Calculating Calibration Uncertainties in an Automated Temperature Calibration System

Document(s): 

Calculating Calibration Uncertainties in an Automated Temperature Calibration System (426.88 KB)

Some of the basic calibration uncertainties to consider with an automated temperature calibration system like the Hart 7380 bundles are the calibration uncertainties of the reference PRT, the drift of the PRT, uncertainties arising from bath uniformity and stability, and the uncertainties associated with the readout used to measure the unit under test and the reference PRT. This application note describes the evaluation of those uncertainties. Additional uncertainties that depend on the performance of the specific unit under test or the entire class of instruments for which the procedure applies may also be evaluated and included on a case-by-case basis. These include hysteresis, short-term stability, immersion effects, and self-heating.