This study was focused on the temperature measurements and their uncertainty calculations of the iButton DS1922L Thermochron sensors. Besides this, the measurements of the response time of these thermometers were also taken therefore the time constant was calculated. There were fifteen thermometers used for the calibration measurements and three thermometers used for the measurements of the response time of the sensors. The measurements were performed in the calibration laboratory of the Slovenian Environment Agency, which is accredited for calibration of thermometers, barometers, hygrometers and air quality analyzers. The measurements of temperature deviation of the sensors took place in a climatic chamber, where the temperature, measured using iButton thermometers, was compared to the temperature, measured by the reference thermometer. The measurements were performed from the temperature -40 °C, to the temperature 40 °C, with the step of 10 °C. In most cases, the bias of these sensors was between 0.2 °C and 0.5 °C.
The measurements of the response time of these thermometers took place in both, the climate chamber, where the temperature was set to approximately 10 °C and the relative humidity generator, where the temperature was set to approximately 25 °C. In both devices, the temperature, measured by iButton sensors, was compared to the reference thermometer. Four measurements were performed, using three different sensors, so there were effectively twelve measurements, from which the time constant was calculated. The mean value of measured response time was 234 seconds.
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