Power System Suite is a universal programmed product, allowing to check in complex the possibility of application of technical decisions connected with the circuit formation at the stages of variants' comparison during the process of design and within the changing conditions of exploitation of industrial enterprises' electric supply systems by means of calculation methods. The program is intended for investigation of the enterprise's electric supply system and as a result, for increase of its operating reliability and also for running on a schedule of the electrical equipment's scheduled-preventive works (SPW). The present program allows to estimate and optimize parameters of the electric supply system, imitate regular and emergency situations and can be used as a simulator for operative personnel of power subdivisions of an enterprise. PSS contains the base of models of the electric supply circuits' power elements.