sensor combines precision, performance and durability.

Our transmitters integrate easily with your supervision software and automated control systems. Conceived with robust materials and optimized design, they meet the ever-changing needs of industrial instrumentation.

Contact our experts to choose the right transmitter for your industrial environment and boost the efficiency of your measurement systems.

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