Improved method for pressure measurement in saturation chamber of primary dew/frost point generators

摘要

This paper describes two methods for measurement of air pressure inside the saturation chambers of two primary dew/frost point generators, used as national humidity standards at Laboratory for process measurement (HMI/FSB-LPM) in Croatia. Together, the generators cover the dew/frost point temperature range from -70 degrees C to + 65 degrees C. Low range generator operates at air temperatures between -70 degrees C and 5 degrees C, while high range covers the range between 1 degrees C and 65 degrees C. The saturation pressures considered are in the range between atmospheric and 1060 hPa, at the air flow rates between 1.0 L min(-1) and 2.5 L min(-1).