Jumpers for extremely cold conditions

Shaky situation

Jumper cables carry power/data between train coaches to assure safe and efficient operations. Designed for Nordic countries, this new silicone-sheathed cable meets the challenge of -50ºC temperatures and perpetual movement in an exposed environment.

Silicone solution

Flexible silicone is the best sheath for harsh conditions. However, high temperatures used during extrusion risk melting the polyethylene-insulated cable core. The new technique avoids this by threading the cable core into a stretched silicone sheathing tube without extrusion.

Applying experience

During a visit to Nexans Shanghai, we observed a similar process which led us to imagine how it could be applied to jumper cables for rolling stock operating in very cold conditions. The process was simple and easy to apply. Next, we designed modular equipment which allowed us to manufacture short cables adapted to customer needs (generally one to three-meters long). Then, we subcontracted the silicone tubes, and found a solution to print identification markings on the tube without deformation during manufacturing. Results were very positive, and an initial order was recently shipped for the Kazakhstani market.


This innovation allowed us to meet a growing market demand in colder countries and to complete our offer for the international rolling stock industry, which already includes custom-designed jumpers containing Ethernet Category 5 data cables. It reinforces our status among OEMs, who see Nexans as a technical problem solver. Via Nexans’ Confecta resources, we now have a fully-connectorized jumper cable solution which our sales teams can present as “plug and play.” The next step is to check the elastic deformation of other materials used in rolling stock so as to organize a “jumper on demand” service.