Signalling systems for high-speed connections

The TCDD high-speed line between Istanbul and Ankara provides future-proof and sustainable mobility for passenger transport.

Reliable operation is ensured, among other things, by a comprehensive lightning and surge protection concept from DEHN.

DEHN solution	External lightning protection of control system buildings; coordinated lightning and surge protection of the power supply and signalling and control systems
Customer	State railway company Türkiye Cumhuriyeti Devlet Demiryolları (TCDD)
Sector	Rail technology
Products	HVI Conductor, BLITZDUCTOR XT (combined lightning current and surge arrester with integrated life-check monitoring), DEHNvap DEHNguard

The challenge

With a track length of 533 kilometres, the high-speed line offers an ideal target for lightning. Damage is caused by direct lightning strikes and surges.

Direct lightning strikes cause electromagnetic interference sources, whereby coupling can take place via the overhead contact line, the rails and the masts.

Surges are mainly caused by switching operations and permanent interference voltages in adjacent line cables. With its highly sensitive electronics, modern signalling and control systems are particularly susceptible to faults.

Above all, it is important to avoid system breakdowns, because delays, train cancellations and necessary repairs cause high costs.

A comprehensive lightning and surge protection concept can significantly increase reliable availability even during thunderstorms.

protected.

The solution

This concept was planned and implemented directly by our colleagues at the DEHN branch in Istanbul.

It includes an isolated external lightning protection system with HVI technology for signalling and control system buildings, as well as comprehensive surge protection for the power supply and signalling and control systems. This ensures optimum terminal equipment protection, taking into account all system-specific conditions.

In particular, the protection of remote-fed audio-frequency track circuits – for the seamless indication of whether track sections are clear or occupied – was optimised. The powerful surge arresters of the DEHNvap, DEHNguard and BLITZDUCTOR XT series with monitoring function enable continuous status monitoring of the arresters and quick and easy testing without removing the modules.

This provides the ideal conditions for predictive maintenance.