Pressure sensor is used to measure the pressure of liquids and gases. Similar to other sensors, pressure sensors convert pressure into electrical output when they operate.
Two, pressure sensor classification:
Pressure sensors in the use of technology, design, performance, working conditions and prices have great differences. It is estimated that there are more than 60 pressure sensors of different technologies and at least 300 companies producing pressure sensors worldwide.
Pressure sensors can be classified by the range of pressure they can measure, the operating temperature and the type of pressure; The most important one is the type of pressure. Pressure sensors can be classified into the following five categories according to pressure types:
①, absolute pressure sensor:
This pressure sensor measures the true pressure of the flow body, that is, the pressure relative to the vacuum pressure. The absolute atmospheric pressure at sea level is 101.325kPa (14.7? PSI).
②, gauge pressure sensor:
This pressure sensor can measure the pressure at a specific location relative to atmospheric pressure. An example of this is the tire pressure gauge. When the tire pressure gauge reads 0PSI, it means that the pressure inside the tire is equal to atmospheric pressure, which is 14.7PSI.
③, vacuum pressure sensor:
This type of pressure sensor is used to measure pressure of less than one atmosphere. Some vacuum pressure sensors in the industry read relative to one atmosphere (read negative), and some are based on their absolute pressure.
(4) Differential pressure meter:
This instrument is used to measure the pressure difference between two pressures, such as the difference between the two ends of an oil filter. The differential pressure meter is also used to measure the flow rate or the level of liquid in a pressure vessel.
⑤, sealing pressure sensor:
This instrument is similar to a surface pressure sensor, but it is specially calibrated to measure the pressure relative to sea level.
If according to the different structure and principle, can be divided into: strain type, piezoresistive type, capacitance type, piezoelectric type, vibration frequency type pressure sensor. In addition, there are photoelectric, optical fiber, ultrasonic pressure sensors.
