A Calibration Method for Thermocouple-Temperature Calibrator Based on Cold Junction Compensation

In this paper, a new calibration method based on cold junction compensation is proposed for the problem that the error of thermocouple-temperature calibrator changes with the value of cold junction compensation effected by environmental temperature. By measuring errors of cold junction compensation at different working temperatures and calculating the corresponding input and output errors of calibrator with theoretical formulae, the method overcomes the limitations of error obtained in laboratory ambient temperature, avoiding multiple measurements of different types of thermocouples. It possesses significance for on-site measurement of high-precision temperature calibrator. Experimental results demonstrate that the method is practical and accurate.