Developing safety systems
If you often travel by train, you have probably seen the signal lights and signs along the tracks. These give instructions to the train driver so that he can drive the train safely from A to B. However, because to err is human, Infrabel is installing additional safety systems on the railways.
1. A dedicated mobile telephone network for the railways
For a train to travel safely from A to B, the driver and Traffic Control must be able to communicate with each other. For this reason, Infrabel has installed its own dedicated GSM network along the tracks – GSM-R. This means that train drivers never lose contact with Traffic Control.
Via GSM-R, Traffic Control not only communicates verbally with the driver, but can also transmit signal information with which the driver must comply. GSM-R has been in use across the entire rail network since 2010.
2. Driving support systems: TBL1+
In Belgium there are currently three different support systems, which have been developed to work in harmony alongside each other:
- Memor-Crocodile, since the 30s
- TBL1, since the 80s
- TBL1+, since 2005.
These safety systems work only when both the rail infrastructure and the train itself are equipped with them.
How does it work?
The TBL1+ system (= Transmission Beacon/Locomotive 1+) consists of a beacon placed in the track that emits an electromagnetic signal. This signal is received by an antenna underneath the driver's cab. When the driver approaches a red signal, the support system activates a light in the cab. The driver must then acknowledge that he has received the warning by pressing a button.
What happens if he does not do so? The emergency brake is automatically activated. This also happens if the driver has acknowledged the warning, but the train is still approaching the red signal too fast. If the train is still travelling at more than 40 km/h when it is 300 metres from a red signal, the device automatically stops the train. So, thanks to TBL1+, the risk of passing a red signal is greatly reduced.
The equipment used for TBL1+ is compatible with the European ETCS system. Switching over from TBL1+ to ETCS requires only a simple modification.
WHAT IS EFFECTIVE COVERAGE?
By using the TBL1+ system, 75% of the situations where a train is placed in danger can be prevented. These are the situations where one train can encounter another train on its track, for example where two tracks intersect, or at switches that connect two tracks with each other. We can therefore claim that TBL1+ provides 75% risk cover.
There are more than 10,000 signals on the Belgian railway network. Some signals are "riskier" than others. For example, a signal that is located just before a rail junction with switches, where two tracks cross each other, is "riskier" than a signal that is located alongside a track without any switches. Based on a number of parameters, every rail junction on our railway network is given a score.
These parameters include:
- the presence of switches
- the presence of a stopping point, where a train may be standing still
- the number of trains using this line
- the number of passengers travelling on this line
Equipping junctions resulted in an effective coverage of 99.9% at the end of 2015.
In line with the above approach, and by analogy with our neighbouring countries, certain signals have not been equipped with TBL1+. These include, for example, signals alongside freight lines, or passenger lines that do not meet the above criteria. As a result, a total of 7,573 signals were equipped with the TBL1+ system over the entire Belgian railway network, which works out at approximately 70% of the total number of signals in Belgium.
3. ETCS: the European Train Control System
How does it work?
The European Train Control System (ETCS) is an automatic train control system that informs, monitors and corrects with the aid of balises (beacons) in the track and a computer system in the driver's cab.
The balises on the track detect the precise location of the train so that the maximum permitted speed can be calculated. They also send the necessary route information to the on-board computer on the train.
The ETCS system will also monitor the train driver, and take corrective action if necessary. If, for instance, there is a red signal two kilometres further along the track, the ETCS system will ask the driver to slow down. If the driver does not keep to the maximum speed limit , does not brake in time or passes through a red light, the system automatically corrects the speed of the train or activates the emergency brake.
The European standard
At any speed higher than 160 km/h, the train driver can no longer see the signals along the tracks and needs to have the information on board the train.
ETCS is already mandatory on high-speed lines. Since ETCS is a European standard, Infrabel is in the process of installing the system on the standard rail network as well. That means that trains with ETCS and which travel through different countries no longer need to have different signal systems on board. This, of course, improves interchangeability within rail networks in Europe.
ETCS has so far been installed on:
- the Brussels-North – Leuven line;
- the Schaerbeek – Mechelen line;
- the Diabolo rail link (to and from Brussels National Airport);
- the Mechelen – Leuven line, between Hever and Wijgmaal.