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Assembling a calibration facility for dynamic characterization of humidity sensors


The dynamic response of sensors plays an important role in several measurements for industrial and research purposes. Especially capacitive humidity sensors, the most widely used types of sensors, show significant hysteresis and long response times. Yet, there hasn’t been any metrologically validated standard for analyzing their time response behavior. Therefore, a calibration facility has been developed within the framework of the EMRP project “Meteomet 2”, which is suitable to provide a highly accurate reference signal with optimum time resolution, based on an optical measurement technique. The first test measurements at 140 Hz already enabled detailed analysis of a commercial polymer sensor with response time (10/90) of 0.3 Hz.