Csm Pilatus Zahnradbahn Eselwand Tunnel Ss 6ecbc57fc4

Westermo provides networking for world’s steepest cogwheel railway

Feb. 6, 2023
Westermo to help with railway’s train-to-ground network, including a redundant, Ethernet ring architecture installed directly on the mountain

Westermo reported Jan. 23 that it’s been chosen to supply wireless and wired networking technology for larger, faster rail vehicles for the 130-year-old Pilatus-Bahnen railway, which is still reported to be the world’s steepest cogwheel railway.  

The train climbs the path from Alpnachstad to Pilatus Kulm, with passengers able to view flowering alpine meadows, striking rock formations and snowfields. The railway has become one of Switzerland's most successful tourist attractions. Because of its popularity and large number of passengers, it was decided the railway needed more modern trains. Likewise, controls used in the original trains were based on mechanical and electromechanical elements. For the new trains, a modern, electronic train control system from Actemium Schweiz AG LeitTec was installed.

However, to establish connections between trackside control units and moving trains, reliable wireless communications were required. Pilatus uses PbS (position-based signaling) from Actemium, and enlisted Westermo to help with the railway’s train-to-ground network, which included a redundant, Ethernet ring architecture that was installed directly on the mountain.

"A project like this one has never been built before and is essentially a prototype. To be able to accomplish this project, we needed partners like Westermo, who actively contribute their know-how and support us with planning,” says Patrick Blaser, operations manager and executive board at Pilatus. “Ongoing project changes were always supported and professionally implemented by Westermo."

The participants add the new network also had to balance two critical requirements—infrastructure costs and cybersecurity. The ICT minimum standard, the Swiss government's cybersecurity recommendations for critical infrastructures, also had to be considered. Pilatus, Actemium and Westermo planned an encrypted data network with several security zones, monitoring and surveillance systems.

Going train-to-ground

In addition, Westermo's ring protocol for high-availability Ethernet networks, FRNT (fast recovery network topology), provided network redundancy. Its ring architecture ensures data transfer via other paths in the unlikely event of a device or network link failure. To make sure the network can be operated securely and is protected from the outside, security functions such as data encryption, port security, active firewalls and other mechanisms for a secure data network were taken into account in the concept and later implemented. 

Westermo’s Ibex-RT-370 infrastructure access points were installed trackside to provide WLAN connection to the vehicles, along with redundant routing switches with firewall functionality in the stations. The network onboard the trains is based on Westermo’s Viper-212A managed routing switches and Ibex-RT-320 wireless clients that communicate via Wi-Fi with the trackside access points. This train-to-ground communication network setup ensures reliable communication between the trains and the control system.

Also, a collision warning system between the trains was implemented using Westermo’s wireless technology. A wireless local area network (WLAN) connection is automatically established between two vehicles when they approach each other. This connection allows the steering systems to exchange data, enabling them to travel virtually in tandem and avoid collisions.

With its highest point over 2,000 meters above sea level, Mount Pilatus often has more than 10 meters of snow on its summit in winter and is often exposed to extreme conditions. To protect the railway’s infrastructure from snow and meltwater, it’s partially dismantled in autumn and reassembled in spring. In order to simplify and streamline this process, a trackside radio equipment (TRE) box was developed and implemented by Westermo, containing WLAN access points, antennas and power splitters. These TRE boxes were delivered to Pilatus-Bahnen fully wired, tested and configured, allowing for cost and time savings during the installation and commissioning. Thanks to a sophisticated assembly and disassembly system, the boxes can be easily dismantled in the autumn and reassembled in the spring. This also ensures that the antennas mounted on the TRE box are correctly aligned again after reassembly.

About the Author

Jim Montague | Executive Editor

Jim Montague is executive editor of Control.