ERTMS: a railway security system

Although it is a complex system, ERTMS has become imperative to ensure traffic safety and rail traffic management.

The European Rail Traffic Management System (ERTMS) is an EU “major European industrial project” to enhance cross-border interoperability and signalling procurement by creating a single Europe-wide standard for railway signaling with the final aim of improving the competitiveness of the rail sector.
ERTMS has two basic components: ETCS, the European Train Control System, is an automatic train protection system (ATP)to replace the existing nationalATP-systems; GSM-R, a radio system for providing voice and data communication betweenthe track and the train, basedon standard GSM using frequencies specifically reserved for rail application.

Interoperability Directive
On July 23rd 1996 the Interoperability Directive 96/48/EC was issued by the European Commission. It outline the rules, defining the structural nature subsystems (infrastructure, energy, signalling, remote control, etc) and functional nature subsystems (maintenance, control of environmental impact, exploitation constraints, etc), as well as the basic constituent components of said subsystems in order to allow rolling stock from one country to run in another EU State’s lines with absolute guarantees of efficiency and protection.
The European Commission desires to revitalise the railway sector eliminating technical barriers for interchanges and train interoperability (for example, its capacity to circulate indistinctly in all railway networks). This favours the integration of the European Railway Network, simultaneously guaranteeing higher security levels and lower costs.
Europe has more than 20 different signalling and speed control systems in rail transport. These are locomotive-integrated onboard systems with collection systems that react to signals transferred from the ground.
These systems are expensive, but essential for security and railway traffic management.
The coexistence of various models constitutes an obstacle to the development of international railway traffic, since locomotives must be able to ‘read’ signals from different networks when crossing borders. The Thalys train, which links Paris and Brussels, has seven different on-board systems, with the according increase in costs and failure risks, and the major headache for drivers, who have to be able to handle all the different interfaces. Furthermore, this segmentation represents a limitation for the integration of railway transport at a European scale, while road transport takes advantage of the absence of barriers.

On-board equipment
The European Commission published on July 4th 2005 a Communication on the deployment of the European system for rail signalling ERTMS/ETCS. On this basis, the Commission defends the gradual adoption of a common system for all EU Member States with the European Rail Traffic Management System (ERTMS).
The equipment necessary for the operation of the systems is divided into two parts, on one hand there is the on-board equipment and on the other the external equipment. On-board equiped is composed of: an antenna installed on the underside of the train and that is responsible for the communication between the on-board and trackside systems; an antenna installed on the roof of the train (optional, only if radio communication is used) for voice and data communications between on-board and trackside systems; EURORADIO: receives ERTMS voice and data from the antenna; BTM (Balise Transmission Module) device that allows the reading of the track installed balises. Its function is to receive the underside-antenna messages and make them easy to handle for EUROCAB; EUROCAB: core of the system. It processes all the information proceeding from the antennas, supervising train movements and controlling the information shown to drivers in the DMI (Driver-Machine Interface) and the information sent to the JRU (Juridical Recor ding Unit), taking action on brakes if necessary. EUROCAB continuously calculates the train’s position by means of its own odometer based on Doppler radar sensors and wheel sensors; DMI: it presents all relevant data to drivers, such as current speed, speed limit, speed restric tions, breaking distance and text messages.

Trackside equipment
Composed of: Blocking elements: electronic devices that control each station. They are used to determine routes, signalling aspects and position of switches; track circuits: detection of the train’s position, transferring it to the blocking elements; LEU (Line-Side Electronic Unit): they convert the information received from the blocking of the station in ERTMS telegrams which they then send to the balises.
EUROBALISES: they transmit telegrams with information relative to train control and traffic operation that are transferred from the LEU to the train.
RBC (Radio Block Center): it’s connected to the blocking elements when data communication via radio is used to transmit
ERTMS telegrams to the train.
GSM-R: transmission system for voice and data via radio used by the ERTMS.

ERTMS levels
Level 1.
The operation of the system as a Level 1 is based primarily on the interlocks, providing information on the status of the needles, signals and routes to the LEU (standard electronic units), encoding information and forwarded to the eurobalises located in the rail.
At level 2 ERTMS, the blocking of trains is done from a Radio Block Centre (RBC), which receives the information, on one hand from the interlocks and on the other hand it transmits the information to trains through the GSMR system.
At Level 3, the train integrity data are sent via a separate system on the composition, therefore track circuits are not required, as in the previous level. This allows the cantons to be mobile.

Spain and ERTMS
Under the strong leadership of infrastructure manager ADIF, Spain has embarked on a major program of railway investments, identifying ERTMS as the signalling system of choice. The first contracts were signed in the early 2000s and ERTMS now covers the major part of the Spanish High Speed network.
At present, the following major lines are running using ERTMS: Madrid – Zaragoza-Lleida (442 km), by Ansaldo technology; Lleida-Roda-Barcelona (183 km), by Siemens technology and Simenes eurobalises; Barcelona- Sants-Mollet, 20 km, Mollet- Figueres, 112 km, byThales technology and Siemens eurobalises; Zaragoza-Huesca, 73 km, by Alstom technology; Madrid- Segovia-Valladolid, 179 km, by Thales technology and Siemens eurobalises; Córdoba-Málaga, 155 km, by Dimetronic-Invensys technology and Siemens eurbalises and LZB of Thales; y La Sagra – Toledo, 21 km, with LZB de Thales, commuter rail Madrid C-4, Parla-Colmenar Viejo/Alcobendas- San Sebastián de los Reyes; and the by-pass de Torrejón de Velasco; y Ourense-Santiago, 87 km, with Thales technology y Siemens eurobalises.

Last news
The ERTMS2012.EU Conference was held in Copenhagen on April 16 and 17, during which the new version of the European Rail Traffic Management System, ERTMS – Baseline 3, was presented. Over the course of this conference, hosted in Denmark, the country that holds the European Union’s rotating presidency in this six-month period, the European Railway Agency, ERA, delivered to the Commission this new version of the ERTMS so that its Risk Committee can submit it for approval to the member States in preparation for its adoption into law.
This presentation was formalized through the signing of a Memorandum of Understanding concerning the strengthening of cooperation for the management of ERTMS.

Baseline 3
The new version of the ERTMS- Baseline 3, is a huge leap forward in the system since it addresses practically every issue that remained in previous versions, including a key point like braking in curves. It is also backwards compatible with previous versions of the system, such that a train equipped with Baseline 3 can travel without any problems on a line with the previous version, 2.3.0.d.
Spain’s essential role in the deployment, development and success of the ERTMS was made evident at the conference, as Spain has been an international benchmark in demonstrating the proper operation of the system. The conference made it clear that the ERTMS has become a world standard in railway signaling, since more than half of the projects contracted with ERTMS are outside of Europe. European industry has thus become a world leader in advanced railway signaling systems, and provides a clear example of the success being enjoyed by this European Commission initiative.

More than 5,000 km in contracted services by Mafex companies worldwide (more than 2,900 outside Spain)

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