Belgian railway signalling
Introduction '''Belgian railway signalling''' is the signalling in effect on the Belgian rail network currently operated by Infrabel.
Preamble Counter-flow track signal with a chevron and a speed restriction display (5 ⇒ 50 km/h). After this signal, the train will drive under normal track regime and cross back to the left track at 50km/hThere are in Belgium two types of train movement:* 'major movement' (e.g. mainline operation) that occurs during normal operation (traffic moves at the speed permitted by the signalling and regulations);* 'minor movement' (e.g. shunting) which is done by driving by sight and never faster than .The change from one movement to the other is done by signals (main stop signals) or a written order.The ''first movement'' (which is always executed as minor movement) happens in the following situations: * a driver taking over a new train;* a change in driver's cab or direction of travel;* receipt, change or removal of train number;* vehicles that can drive on themselves are coupled or uncoupled* when permission is needed to continue to drive after an incident* when beginning to shuntWithin major movement, there are two regimes, linked to bi-directional operation on double track lines:* ''normal track regime'': the signals are located on the left of the track. However, in some cases, the configuration of the environment precludes placing signs on the left track. They are then placed on the right and have an arrow (white arrow on a blue disc). * ''counter-flow track regime'': the signals are located on the right of the track and the aspects are blinking.The most common way of regime change is by the display of a chevron (V-shaped) sign on a main stop sign (single or combined).In ''minor movement'', all signals are to be obeyed, both those of the left hand track and the right hand; signals controlling  only minor movements are placed on the left. In counter-flow operation, some signals (light or otherwise) are specifically dedicated to minor movements and therefore are ignored by the trains travelling in ''major'' movement.
Light signals The lights are designed and arranged to be visible from a distance (up to two kilometers on a clear day). For this they are equipped with lenses to focus light rays emitted by the bulb, which can be selected and reasonable power. That is why the lights do not seem very intense when viewed from the side while they light up sharply in normal line of vision i.e. in the direction of arrival of the train.Note that the yellow lights often are orange in reality.=== Plain stop signal ===The red aspect requires a halt for both major and minor movements. It can be opened for major movement (green when the track gives access to a mainline, or double yellow in stations) or minor movement (red + white). It gives no information about the aspect of the next signal.A white number below the main aspect restricts the speed (from the first switch or track junction after the signal).Above the main aspect, the signal can show a chevron (to change the regime), or a "U" (when the train is led towards a dead end).It can be mounted on a mast or gantry (above the track).=== Warning signal ===Warns of the aspect of a following main stop signal:  It  can show a ''green'' aspect (the next signal is open without restrictions), ''double yellow'' (the next signal is at the stop aspect), ''green-yellow horizontal'' (the next signal requires a speed reduction) or ''green-yellow vertical'' (double warning in the case of a short section between the next signal and the signal after that, which has a red aspect or imposes a speed restriction).It may also present a yellow number above the signal with the main aspects green-yellow horizontal and green-yellow vertical and thus the speed (in tens of km/h) with respect to the next signal.=== Combined main stop signal ===Serves as both a stop signal and a warning signal and can therefore, according to the needs of the position, present aspects of both a plain stop signal and a warning signal. This type of signal is the most common one on the mainline network.=== Simplified stop signal ===It can either be placed at ground level or elevated (on a post). PhotoDescription  Simplified stop signal displaying 'halt' (red)  Red aspect: halt for trains in both major and minor movements. Simplified stop signal displaying 'track clear' (yellow)  Yellow aspect: allows trains in major and minor movement to proceed (but doesn't transform the movement type). It does not give any information about the aspect of the next signal.===Small stop signal===Triangle with a black base and two horizontal white lights The halt aspect applies only to minor movements. black triangle on base with two white lights placed diagonally to one another This aspect allows minor movement. It is placed on the ground.An older version of the small stop signal has the appearance of the simplified signal above, but with a purple instead of a red light.=== Completed operations indicator (IOT) ===The Completed operations  indicator is a system composed of a set of switches (activation) and light signals (display) on platforms of most stations and allows the guard to announce to the driver (conductor) that the procedure for boarding is completed and the train can start.Where the system is installed, the yellow aspect (or white on older systems) is a prerequisite for the departure of passenger trains.=== Aspects displayed by major stop signals and warning signals ===signals for left and right hand trackNormal operation (left hand track) ExplanationOpposite track operation (right hand track)70px or 30px''' Green''': allows the passage at full speed, the next signal 'track clear' without restriction or is a warning signal .Image:Signal sncb V CCV.gif or 30px 70px''' Double yellow''': allows the passage at full speed, but the next stop signal is set to 'line occupied' or switch to minor movements (Red White), or the signal does not "know" the state of the next signal. The driver must drive as if the next stop signal is a red signal.Image:Signal sncb 2J CCV.gif 70px or 30px'''Red''': 'halt'. If the signal is managed by a signal box, the driver cannot pass at danger without permission from the signal box.If the red signal is displayed on an automatic signal it warns for an occupied block section ahead or a level crossing that is experiencing technical difficulties. The driver will stop, write down the incident on his journey report and will proceed at sight. Image:Signal sncb R CCV.gif or 30px70px''' Green-yellow horizontal''': allows the passage at full speed, but the next signal requires a speed reduction. This speed may be indicated by number displayed on a yellow display at the top otherwise a black number on a white triangle can be affixed to the mast signal: it is the smallest speed that may be imposed by the next signal. If there is no indication, the driver considers that the imposed speed is . Image:Signal sncb VJH CCV.gif 70px''' Green-yellow vertical''': allows the passage at full speed and warns of a ''short section'': the distance between the signal following and that follows is shorter than the distance normally required to perform the action required .Image:Signal sncb VJV CCV.gif 70px or 30px''' Red and White''': allows the passage under 'minor movement' (change the type of movement if it was major movement ). The track behind the signal is occupied, dead end or the next signal is at 'halt' and is at abnormally reduced distance (<370 metres)Image:Signal sncb R+B CCV.gif or 30px
Signs === Speed signs ===PermanentExplanationTemporary  70px '''Announcement sign''': indicates a speed restriction ahead (in tens of km/h). The train has to slow down to this speed. 70px  70px '''Origin sign''': marks the beginning of a speed restricted zone. The number is the same as the announcement sign above. Sometimes the number is not present and a plain black circle is used instead. 70px  70px  70px  '''End of zone sign''': after passing this sign the train can accelerate to the speed indicated (in tens of km/h). * The version shown above is used when the speed limit is less than the reference speed limit of the line. * The version shown below may be placed between an announcement sign and an origin sign to allow acceleration when another track with a lower speed limit joins the track that had the announcement sign. 70px  70px   70px '''Reference speed sign''': after passing this sign the train can accelerate to the reference speed limit of the line, which is the speed indicated (in tens of km/h). 70px  Additional  panels (''special'' triangles, for example) are used to indicate that only certain types of trains are affected: e.g., "HKM" means the sign only concerns freight trains .===Some other signs===ImageExplanation  35px '' 'Control reference line''': indicate on what line it is headed. 45px ''Catenary end sign:  indicates the end of the zone powered by overhead wire. Electric trains must halt.'' 57px '' 'Expect lower pantograph''': Warns of upcoming 'lower pantograph' signal. 55px'' 'Lower Pantograph''' 15px '' 'Raise pantograph''': end of zone in which pantograph(s) had to be lowered.
Other signals DetonatorOther signals complement the fixed signs: * Mobile signals (light at night / low visibility, flag day) red, yellow and green;* Acoustic signals (detonators, horns);* Torch flame red lights flashing (requiring 'halt');
Cab signalling A main stop signThe TBL1+ system was designed in 2006 by the Belgian subsidiary of the Alstom Transport group. This is the new standard for Belgian signalling, supposed to be deployed on most lines equipped with conventional signalling. The signals are the same as classic ones, but they are combined with automatic train control and cab signalling.The trigger for developing this system was the Pécrot disaster in March 2001 when two trains collided head-on because a driver had passed a red signal, highlighting the finding that the majority of lines, no system prevented the train from passing a stop signal. It was therefore decided to invest in such a system.At the time, however, the existing TBL1 system offered this feature of automatic stop at red lights, but only a few main lines were equipped (or approximately 13% of signals). NMBS/SNCB decided therefore to abandon this TBL1 system and modified to make it compatible with the new European ERTMS standard in terms of ground infrastructure, becoming the system TBL1+.Today, the TBL1+ system is undergoing testing and certification. It will be installed from 2008, the objective being to equip the entire network by 2013. '''Status of introduction of TBL1+''' District Railway line Route section Junction Centre 26  Huizingen 96 Ruisbroek - Lembeek All junctions 96 (track B) Bruxelles Midi - Forest All junctions North East 29  Grid Tielen North West 50 A Oostkamp-Beernem All junctions 50 A  Switching zone Oostkamp Switching zone Beernem South East 124 Roux-Luttre All junctions 132  Yves-Gomezée=== Basics ===The TBL1+ system is a system of driving aids to repeat the signals aspects in the cab, and to intervene if the driver does not comply with the directions given by these signals. Unlike systems such as ERTMS TBL2 which supervise a speed curve, the TBL1+ system does only  a spot-check when passing light signals. This is done with a beacon placed in the track, which transmits to the onboard computer a message containing the signal aspect. We can classify the appearance of a signal into three broad categories:=== Clear aspect ===This aspect indicates that the track is clear and allows the train to run at maximum speed allowed. This is typically a green signal. When the train passes a signal as the TBL1+ system simply repeats information and makes a short sound in his cab (the lamps used to indicate a possible restriction are also extinct).=== Restrictive aspects ===This type of aspect requires the driver to slow, for example, because the next signal shows a non-clear aspect (double yellow) or imposes a speed limit (yellow-green horizontal).When the train passes a signal as the driver must confirm that he saw the signal by pushing a button, otherwise the system will apply the emergency brake. In addition, a yellow lamp is lit in the cabin to remind the driver that runs under a restrictive regime.=== Stop aspect ===This type of aspect (typically a red signal) instructs the driver to halt and can not be passed by a train (except with a special procedure).If the train passes a signal showing a stop aspect, the TBL1+ system immediately applies the emergency brake and flashes a red light in the cab, forcing the train to stop completely and as quickly as possible.Although TBL1+ does not control the speed curve, the system does include a reduced speed control. In this mode, indicated by the "V  40" displays indicate whether the TBL1+ system is in "control of low speed" or not. The manual shift mode to another is done by pressing the corresponding LED. The button permits temporary disablement of the system, following a strict procedure, temporarily disabling the system to pass signals in such trouble.The onboard computer is connected to an antenna to read ERTMS tags placed in the path, and a brush-crocodile to capture the information transmitted by crocodiles in the track.A recorder is also on board the train to keep track of signals encountered and the actions of the driver.=== Other cab signalling systems ===*TVM 430 on the line 1 *TBL2 on the Line 2 and *ETCS levels 1 and 2 on the line 3 and Line 4
References * signalisation* Belrail.be guide to signals * Wallorail.be guide to signals *HLT Booklet of the NMBS/SNCB (Rules for train drivers)**
External links *  Cab view video Forest to Lille with signals explained