COMPUTER OPTIMIZATION OF THERMOCOUPLE CALIBRATION

The report presents two related improvements to the results of thermocouple calibration. The first is analytic: two computation schemes are recommended for drawing an unbiased calibration curve through the data. The second is experimental: the mean calibration curves for iron-constantan, chromel-alumel, and copper-constantan thermocouples have been determined experimentally. It was found that the calibration curves computed from a few data better fit this mean curve if the input data are observed at the relative maxima and minima of these mean curves. On this basis, the report recommends at which temperatures the calibrations should be performed for each of the three thermocouples. The computation methods are quite general and may be applied to any calibration where the correction or error relative to a theoretical value is the accepted format. (Author)