CLEARSY secures the signalling of two maintenance and handover sites in the Paris region.

26 January 2022

CLEARSY secures the signalling of two maintenance and handover sites (SMR) in the Paris region for Mobility and prepares the SIL4 certification files.

Due to their multiple functions, the maintenance and handover sites are the place of numerous flows that draw a complex traffic pattern made of pre-established routes. The SMR T2 site in Massy-Palaiseau and the SMR T13 site in St-Cyr l’Ecole, dedicated to the future T12 and T13 tramway lines that IDF Mobility (formerly STIF) is deploying in the Paris region, are no exception to the rule. Managing movements within the sites, avoiding the risk of collision between trains: this is the challenge of the signaling security software system developed by CLEARSY at the request of its partner Mobility.

The principle, explains Michael Marmolle, responsible for the project at CLEARSY, is as follows: traffic conditions are established for each route – they are provided by Mobility and implemented in the system by us. Our software checks that for each traffic request it receives, the conditions – switch position, route compatibility and absence of trains – are met. If necessary, it will lift the ban, which is set by default in the system. Although the software is not designed to provide an alternative route, it remains mobilized until the authorization is issued. The difficulty of the exercise is directly linked to the number of routes imposed by the activity assigned to each site. The SMR T12 is designed to accommodate 23 trains of more than 40 meters in length and has 80 trains.

For this project, CLEARSY reproduced the architecture successfully deployed on previous signaling security projects resulting from its collaboration with Mobility (lines 2 and 3 of the Nice tramway, Caen tramway, Luxembourg tramway). The software, one for each site, is embedded in safety PLCs installed on the platform in signaling cabinets. And the RS4 safety relays that interface the equipment to the track come from its laboratories. CLEARSY prepares the safety files (SIL4 according to the 50128 standard) for Certifer. The SMR 13 software and its SIL4 certificate is delivered since July 2020 and the SMR 12 software and its SIL4 certificate is delivered since July 2021. The tests on the T12 depot site are in progress, those on the T13 site are completed.