Train control systems ensure that trains stop when they ignore signals or exceed permitted speeds. More than twenty different train control systems are in use across Europe. To ensure that cross-border train traffic can flow even more smoothly, the common European Train Control System (ETCS) standard will be replacing national solutions like the PZB and LZB— intermittent and continuous train protection systems, respectively. The Erfurt–Leipzig line is the first and currently only connection in Germany that already fully complies with all ETCS specifications.
The future ETCS wouldn’t work at all without Eurobalises. These small boxes are transponders installed directly on the track bed and are indispensible for vehicle positioning in the GSM-R—the Global System for Mobile Communications–Railway. The data they collect provide the foundation for all communication between signal boxes, trains and operations centers throughout Europe.
Today you can hear computers humming where previously the signalman used to throw the switches: the switch tower. Computer-based interlocking (CBI) makes it possible for the control centers to direct train traffic over long distances without any time delays. Multi-secured servers automatically control all the switching positions, but they can also be controlled by the operations center at any time. More than 330 CBIs are currently in use.
Safe and Sound
Engines and wagons must comply with countless DIN standards and laws before they are even approved as rail-worthy. After that, there are regular inspections so that they remain operational. Along with design elements including buffers, absorbers and reinforcements, which help secure the wagon interiors, the driver’s cab has yet another feature: a dead man’s control system known as Sifa. Train drivers must operate a button or pedal at least every thirty seconds, showing their ability to act. If this contact doesn’t take place, the train carries out an emergency stop.
The operations center in Leipzig is one of seven regional control centers that manage railway operations in their areas. The center that controls them all is the Network Management Center (NLZ) in Frankfurt am Main, which keeps a watchful eye on supraregional and international passenger traffic and a majority of the freight traffic. The operations centers oversee about 24,000 of the 38,000 kilometers of tracks in the German railway network and ensure that train spacing and timetables are adhered to. The rest will be covered by the main control center.
The sections of track inside tunnels are especially secured, with emergency exits allowing access to the outside in the event of any problem. Newer tunnels can switch off the overhead power lines, have access to radio communications with local authorities and have water for firefighting at the ready. The Finne Tunnel between Essleben-Teutleben and Bad Bibra is 6,965 meters long, the longest of the three tunnels on the Erfurt–Leipzig line.
Axle counters are an important part of the railway monitoring systems. Their sensors count the wagon axles at track entrances and compare them to the number counted at the track exit. The tracks won’t be signaled as free and clear for other trains unless the axle count number is identical.
Signaling systems were one of the earliest safety measures in the history of railways. With the gradual changeover to ETCS, the technology is moving from the tracks into the train. The Radio Block Centers act as the central interface between the train and the signal box. They continuously monitor the journey by radio, report all data to the train and issue the permission to travel on a stretch of track. They are an essential component of ETCS and replace the trackside signals.