A pressure transducer is used to convert a certain value of pressure into its corresponding mechanical or electrical output. Measurement if pressure is of considerable importance in process industries. Types The types of pressure sensors are differentiated according to the amount of differential pressure they are able to measure. For low differential pressure measurement Liquid Column Manometers are used. Elastic type pressure… Read More »
About Vacuum Gauges For pressure measurement below atmosphere or vacuum gauge, different gauges are available. Manometers and bell gauges can go up to 0.1 Torr. Diaphragm gauges are usable up to a pressure of 10-3 Torr. For pressure below this value, electrical gauges like Pirani or Ionization Gauges are used. Vacuum measurement is broadly classified into Mechanical Type, Thermal Type, Ionization Type, and Radiation… Read More »
Absolute Pressure– This is a combination of gauge pressure of the media with the pressure of the atmosphere. When the location changes, say as per the change of altitude, the atmospheric pressure also changes which compel the reference point to differ as well. If an absolute pressure sensor is used for eliminating the reference of varying atmospheric pressure.
A basic pirani gauge consists of a fine wire of tungsten or platinum of about 0.002 cm in diameter. This wire is mounted in a tube and then connected to the system whose vacuum is to be measured. The temperature range is around (7-400) degree Celsius and the heating current is between (10-100) mA. A bridge circuit is… Read More »