4. Ground contact line

4.1 Lateral conductor and wiper

The ground contact line consists of a rigid conductor attached to the sleepers by means of insulating supports, outside the track. A friction pad attached to the vehicle picks up the current, which is returned, except in exceptional cases, via the running rails (figure 22 ).

Such a configuration, using the track, fits into the track's normal gauge, enabling a much lower investment cost than an overhead system. What's more, as the conductor rests on the ground, it can have a large cross-sectional area, enabling high currents and reduced Joule-effect losses....