A pressure transmitter can be divided into two functional components:
– A sensor element that converts the pressure to an electronic signal.
– The transmitter electronics that amplify, convert, and apply signal conditioning such as linearization to the raw sensor signal.
The sensor element measures the pressure with strain gauge measuring technology, a thin sensor membrane will alter shape with the changes in pressure and that can be measured with a Wheatstone bridge on the membrane. A Wheatstone bridge is an electronic circuit whose electronic properties changes proportional to the altering shape of the sensor membrane, and this electronic change can be measured with extreme accuracy. Thus, the signal output from the sensor is proportional to the changes in pressure.
The sensor elements in Trafag’s pressure transmitters are mainly based on two different technologies: thin-film on steel and thick-film on ceramic. Piezoresistive sensors are also common on the market but only used by Trafag in special cases