The evaluation of the long-term drift of low-resistance measures using time series

The effect of long-term drift of a precision measure on the calibration of other measuring instruments or measures is necessary for careful monitoring of their real metrological characteristics. If such drift is not taken into account, or taken into account, it can lead to incorrect calibration of other measuring instruments or measures. The results of the evaluation of the long-term drift of five low-resistance precision measures with nominal values of 0.0001 Ω, 0.001 Ω, 0.01 Ω, 0.1 Ω, s 1.0 using polynomial regression of the 3rd order are given. The specified approximations of the drift lines of the resistance measures have a value of the coefficient of determination from 0.44 to 0.84, that is, they confirm their adequacy. The measures have historical calibration data from 2002 to 2023. Sufficient adequacy was achieved in the description of the drift lines for all low-resistance measures. Uncertainties of measurement in the calibration of measures are estimated with values from 0.3 ppm to 6.9 ppm.