Pressure is one of the parameters which should be measured and adjusted to make various processes run correctly. It should be measured because of many reasons (process control, continuous monitoring, safety and quality control) in different industrial branches, medical processes, for safe operation of HVAC and refrigerating systems, in aviation, automotive sphere. Besides measuring pressure as a separate physical value, the sensor performs an important function of conversion of this value into an electrical signal (works as transducer). The measurement may be direct (immediate measurement / calculation) and indirect (the physical parameters, the pressure depends on, are measured and then the corresponding pressure value is calculated).
Pressure sensors are used to measure absolute, differential (comparison of pressure at any point to normal) and gauge (related to atmospheric pressure). Depending on the process, that the sensor should be applied for, a correct model should be selected among a big variety of the pressure sensors. Environment, pressure range, required accuracy and frequency levels, medium in which the sensor is applied – all these factors determine what the pressure sensor should be like (capacitive sensor, electrical, inductive, piezoelectric, strain, vibrational, vacuum etc.).