Track circuits and automatic cab signaling are not stable at the electrified railway sections due to interference effect caused by traction current. The process of noise generation depends on a variety of factors that is why it is quite difficult to identify the reasons for generation of unacceptable noise level. The process of noise measurement under service conditions for the assessment of electromagnetic environment in the electric traction network and electric locomotives is complicated and demands considerable amount of time and resources on its fulfillment. Electromagnetic environment may change rapidly, while the results of such measurement are hard to extrapolate to other conditions of traffic intensity or-and different weight and speed of trains at this section, as well as other railway sections. The above-mentioned proves that the theoretical research and the elaboration of noise level calculation methods for railway automation and remote control facilities in question under different service conditions are topical in the given field of study. Interference from traction current in these facilities appears when asymmetry of longitudinal and-or lateral resistance of track ways takes place. Some results of elaboration of calculation methods were stated in the article identifying the behavior of change in the level of noise from traction current along non-homogenous track lines equipped with track circuits. Electrically long track ways are presented as a cascade of three-terminal devices. The length of these segments is selected on condition that the required accuracy of calculations is provided.