Resistance thermometer testing

• Main Authors: DR HECTOR AUGUSTO NAVARRO, DR HONOR ROSEMARY TAYLOR
• Format: Patent
• Language: English
• Published: 05.12.1984
• Subjects: MEASURING; MEASURING QUANTITY OF HEAT; MEASURING TEMPERATURE; PHYSICS; TESTING; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR

In a method for testing the characteristics of a resistance thermometer comprising a resistance element and a support for the resistance element, the support being intended to contact a material the temperature of which is to be sensed, a formula is derived representative of the thermometer's heat transfer function, the formula being of second or higher order and including constants representative of at least the thermal resistance of the support, the thermal capacitance of the support, the thermal resistance of the boundary layer between the support and its surroundings, and the thermal capacitance of the boundary layer between the support and its surroundings. A heating current is passed through the resistance element for a limited period to heat the thermometer. Variations with time of the resistance of the element as its temperature varies are monitored, and the formula constants are calculated such that the formula fits the monitored variations in resistance, the calculated constants being a measure of the characteristics which they represent in the formula.