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Successful Testing of the DAC with Powerline Train Backbone

Mar 28, 2025 | Latest News

As part of the FP5-TRANS4M-R project a prototype test train has successfully tested the most relevant automated functions using the Digital Automatic Coupling (DAC). The tests, conducted with a prototype train, demonstrated to quickly adapt the new Powerline PLUS communication technology as the )[1]. With this promising results, essential development are now needed to achieve a production-ready solution for the digital automatic coupling.

The FP5-TRANS4M-R project, co-funded by the Europe’s Rail Joint Undertaking, aims to develop and test innovative technologies for rail freight transport. The project includes large-scale demonstrators in different European regions while installing a train test lab to allow for an agile approach testing various prototypes and ensuring the overall system integration. One of the demonstration trains is running in Switzerland and it has made substantial strides in testing , which include automated brake tests, train composition detection, train integrity monitoring, and automatic uncoupling. These functionalities were tested under real operating conditions using a specially equipped prototype train.

Project Execution and Test Environment

The FP5-TRANS4M-R demo train being tested in Switzerland was based on the mechanical and pneumatic center buffer coupler (DAC2) currently used in Switzerland. Thistest train was equipped with the Powerline PLUS technology, which forms the train backbone communication system. This system enables transmission of Ethernet/IP data packets between the locomotive and all wagons in the train via the 400 VAC train power cable.

The test train consisted of four test wagons, two intermediate/adapter wagons, and an equipment and measurement wagon that emulated the locomotive’s functionalities. Standard SBB Cargo locomotives were used for mainline runs and shunting operations but were not integrated into the test system.

From February to December 2023, conducted extensive tests, including static and coupling tests, shunting tests, and test runs covering a total distance of 4,211 kilometers. The test environment was set up in Lupfig, Aargau, Switzerland, with additional tests carried out in various locations, as in Dottikon, Wildegg, and Basel Marshalling Yard.

Key Findings and Achievements

The tests focused on four primary automated train functions train composition detection, automatic brake test, train integrity monitoring, and automatic uncoupling. The results were highly encouraging, demonstrating the prototype realisation of these functions based on the PTB communication system.

  • Train Composition Detection: The PTB Train Topology Detection protocol successfully determined the sequence and orientation of all wagons in the train.
  • Automatic Brake Test (ABT): The system, integrated with the PTB communication system, performed flawlessly. The data was transmitted via PTB, and the brake tests were successfully conducted using the existing PJM WaggonTracker system.
  • Train Integrity Monitoring: The train integrity monitoring system, based on the detection of communication losses in the PTB system, proved to be very effective. The tests showed no false alarms, and the system met the expected response time requirements.
  • Automatic Uncoupling: The prototype system for automatic uncoupling, developed by Voith, worked well during the tests. Both manual uncoupling using a pushbutton on the wagon and remote uncoupling via a tablet were successfully tested.

Finalisation of the Powerline Train Backbone within EU-Rail R&I programme

Capitalising on the successful test results, the project team confirmed the next R&I steps required to achieve a production-ready solution.

  • System development: The full DAC systems and the FDFT functions need a state-of-the-art system development focusing on functional safety aiming for the prove of safety to achieve the needed integration ability.
  • Power Supply System: The on-board power supply for the wagons can now be further optimised including with a more robust power supply system.
  • Insulation Resistance: address the stabilisation of insulation resistance in different environmental conditions.

Conclusion

The successful tests of the DAC+ PTB mark a significant achievement in the FP5-TRANS4M-R project. The demonstrated automated train functions based on the PTB communication system are promising for the future of digital freight trains. The journey towards a production-ready solution the project team is fully engaged and energized to finalized the last R&I steps and work towards achieving a standardised, interoperable set of solutions for the Full Digital Freight Train Operations (FDFTO).

The ongoing development and testing in the FP5-TRANS4M-R project that will contribute to CENELEC standardis through the EU-Rail System Pillar process , will ensure that the DAC technology is ready for widespread adoption in the rail freight industry.

As the project progresses, the goal remains to create a financial suitable and effective driven, reliable, efficient, and fully automated digital freight train system that could revolutionise rail freight transport across Europe.

[1] PTB (Powerline Plus Train Backbone) is one of the communication technologies for the data backbone of the future freight train

[3] https://rail-research.europa.eu/european-dac-delivery-programme/

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