Railway signals in Germany

Pre- and main signals (form signals) of a train station with the signal terms Hp 0 on the main signal and Vr 0 on the distant signal

Railway signals generally signal whether and at what speed sections of the route may be traveled. There are various types of signals for this purpose, which can be roughly divided into main and distant signals as well as additional signals .

In Germany, the Eisenbahn-Signalordnung (ESO), in which the meaning of signals is regulated, is part of railway law because signals are very important for operational safety. The practical application is described in the signal book . The message displayed by the signal is often referred to as a signal , signal aspect or signal aspect .

development

Signal images main signal: Hp 0: stop, Hp 1: drive, Hp 2: slow travel
Signal images advance signal: Vr 0: expect stop, Vr 1: expect travel, Vr 2: expect slow travel

Combination signals (Ks)

After each railway company had its own signaling system in the early days of German railway history, the extensive nationalization of these companies from 1875 resulted in a uniform signaling system for the railways in Germany . Even before that, there was extensive production of railway signals, such as in 1873 at the Max Jüdel & Co railway signal construction company .

Shape signals with panels of different geometrical shapes are still widely used today. In addition to the terms stop (Hp 0) and travel (Hp 1), some of the main form signals also allow the term slow travel (Hp 2). Show formal pre- signals expect stop (Vr 0) expect travel (Vr 1) and expect slow travel (Vr 2). Shape signals with wings were initially called semaphores . At night, these signals were accompanied by lights in different colors: Until 1907, "Drive" (Hp 1) was signaled on a main signal with a white light, "Stop" (Hp 0) with a red light and turnoff / slow travel (Hp 2) with a white and a green light. In the case of pre-signals, the green light meant “expect stop” (Vr 0), while a white light meant “await travel” (Vr 1). The disadvantage of white light was that it could easily be confused with other white light sources and led to a number of accidents . After several unharmed accidents, the signaling order was therefore changed. By 1913, almost all German railway administrations had replaced the white light with the green light, which is still in use today and which could not be easily mistaken. The only exception was the Royal Bavarian State Railways , which shied away from the cost of retrofitting. Until 1919, only one line there was equipped according to the new regulations and the railway accident in Nannhofen , Bavaria, on April 17, 1917, in which 30 people died, was precisely due to such a signal mix-up.

At the end of the 1920s, signals were introduced on the Berlin S-Bahn that showed the signal terms not via the shape, but exclusively via colored lights. The so-called Sv signal system is still in use today on the Hamburg S-Bahn . Sv stands for signal connection, because these signals combine the main and distant signal function (multi-section signal). In Berlin (East) it has been replaced by the Hl system since the 1980s in the course of long-distance rail electrification, in the western part and partly also in the eastern part of Berlin it has been replaced by the new Ks signal system.

For the mainline railways, initially in the Federal Republic of Germany until 1994 and since then also for Germany as a whole, the Railway Signaling Regulations (ESO), which have been in force since 1959, contain the specifications for the signals to be used in accordance with Section 14 of the Railway Construction and Operating Regulations . The signals used by DB AG are listed in the signal book of Deutsche Bahn AG (guideline 301).

Based on the night signals of the form signals, the German Federal Railroad introduced the H / V light signals after the Second World War. Apart from the train stop and maneuvering ban (Hp 00) signal, the number of signal aspects did not differ from that of the form signals.

The Deutsche Reichsbahn developed the independent HL signal system . HI signals are multi-section signals (see below). HI signals indicate three speed levels in addition to stop and drive .

The Deutsche Bundesbahn also experimented with multi-section signals and installed the Sk signals on the Augsburg - Donauwörth line on a trial basis. They later became the conceptual basis for the combination signals (Ks) that have been used in new buildings and renovations throughout Germany since the mid-1990s. Ks signals are now in use on most main lines. In connection with speed indicators (Zs 3) and speed previews (Zs 3v), they allow the additional signaling of maximum permitted speeds in 10 km / h steps.

Since trains have a comparatively long braking distance, it is important for train drivers to be informed as early as possible whether and at what speed the next section of the route can be traveled. For reasons of cost, this information should be conveyed as simply as possible. Light signals open up the possibility of giving information about two route sections on just one signal carrier with just one light point. For comparison: with form signals, two independent and therefore expensive mechanical signals are required. Shape signals are generally no more susceptible to interference than light signals, but their mechanics mean that they require significantly more maintenance.

Deutsche Bahn assumes an average operating time between signal failures (including their interface) of 182,000 hours and an average downtime (MDT) of two hours.

Signaling systems

Since the beginning of the railway age, there have been a wide variety of signal systems in Germany, and almost every railway company had its own signals. Since the merger to form the Deutsche Reichsbahn, uniform signals have been used throughout Germany. Nevertheless, in addition to the H / V system developed in the 1920s, other different systems are or were in use that were only tested as operational trials or were limited to certain areas of application. The Ks system will be installed on all new and upgraded routes and will replace all other signal systems in Germany in the future.

H / V: The H / V signal system that was created at the time of the Länderbahn and the pre-war Reichsbahn knows separate signal aspects for main and distant signals. Form signals are an outdated standard throughout Germany. H / V light signals were standard in the area of the former Bundesbahn, in the area of the former Reichsbahn they only occur occasionally. The H / V system is being replaced by the Ks system.

St.: HI signals enable multi-section signaling with light main and light signals. They were standard in the area of the former Reichsbahn. Hl and Hf were the conceptual differentiation of light signals and shape signals at the Deutsche Reichsbahn. The Hl system is replaced by the Ks system.

Sk: In 1977, the test operation of the multi-section-based Sk system (Sk for signal combination) was started in the area of the former federal railway on the Augsburg – Donauwörth line. It could not prevail and will be replaced by the Ks system in the future.

Ks: Ks signals enable multi-section signaling with combination signals (light signals) and are the new all-German standard. They are mainly based on the merging of the Sk and Hl systems.

Sv: On the S-Bahn in Berlin and Hamburg, Sv signals were used as signal connections with multi-section signaling. In principle, they are similar to the H / V system with up to four light points arranged in a square. This signal system only exists in Hamburg, the Berlin S-Bahn has replaced these signals with Ks signals.

Ho: Ho signals (main signals without distant signals) were designed in 1949, but never put into operation. You should be able to indicate the absence of up to three blocks on a main signal without the use of pre-signals. The Ho signal screens manufactured at that time were later used for the Ma signals.

Ma: Ma signals (multi-section signals) were tried out as operational trials in Cologne from 1951 to 1959. The system was not adopted in practice, but replaced by the H / V system.

DR-Ma: The signal connections for long-distance railways were operated in 1955 as self-block signals on the Berlin outer ring. From 1959 they were referred to as multi-section signals (DR-Ma), in 1962 these were replaced by HI signals according to the OSJD standard.

Deutsche Bahn operates around 262,000 light signals.

Signal types

Main signals

KS signal at Munich East station

Main signals (Hp) indicate whether a train is allowed to enter the following route section or not. A distinction is made between entry , intermediate and exit signals in train stations, block signals on open routes, which allow a closer train sequence, and cover signals infront of danger spots.

Main signals - with the exception of Hl, Sk and Ks signals - can display up to three signal aspects:

Hp 0 (stop): You must stop before the main signal. The following block of the route is occupied or the journey ends here. If the journey is to be continued anyway, special measures must be taken to continue the journey ( command , additional signals , etc.).
Hp 1 (drive)

The main signals in the H / V system are shape or light signals. Form signals have one or two signal wings as day signals and one or two lights as night signals. The light signals of the H / V system correspond to the night signals of the form signals.

Main shape signals can be the signal aspects Hp 0 (one wing horizontally to the right, at night a red light), Hp 1 (one wing diagonally upwards to the right, at night a green light) and / or Hp 2 (two wings diagonally to the right upwards, at night a green one Light and a yellow light below). Main light signals in the H / V system can show the signal aspects Hp 0 (red light), Hp 1 (green light) and Hp 2 (green light, a yellow light vertically below). Occasionally, main signals are also used that cannot indicate a concept of travel, called main signals with no concept of travel (also destination signals or blind signals). They mark the point where a train journey always ends, but a protective signal (Sh 2) is not conspicuous enough to signal this.

The masts of the main shape signals are equipped with red and white striped mast plates for better visibility. These are of no relevance for driving duties. Main light signals are identified by mast signs, which regulate the behavior of the driver in the event of a stop or a disturbed signal.

Sk and Ks main signals with distant signal function are marked with a distant signal mast sign. Since 2007, HL main signals, which also have an advance signal function, have been equipped with such advance signal mast signs.

Pre-signals

Expect distant signal in braking distance shortened by more than 5% or distant signal repeater with signal aspect Vr 0 stop

A distant signal (Vr) announces the signal aspect that can be expected at the associated main signal. In special cases, it can also be a stop pointing barrier or protection signal ( Sh 0 or 2 Sh announce).

The announced signal usually follows at the distance of the braking distance. The braking distance can vary depending on the route; it is generally 1000 meters on main lines and 700 or 400 meters on secondary lines. A braking distance shortened by more than 5% is specially indicated on the distant signal.

If the prescribed visibility of a main signal (depending on the permitted line speed up to 500 m) cannot be established or if there is a risk of signal mix-ups due to overlapping lines of sight on tracks running parallel in a curve, the signal image of the distant signal is repeated once or several times by repeater. The location of the distant signal repeater is to be selected so that it is visible from the point from which the associated main signal would otherwise have to be seen. Distant signal repeaters are always light signals. The repetition of the distant signal also prevents unnecessary braking of the train when a stop has been announced and the main signal has meanwhile come into the running position. If there is a stopping place between the distant signal and the main signal, a repeater at the end of the platform informs the driver of the position of the main signal even during the stop, if this cannot be seen from there.

In simple conditions (for example on branch lines), instead of a distant signal, only a distant sign - in the area of the former Reichsbahn, a cross sign - can be set up until further notice. They almost correspond to a distant signal in a warning position.

Other signals

Symbol on control pillars in train stations for Zp9 light signal

Control column for the train crew with Zp9 signal.

Additional signals (Zs) provide the driver with additional information about the route ahead, which cannot be expressed by main signals alone. Fixed additional signals are usually attached to the mast of a main or distant signal.

The speed indicators, which indicate the permissible speed for a route section contrary to the book timetable, are very frequent additional signals. There are also additional signals for special situations that permit the passage of main signals that indicate a stop or that are disturbed, or that announce the use of the opposite track.

Slow travel signals (Lf) are located on sections of the route where the permissible speed is permanently or temporarily reduced (e.g. due to damage or construction work).

Protection signals (Sh) give stop or drive orders. These can be stationary signals, but they can be e.g. B. in case of danger can also be given by signal flag, lantern or horn. Historically, crack pods laid out on the rails were alsoused.

Secondary signals (Ne) indicate, for example, at what distance a distant signal can be expected, where a train should stop in the station, if a main signal is not to the right of or above the track or which distant signal is really a distant signal and which is only a repeater.

For shunting trips, special regulations and shunting signals (Ra) apply , some of which are stationary, some of which are given by the shunting manager to the driver of the shunting locomotive.

Turnout signals (Wn) used to be on almost every turnout, but have become increasingly rare today. This is due to the fact that with the introduction of shunting routesin the relayinterlockingssince the 1950s, shunting trips always start and end with a protection signal. If there are no shunting routes, changing the first switch in front of a shunting unit counts as a shunting order.

Signals for the train crew (Zp) are, for example, departure signals and brake test signals .

Contact line signals (El) report short sections that electric traction vehicles can only pass through when the power supply is switched off and at sufficient speed. The end of the overhead line is also announced with these signals.

The train signals (Zg) and vehicle signals ( Fz) include the identification of a train at the front ( triple headlights ) and at the end ( end of the train ), the identification of a shunting unit and the identification of parked wagons that are occupied by people.

Level crossing signals (Bü) show the driver u. a. whether the level crossing is secured, where the switch-on point of the safety devices is, or where it has to give a whistle signal.

Rotten warning signals (Ro) apply to people working on or near the track and give instructions on how to behave when vehicles approach. Ro signals are acoustic signals that are given with the multi-tone horn.

Signals for push-pull locomotives and blocking trips (Ts)

literature

Federal Railway Directorate Hanover: 1843–1983. 140 years of the Hanover Railway Directorate. Hannover o. J. (1983), page 81ff.

Erich Preuß : Signals of German Railways , Transpress Verlag, Stuttgart, 1998.

Signal = rarities = cabinet in the magazine DREHSCHEIBE

Miba Report, Signals , Vol. 1,2,3

Web links

Commons : Railway signals in Germany - collection of images, videos and audio files

stellwerke.de - Signal system Germany, every signal with picture
Signals in Germany, DRG, DR and DB at www.bahnstatistik.de
blocksignal.de - Interesting previous signal technology projects . Pre-war light signals in Germany, Sv signals and others
Signal systems in Germany (English)

Individual evidence

↑ Hans-Joachim Ritzau: From Siegelsdorf to Aitrang. The railway disaster as a symptom - a study of the history of traffic . Landsberg 1972, p. 108.
↑ Study on the introduction of ETCS in the core network of the Stuttgart S-Bahn. (PDF) Final report. WSP Infrastructure Engineering, NEXTRAIL, quattron management consulting, VIA Consulting & Development GmbH, Railistics, January 30, 2019, p. 269 , accessed on April 28, 2019 .
↑ Deutsche Bahn converts signals to LEDs. In: sueddeutsche.de. February 28, 2017. Retrieved August 13, 2017 .
↑ BGBl. 1986 I p. 1012

[1] Hans-Joachim Ritzau: From Siegelsdorf to Aitrang. The railway disaster as a symptom - a study of the history of traffic . Landsberg 1972, p. 108.

[abschlussbericht-2019-01-30-2] Study on the introduction of ETCS in the core network of the Stuttgart S-Bahn. (PDF) Final report. WSP Infrastructure Engineering, NEXTRAIL, quattron management consulting, VIA Consulting & Development GmbH, Railistics, January 30, 2019, p. 269 , accessed on April 28, 2019 .

[sz-2017-02-28-3] Deutsche Bahn converts signals to LEDs. In: sueddeutsche.de. February 28, 2017. Retrieved August 13, 2017 .

[4] BGBl. 1986 I p. 1012