Pressure calibration is the comparison of the output of a device used to measure pressure with that of another pressure measurement device, or pressure measurement standard. This usually involves plumbing the unit under test (UUT) to the standard device and generating a common pressure in the measurement circuit. The outputs of the devices are compared at one or more pressures, typically from the lowest to highest readings of the UUT’s full scale range, or the range for which it is normally used. This comparison process is performed in a chain from the highest level of fundamental pressure realization, down to every day pressure measurement devices, to ensure pressure measurements are accurate and comply with accepted or mandated standards.
DIGITAL PRESSURE GAUGES
Digital pressure gauges measure the pressure within a system in a special manner. They convert the pressure to an electronic signal. The gauge displays the pressure using a digital display, furthermore the signal can be used to control equipment. Digital gauges in comparison with analog ones have a higher accuracy.
Pressure measurement is the analysis of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressure and vacuum. Instruments used to measure and display pressure in an integral unit are called pressure meters or pressure gauges or vacuum gauges. A manometer is a good example, as it uses the surface area and weight of a column of liquid to both measure and indicate pressure.
DIFFERENCE PRESSURE GAUGES
Differential pressure gauges measure the difference between two pressures. They are suitable for the monitoring of filter contamination, for level measurement in closed vessels, for overpressure measurement in clean rooms, for flow measurement of gaseous and liquid media and for the control of pumping plants.
A pressure transducer, often called a pressure transmitter, is a transducer that converts pressure into an analog electrical signal. Although there are various types of pressure transducers, one of the most common is the strain-gage base transducer.
A pressure switch is a form of switch that operates an electrical contact when a certain set fluid pressure has been reached on its input. The switch may be designed to make contact either on pressure rise or on pressure fall. Pressure switches are widely used in industry to automatically supervise and control systems that use pressurized fluids.