THE MEASUREMENT UNCERTAINTY OF A PRESSURE BALANCE FOR LOW GAUGE DIFFERENTIAL PRESSURE MEASUREMENT

摘要

This paper presents a simplified model for the evaluation of the measurement uncertainty of a pressure balance (Type V1600/4D, manufactured by Pressurements, Ltd.) used in our pressure calibration laboratory as a standard pressure balance for gauge and differential pressure measurement. The gauge measuring range of this gas-operated balance runs from a nominal pressure of 20 Pa to 16 kPa and its minimum differential pressure measurement is 5 Pa. The results for measurement uncertainty obtained from the model are based on calibration data provided by the accredited calibration laboratory. In the measuring range up to 600 Pa, its measurement uncertainty is less than +-0.16 Pa, and in the range up to 16 kPa it is less than +-0.02 %; this shows good agreement with the manufacturer's data. The contributions of certain parameters to the total uncertainty of pressure measurement are also presented.