Electronic module "boîte à pont"

The requirement

The job of a signalling tester involves checking that systems are working properly by closing dry contacts for set periods of time. However, there is a risk of forgetting to manually remove these temporary bridges, which can compromise safety. To overcome this problem, it is necessary to design a programmable electronic module, called a ‘bridge box’, which can create a temporary bridge with a limited duration. This tool aims to reduce the risks associated with oversights due to interruptions or faults during testing, thereby guaranteeing the integrity of safety installations. TSO Signalisation is a company specialising in railway signalling systems, offering innovative solutions to ensure the safety and efficiency of transport networks through its expertise in the design and integration of safe railway signalling systems.

The solution

This module, once programmed by the user, automatically switches off the bridge at the end of the timer, thereby restoring the safety condition. The user configures the timer by turning the switch to the INIT position, enters a password and sets the duration using the buttons, then saves using a key. To commission the system, the user connects the test leads, turns the switch to the ES position and activates the bridge using the key. The bridge deactivates automatically after the time delay, indicated by LEDs and a buzzer. To stop, turn the switch back to the HS position and disconnect the leads. The system is powered by a rechargeable battery via USB-C, providing 5 to 10 hours of autonomy.

Experimentation

On 20 March, during tests in Cerbère, a tester used the TSO Signalisation electronic module "boîte à pont" avoid forgetting the axles at the end of the session. The first test revealed safety problems and an unpleasant setting, but the designer corrected these points on the spot. After 6 consecutive iterations of the 4-month sprint, the box worked as expected. A few improvements are still needed, but this prototype promises to reduce the risk of test bridges being forgotten.

Learning

The experiment led to rapid progress thanks to immediate modifications in the field. Feedback from SNCF Réseau has helped to improve the operation and size of the box. Technical and financial optimisations are underway, with needs identified for a reduction in size, improved autonomy and simpler time delay settings.