What is a pressure transmitter working principle

Pressure transmitter: structure and properties

Pressure transmitter or Process transmitter are components that help to convert pneumatic or hydraulic pressure into electrical output signals (current or voltage). They differ from pressure sensors in that the measuring range can be adjusted in the predefined pressure interval. This is known as turndown, scale down or span adjustment.

Synonym (s): process transmitter

Pressure transmitter and process transmitter are synonymous. In the market, pressure sensors or pressure transmitters are often used instead of the term pressure transmitter. Pressure transmitters, however, differ from pressure sensors / pressure transmitters.

The principle of pressure measurement clearly explained.


Pressure transmitters are usually equipped with a digital display, pressure connection, pressure sensors, device electronics (operating software), power supply and housing. The operating software is important for the parameterization. Like pressure sensors, they have electrical and mechanical interfaces and a standardized output signal. Pressure transmitters are designed in such a way that each measuring point can be adapted to a large number of specific requirements and can be implemented individually on site.

Pressure transmitter with SoS technology from the high-performance series from SUCO.


The overall conditions must be right for trouble-free use. In the event of temperature fluctuations, vibrations, shocks or contact with aggressive media, the components of the pressure transmitter can be impaired, damaged or even destroyed. Therefore, in some applications it is better not to mount the device at the measuring point, but rather a little away. The connection can be established via a capillary line. There should be no devices with electromagnetic radiation in the vicinity, as these can also lead to interference.

A span adjustment (turn down) is possible with pressure transmitters. This means that the measuring range is not fixed from the start, but can also be defined or adjusted afterwards. In addition, the zero point and other parameters, such as the measurement offset, can be adapted to the specific application.

The very high measuring accuracy can be additionally increased by calibration or correction programs and the overall error can be minimized. Smart transmitters (intelligent transmitters) can be read out remotely using two-way protocols. This is useful for pressure transmitters that are difficult to reach.


Normal maintenance includes cleaning the device and replacing wear parts (sealing rings). With some types of sensors it can happen that readjustment or recalibration has to be carried out.


One advantage has already been mentioned above: the adjustability of the otherwise fixed measuring range in the pressure interval. Additional advantages:

  • Zero point can be adjusted
  • Parameters in general can be adjusted
  • very high measuring accuracy in the entire measuring range

Areas of application

  • Pneumatics
  • Hydraulics
  • Process technology
  • process technology

In industry, pressure transmitters are used to control and monitor machines and systems. In hydraulics and pneumatics, they are particularly important for determining and regulating the system pressure. As a rule, pressure transmitters are used in the areas mentioned above

  1. Monitoring of critical limit values
  2. Pressure regulation and control
  3. indirect measurement of the process variables

used. Pressure transmitters can be found in everyday life, for example in rail transport or heating systems.


SUCO offers innovative, precise and robust pressure transmitters. The product portfolio includes pressure transmitters with SoS technology and digital CANopen pressure transmitters. In addition to the pressure transmitters, high quality accessories are also offered.
ACS control system
ACS Controlsystem offers pressure transmitters without digital display for measuring relative pressure in liquids, dusts, vapors or gases. The process pressure is between 400 mbar and 1,000 bar.
The pressure transmitters from WIKA impress with their high measuring accuracy, scalable measuring ranges, a selection of housing variants and components made of stainless steel. At WIKA, a distinction is made between universal process transmitters, industrial process transmitters and differential pressure transmitters.
Keller AG
Keller AG offers pressure transmitters in the following versions: standard, flush-mounted, high-temperature, differential pressure transmitters, automotive, intrinsically safe, with pressure-resistant encapsulation, OEM high-pressure transmitters and analog ones.
The pressure transmitters from KROHNE are used to measure absolute, gauge and differential pressure. They offer products from simple, compact pressure transmitters to modularly expandable measuring transducers. The measuring cell is either made of ceramic or metal. The transmitters are used in Ex areas or in hygienic & safety-related applications (SIL).
Huba Control
Huba control offers a wide range of pressure transmitters for different pressure ranges. The Huba Control Transmitters are particularly suitable for the shipbuilding industry.