Cable architecture rethought for new Paris train fleet
Nexans is supplying around 25,000km of specialised rolling-stock cable for 172 new trains that will operate in Greater Paris.
Bombardier is currently building the state-of the-art Francilien suburban trainsets for the French train operator SNCF.
The Francilien, previously known as the Nouvelle Automotrice Transilien (NAT), is a single-deck design based on short, wide car bodies with a single door on each side, which can move as many people as double-deck trains of equal length.
Of the 172 Francilien trainsets now in production, 77 eight-car trains are for routes serving Paris Nord, 55 seven-car trains for Saint-Lazare, and 40 eight car trains for Paris Est. The first trains entered service in the Paris region in December 2009.
In designing the Francilien concept, Bombardier had to meet SNCF's stringent requirements in terms of safety, reliability, maintainability and life cycle costs. This called for the redesign of critical elements like doors (so that ease of access could be assured and breakdowns avoided), back-up controls to allow trains to be easily reconfigured in the event of component failure, and secure data transmission between trains and control centres for efficient train management. A major development that places further demands on the cabling systems is the comprehensive IP-based communications package, with four LED screens in each car displaying travel and entertainment information and dynamic route maps. In addition, passengers can watch digital TV with sound transmitted by special earpieces.
The project has drawn on Nexans' full range of Flamex cable solutions, including power cables for the electric motors; high-voltage connections between the pantograph and the transformer; low-voltage power supply for cars; control cables, harnesses, jumpers, and data cables throughout the trainset to support everything from train control to surveillance, video and Internet.
Each car has a roof-mounted air-conditioning unit, and for the first time heating is incorporated in the floor, which keeps the corridor dry and frees space under the seats. This open train interior called for a complete rethink and redesign of the cable architecture. For example, cabinets are now located at each end of the train instead of between cars. Cables are often pre-installed on a large frame for easy attachment to the roof of the car, with pre-connections ready to be plugged into various components.
As part of the rethink of the cable architecture, Nexans applied a value engineering approach to ensure that optimum use was made of the available cable cross-section - so that the same level of service could be provided with less cable. Attention was also paid to standardisation of the main cable runners for easier and more efficient installation.
The cables will be manufactured at three plants in France and in Germany and will be delivered until 2015.
[Image: C Recoura - TRANSILIEN-SNCF]