6 October 2017

Traction Return Current Control Performed in Morocco Using Unique Method

This summer, Eurailtest was faced with the challenge of checking traction return current circuits on 100 km of the 200 km of high-speed line between Tangiers and Kenitra on behalf of its client ANSALDO STS.


On this infrastructure, traction return current was checked by means of an innovative method more commonly employed for urban light rail, suitably adapted to high speeds by Eurailtest member laboratory LEM (Test and Measurement Laboratory), rather than the usual process using a combination of Lucie and Vulcain cars (a service also offered by Eurailtest).

Measurements were performed over 3 weeks and consisted of:

–        measuring the balance between traction return current in the two stretches of rail within a single track circuit.  Imbalance must be below 10% for the signalling system to be able to operate properly.

–        measuring traction return current as such to enable ANSALDO STS to authorise short-circuit tests on the line.

By adopting this method, it was possible to obviate the risks inherent in bringing in expensive testing equipment (Lucie-Vulcain cars) and complete tests on time and to budget in a highly complex environment, to the satisfaction of ANSALDO STS.

Input from these tests was an essential prerequisite for speed ramp-up tests to V320 km/h scheduled for this autumn and also performed by Eurailtest.