How EULYNX enables legacy relay interlocking upgrade to ERTMS compatibility?
The European Rail Traffic Management System (ERTMS) is a single European signalling and speed control system that ensures interoperability of the national railway systems. Connection between ERTMS and EULYNX is the foundational signalling command and control communication logic which is executed in the system. Command is given by train or dispatcher and it goes down to each track side objects. Locomotive gets needed information through Radio Block Center (RBC). EULYNX´s purpose is to harmonize communication protocols used in the message exchange between different elements of the system. (Equipment - Interlocking - Radio Block Center - Traffic Management System).
Relesoft Relynx family is a EULYNX protocol driven software designed for two purposes: 1) Enable interlocking interoperability with digital remote control systems and 2) serve as an object controller for track side equipment to enable connectivity to interlockings. EULYNX is like the common language to ensure different suppliers' systems work together. Sometimes it is a value to have independent software ensuring modular structure. Here you can read how FTIA implemented gateway to their relay interlocking systems.
When considering ERTMS, modernisation typically people have misunderstanding that it means automatically interlocking upgrading and it is a surprise when the possibility to continue with existing interlocking is a reasonable option. Specifically asset managers are excited about the possibility to extend the life cycle for existing infrastructure without any limitations to go forward with the ERTMS upgrade program.
Relay based interlockings are still a proper and working solution in many cases from asset management perspective. When the ERTMS communication is enabled it becomes also relevant from network and traffic management perspective. So We could say that software like RELYNX is opening the door for optimization from capital investment (CapEx) and operational cost (OpEx) perspective. From the technical point of view it is essential to understand that when demanding EULYNX interoperability different systems from different providers can work together under a third party remote control system. When there is stamina and courage to take steps toward described settings, there starts to be visible reduction to costs.
To answer the title of this post. Short description about interoperability and connection to ERTMS on a technical level is as follows. When relay based interlocking is communicating towards signals, point positions, etc. the communication can be translated to “EULYNX language” with gateway software. These messages are then sent in a shared protocol format based on the control system or Radio Block Center (RBC). From RBC the needed information is then communicated to locomotives (OBU,DMI) according to ETCS principles.
Are there any risks or problems identified? From the technical perspective there are minimal risks. One computer is added to relay house, testing is needed but it can be executed without disturbing the traffic. The biggest issue is the natural reaction to new unfamiliar topics. It is easy to contract ERTMS as a turnkey and outsource risk to contractors. This is why I am encouraging everyone to pilot and test EULYNX based solutions with relay interlockings to learn and grow in confidence. This is safe and easy to do for example on secondary network locations. This is the only way to learn and take steps towards more open digital railway infrastructure.