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In this article, the object of the study is the power supply cables for non-traction railway consumers. The electrical parameters of the insulated conductor are determined. Primary parameters of the aluminum shell of the main power supply cable are obtained. As a result of solving the problem, the transient resistance of an isolated conductor is determined. From the boundary conditions, the propagation constant of the metal shell of the power supply cable in the polymer insulating coating is determined. As a result, the values of the transition resistance obtained by different methods are the same.

The article analyzes the change in the strength properties of structural materials used in the production of current collectors of electric rolling stock, proposes a method for calculating the reduction of resource indicators of elements of a system of moving frames of electric current collectors made of hardened aluminum alloys as a result of the thermal effect of the flowing current. The features of heating the levers of the current collector during laboratory tests are considered. The most heat-stressed units and elements bearing a mechanical load are installed. The dependence of the thermal degradation of the levers of a system of moving frames at various temperatures is determined. The nonlinear conversion function is calculated for calculating the integral value of thermal wear. A method is proposed to increase the reliability and performance of current collectors, based on the use of permanent temperature control of its key elements.

The article shows that the replacement of concrete poles should be based on their actual corrosion state. Authors propose a new method for determining the corrosion state of the contact system concrete poles underground part, which allows to carry out measurements on the two poles at the same time. In this case, second pole acts as a current electrode. There is a formulas for determining the resistance of concrete, resistance and capacity of «steel - concrete» interface region. This algebraical expressions are results of the transient process analysis for the contact system poles equivalent circuit. The values of these parameters define the corrosion state pole in the underground part. Using of the proposed method will significantly reduce the time and labor costs of diagnostic procedures.

The article is about defining corrosion state of overhead structures underground part. Specially designed concrete models are used for experiments and calculations. These models are made with the fabric technology of overhead structures creation. «Steel - Concrete» interface region parameters are calculated with a help of transient process which situated when DC power supply is connected to the scheme. There is a formulas and a methodic for calculation needed parameters. In the end of the article theoretical curve is located. It exactly coincides with an experimental curve.