The article describes a technique for assessing a centralized pneumatic system with consumers with various levels of requirements to compressed air regarding pressure and class of cleaning, and presents the results of this assessment. The object of study is the working pneumatic system for the technical needs of the consumers of the platform of the Nevskoye depot of St Petersburg Metro SUE. The experimental characteristics of the object have been inspected under different modes of operation; the shortcomings of the existing pneumatic system are described. A schematic diagram of a potential power-effective pneumatic system is designed through multiple parameter analysis, and taken as a basis for the modernization project currently under development. The designed scheme provides requirements for the technological process and the increase in the reliability of the pneumatic system. The results of the study can be used for modernization, operation, repair and service of pneumatic depot systems.