In this paper authors present the result of a study oriented to assess the metrological characteristics of measuring systems used for verifying the variation of the ratio errors and phase displacements of inductive voltage transformers vs. temperature. Experimental results show that the designed equipment as well as the set up realized can be considered as a benchmark for the verification of the variations of ratio errors and phase displacements of up to 0.1-accuracy class voltage transformers vs. temperature. In addition, the sources that more contribute to the uncertainties on the ratio and phase errors have been investigated and discussed in the paper along with suggestions on where to act to further improve the accuracy of the presented set up.