Trafikverket and Pilz modernise rail communications with fibre optics

The Swedish Transport Administration Trafikverket and Pilz have jointly reached an important milestone in the modernisation of the nationwide rail network.

The jointly developed ‘Safe Relay Messages over Opto’ (SRO) solution has, following a successful field trial phase, received generic approval. This means that the communications infrastructure along the Swedish rail network can in future be gradually converted from copper to fibre-optic technology.

With the SRO project, Trafikverket is modernising data communication along its railway lines and laying the foundations for future-proof transmission of safety-critical signalling data. The basis for this is Pilz’s safe and modular railway control system, PSSrail, which reliably transmits information between signal boxes and trackside infrastructure.

Modernisation without replacing the signalling technology

A particular challenge of the project was to introduce modern communication technologies without having to fundamentally alter existing control and safety systems. Together with the engineering consultancy Sweco, Trafikverket and Pilz developed a solution that enables precisely this. The existing relay technology along the line is retained, whilst data transmission is switched to modern fibre-optic technology.

This allows modernisation measures to be implemented with minimal disruption to the existing infrastructure and ongoing rail operations. At the same time, the solution meets the highest safety requirements in accordance with SIL 4 and contributes to greater availability of the communications infrastructure.

The foundation for the digitalisation of the rail network

With the generic approval Trafikverket is laying the groundwork for a cost-effective roll-out of the technology to further sections of the line. The significantly reduced approval process simplifies future modernisation projects and lowers their costs. At the same time, the new infrastructure paves the way for further digitalisation measures in the Swedish rail sector.

Shaping the digital railway together

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