On the basis of an earlier software development the authors created a single multifunctional software complex «POTERI V1.1: SETI, REG10PVT»  (next POTERI), calculation of energy losses in electric networks 6-110 (220) kV with high precision and reliability. The paper presents the general structure of the software complex POTERI, as well as a brief description of the software modules and features of their functioning: SETI, REG10PVT, VES, RES. Testing of software modules, algorithms and testing of the complex as a whole in network enterprises of the Russian Federation is carried out.