The new Munich S-Bahn trains are set to be the most modern in Germany – more digital, more connected, and more future-proof than any of their predecessors.
With this goal in mind, Siemens Mobility is currently developing and building the 90 vehicles and has therefore decided to integrate high-performance embedded hardware that is both powerful and energy efficient.
The high-performance BL74W box PC from duagon was chosen for the embedded hardware of the two central train servers installed in each vehicle. According to Gunther Gräbner, who is overseeing the project as a solution architect at duagon, there are several reasons for this. His task is to combine the various duagon standard products to meet customer requirements and adapt them precisely as needed. An important requirement for Munich’s S-Bahn is that the hardware components have sufficient resources to be able to run future applications in ten or fifteen years’ time without any problems. “Our product portfolio is scalable. To meet this requirement, it makes sense to switch from DIN rail systems, which are commonly used as train servers, to a more powerful box PC,” explains Gunther Gräbner.
Efficient in three ways
A second aspect played an important role in the specific choice of the BL74W: efficiency. “We use energy-saving components, which is why we can work with a fanless design. We also do without components that need to be replaced regularly, such as batteries or rechargeable batteries. The BL74W is therefore maintenance-free and specially designed for use in the harsh railway environment, which keeps the maintenance costs of the new S-Bahn trains low.”
In addition, Siemens Mobility is installing another piece of embedded hardware from duagon in the new S-Bahn trains: The many different passenger comfort systems and 5G routing run on CompactPCI Serial systems from duagon. “The CompactPCI Serial system and the box PC both use the same processor board. The resulting synergies for software development keep development processes and costs lean at Siemens Mobility and train operators and are an important efficiency factor.”
Box PC for high performance
The BL74W standard product is equipped with 13th generation Intel Core processors. These are the first to use Intel’s new hybrid architecture with up to 14 performance and efficiency cores (6P+8E) for scalable performance from 15 to 45 W TDP. To cope with the harsh operating conditions in the railway environment, the DDR5 RAM is soldered in place and offers up to 96 GB of storage capacity. Depending on the type of application, the BL74W can combine up to four integrated 5G modems. The version for the Munich S-Bahn from Siemens Mobility has one modem installed.
Use as a central train server
In the new S-Bahn trains, the BL74W functions as a central train server – two per vehicle. Among other things, it provides all other train systems with the necessary software packages and distributes updates that it receives over the air.
The first vehicles are scheduled to enter passenger service in Munich at the end of 2028. In order to meet the ambitious schedule for planning, development, and production, duagon will deliver the first prototypes of the hardware this year. This will allow engineers from Siemens Mobility and train operators to configure, coordinate, and test the systems.
Further information on this topic can also be found in the Siemens Mobility press area.