**1. Introduction**

The experimental study of the energy action/behavior of an industrial user allows to highlight its energetic performance, practical ways to improve its energy use, as well as validating the theoretical hypotheses formulated in order to assess this user. Assessing the power quality supplied in the public system and observing the quality indicators for compliance with accepted standard limits plays an important role in order to establish the optimal functioning parameters for this industrial power user. In this paper, the results of the experimental study achieved at a largescale/industrial power user are exposed, along with the problems that emerged from this research. Moreover, solutions for solving these kind of problems are indicated. The analysis of the power supply quality of the three-phase general power supply circuit of the analyzed user was performed on the 110 kV side in the measuring cells in the secondary measuring circuits of the T1 110/20 kV transformer, 16 MVA.
