ENOTRAC engineers have designed most of the large electrification schemes of the Swiss traction power network, from the Zürich S-Bahn, through the Vereina and NBS Mattstetten-Rothrist lines, to the Lötschberg and Gotthard base tunnel lines. ENOTRAC has also conducted numerous technical studies and investigations for various types of railway systems in Europe, Asia Pacific, Middle East and South America. Our engineers use powerful state-of-the-art simulation and calculation software to design traction power supply systems. These programs simulate the operation of complex DC and AC power supply networks to determine the loads on traction distribution conductors (whether 3rd rail or overhead), substations, transmission lines, and cables. It is also possible to calculate the thermal behaviour of individual conductors. Such modelling provides the foundation for sound investment decisions, resulting in optimum schemes that meet the technical requirements at minimum cost.