CHARACTERIZATION OF A TEMPERATURE CONTROLLED ENCLOSURE AND UNCERTAINTY ANALYSIS

Abstract

Temperature-controlled enclosures such as drying ovens, incubators, and sterilizers are widely used in laboratories and industrial settings. In such systems, it is essential that the temperature distribution within the working volume be as uniform as possible to ensure consistent exposure of samples to thermal conditions. This study presents a detailed methodology for the characterization of temperature-controlled volumes, based on metrological principles and international guidelines. A practical application on a drying oven is included, where temperature measurements were carried out using 15 calibrated type K thermocouples connected to a multi-channel data logger. The placement of sensors, the measurement procedure, and the evaluation of results including temporal fluctuation and spatial distribution are explained. Additionally, the uncertainty components affecting the measurement results were identified, and a complete uncertainty budget was calculated. The results show a systematic deviation from the setpoint, which is discussed in terms of the chamber's internal control behavior. This study aims to support calibration laboratories by providing a reference for both characterization practices and uncertainty evaluation.

Keywords

• Temperature-controlled volume
• Drying ovens
• Temperature
• Thermocouple
• Temperature calibration

References

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