Automated bias-removal resistance measurement circuit for precision on-site temperature calibration exploitation of state changes of materials

An innovative process is proposed for the calibration of thermometric devices, combining materials which change state at primary temperature calibration points defined in international standards, and electrical impedance measurement techniques. The process will use pure samples of such materials and a measurement apparatus which enables the automated matching of the elimination of measurement bias to each of a number of calibration points, improving resolution and accuracy. The proposed process will be low-cost to allow implementation and regular calibration of temperature sensing and controlled devices in a standard manufacturing process.