Punctual train control

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Track magnet for punctual train control (Siemens, small design)
Track magnet (GWT, 500 Hz, below) and vehicle magnet (Siemens, above)

Point train control ( PZB ) refers to different systems of train control that allow monitoring and control of rail-bound vehicles at selected points on a rail route. In the systems currently in use, it is mainly monitored whether a signal indicating a stop has not been exceeded, whether speed restrictions are being observed and whether the driver perceives signals restricting travel and acknowledges them by pressing the vigilance button. The current German system PZB 90 is based on the Indusi system introduced in 1934 in three-frequency resonance design.

The respectively applicable restriction or information is transmitted to the vehicle at certain points by oscillating circuits on the track (so-called "track magnets") and evaluated by the vehicle equipment. If a restriction is disregarded or inattentive, the vehicle equipment triggers an emergency brake. Overriding interventions by a PZB system is partially possible and necessary for the continuation of operations. These interventions are registered by the vehicle equipment.

Train control systems that operate at points only monitor compliance with signaled restrictions and the attention of the driver. They close the security gap between signaling and the vehicle, for which the driver is otherwise solely responsible without technical support. You cannot and should not check whether the applicable restrictions are sufficient. For example, they cannot determine whether a section of the route behind a signal indicating the traffic or a signal in the stop position, which is driven over with permission and temporarily bypassing the PZB, is really free. Originally, the punctual train control was supposed to work in a concealed manner and, at least with unrestricted driving concepts, not require any additional operator actions by the locomotive crew, but this principle could not be maintained.

Point-shaped train control systems can be installed on the track and vehicle side parallel to other train control systems. In the case of linear train control (LZB), the PZB serves as a fall-back level, since all vehicles with LZB in-vehicle equipment also have PZB equipment. As part of the introduction of the European Train Control System (ETCS), PZB is a class B system that enables double equipment on routes with ETCS level 1 or 2. In both cases, the PZB only works for vehicles that do not have any LZB or ETCS equipment or as a fall-back level during and after transmission failures.

At the end of 2019, 32 398 of the 33 291 km operating length in the Deutsche Bahn network were equipped with PZB, and the number is rising.

PZB 90

The currently used in Germany, point-acting automatic train control system is a microprocessor- controlled variant of the name Indusi introduced in Germany in the 1930s form the inductive punctual train control. According to the operating program , this form of train control is called PZB 90 . Compared to the previous versions, the operating program of the PZB 90 has undergone important extensions. The system consists of track and vehicle equipment.

PZB 90 or its predecessor types are also used in Austria , Romania, Israel , Turkey and the successor states of Yugoslavia.

Similarities with previous versions

Vehicle magnet of a test design on the tender of a steam locomotive (1930)

The main task of the PZB is to prevent unauthorized driving past a signal indicating a stop by means of emergency braking . The system is not only used for advance and main signals , but also for level crossing monitoring signals , blocking signals or entrances to butt tracks . Another application of the PZB is the monitoring of the permitted speed in front of a danger point on the route by means of a speed test section .

The track equipment consists of 1000 Hz track magnets, for example at the locations of speed indicators , monitoring signals, pre-signals and slow speed discs, 500 Hz magnets, for example 150 to 300 meters in front of main signals (generally 260 meters) as well as at slow speed points and 2000 Hz magnets for example on blocking signals and on main signals as well as in speed test sections . Double track magnets for 1000 and 2000 Hz are installed at the location of main signals, which may contain pre-signaling. The vehicle magnet contains three oscillating circuits for 500, 1000 and 2000 Hz, each of which generates an electromagnetic alternating field that induces a voltage in the oscillating circuit when an effective track magnet is driven over . Mutual induction causes the quiescent current of the relevant frequency to drop in the vehicle's resonant circuit, which triggers a reaction in the vehicle device. When the signal is moving, the oscillating circuits of the track magnets are short-circuited and thus detuned so that no effect is triggered in the vehicle device.

Introduction and distribution of the PZB 90

After several serious accidents, the PZB 90 system was introduced in the mid-1990s through a further development by Indusi. In the narrower sense, PZB 90 is just an operating program that was partially implemented through modifications to the existing Indusi vehicle devices I 60 or PZ 80 (see also: Indusi: Further development ).

In spring 2011 there were around 4200 route kilometers in the Deutsche Bahn network without PZB route equipment; 80 percent of them were in the network of the former Deutsche Reichsbahn . At that time, various sources reported a need for 500 to 800 kilometers of route that had yet to be equipped. This did not apply to many lines operated by train control .

After the railway accident in Hordorf , the last gaps were closed in 2012.

The track equipment has been supplemented by further equipment with 500 Hz magnets, which are now usually 260 meters (until 2018: 250 meters) instead of 150 to 200 meters in front of the main signal location as was previously the case. If there is a permanently free control protection section of 450 meters behind a main signal, the installation of a 500 Hz magnet is still not necessary. This also applies to block signals if the distance to the following is greater than the maximum permissible train length plus 450 meters.

Track magnets and track magnet holders are available from several manufacturers, each of which supplies its own types. Electrically, they are equivalent and, if approved in the respective country of use, can be interchanged, regardless of the interlocking design. For the 1000 and 2000 Hz influences, only double track magnets are produced; they can be switched with bridges to be inserted or by control contacts. Existing single track magnets can still be used.

The compensation for the standard rail inclination of 1:40 is incorporated into the track magnet holder. For installation on vertical rails in switches and crossings or the now only a few track sections with the old track inclination of 1:20, there are aluminum spacers with a wedge-shaped cross-section.

Operating program

PZB 90 operating program PNG
Arrangement of the PZB indicator lights
The three PZB buttons on an ICE T.
Indicator block EZ155, speedometer and below that buzzer on a steam locomotive
Siemens I60 / ER24 switch housing with control buttons on a steam locomotive

The operating program has undergone important extensions compared to the original Indusi.

1000 Hz speed monitoring

After influencing a stop or a strong reduction in speed, a main signal with pre-signaling or a monitoring signal from a level crossing safety system, the alert button must be pressed within 2.5 seconds (for newer vehicles with MV bus , 4 seconds for old systems) otherwise an emergency brake is triggered. This is followed by a type of train and time-dependent speed monitoring (V ü1 ), which, unlike the old Indusi I60R / I80, only works once after 700 meters after the influence, but rather simulates a braking curve to be driven under. After 700 meters, the monitoring speed remains constant, without any further influences it continues to run up to 1250 meters after the influence. The type of PZB-90 train depends on the braking ratio ( braking percentage ):

Because the speed monitoring is not only punctiform, but is more or less continuous through braking curves , the test speeds were tightened with software version 1.6 compared to the Indusi. Lower speeds and later points in time at which these speeds must not be exceeded have been specified.

Trains, the switching speed V by a 1000 Hz influence during more than 15 seconds to fall below h of 10 km /, thereafter on the restrictive speed of 45 km / h (V u2 monitored). A train that stops between the pre-signal and the main signal is therefore subject to the restrictive monitoring function.

Key data of the various speed monitoring curves on the 1000 Hz magnet depending on the type of train:

PZB-90 train type Brake hundredths normal speed monitoring V ü1 restrictive speed monitoring V ü2 Switching speed V to
O over 110 from 165 to 85 km / h in 23 seconds constant 45 km / h constant 10 km / h
M. 66 to 110 from 125 to 70 km / h in 29 s constant 45 km / h constant 10 km / h
U under 66 from 105 km / h to 55 km / h in 38 s constant 45 km / h constant 10 km / h

This table is only valid in the P / R braking positions; in the G braking position, the PZB train type U is always monitored.

500 Hz speed monitoring

When an effective 500 Hz magnet is driven over, a continuous path-dependent speed monitoring (V ü1 ) is triggered for the next 250 meters . Again, the switching speed (V after undershooting to ) the restrictive speed monitoring (V u2 ) switched. For train types M and U, this is set to a constant 10 km / h. This restrictive 500 Hz speed monitoring is also activated in the event of a 500 Hz influence while a restrictive 1000 Hz speed monitoring is already running (transfer of the restriction).

Key data of the various speed monitoring curves on the 500 Hz magnet:

train type
normal speed
monitoring V ü1
restrictive speed
monitoring V ü2
Switching speed V to
O from 65 to 45 km / h
in 153 m
from 45 to 25 km / h
in 153 m
from 30 to 10 km / h
at 153 m
M. from 50 to 35 km / h
in 153 m
constant 25 km / h constant 10 km / h
U from 40 to 25 km / h
at 153 m
constant 25 km / h constant 10 km / h

2000 Hz emergency braking

As before, the 2000 Hz track magnet at the main signal locations immediately triggers an emergency brake when the signal indicates a stop. This means that trains that have passed the main signal are brought to a standstill within the slip path .

A command issued by the dispatcher , a shunting run (with signal Sh 1 ), a substitute signal ( Zs 1 ), a caution signal ( Zs 7) or an opposite-track substitute signal (Zs 8) can cause the driver to drive past the main signal showing the stop. He then has to press the command button, a toggle button or a push button, which prevents emergency braking. The maximum speed is limited to 40 km / h during key operation after 2000 Hz influence, and a continuous signal tone or voice output as a request to cancel the key operation is heard. The command button must be held down while the 2000 Hz magnet is being passed.

After passing the 2000 Hz magnet with the command button pressed, the "Command 40" indicator lights up. The operation of the command button has no effect at a speed of more than 40 km / h.

The operation of the command key is the recording device recorded. The operational regulations for train journeys with a special order must be observed.

Free button to reduce operational disabilities

After the driver has covered 700 meters since a 1000 Hz influence, he can free himself from speed monitoring by pressing the free button. This prevents operational hindrances if the signal has switched to travel in the meantime. Exemption is permitted if the driver has undoubtedly perceived a travel concept greater than 30 km / h and if no 500 Hz or 1000 Hz influence is to be expected within 550 m. The monitoring function becomes ineffective here, but continues to run in the background for the remaining distance. If there is another 1000 Hz influence in this area, the monitoring function becomes effective again; if there is a 500 Hz influence after an impermissible release, automatic braking is initiated regardless of the speed. The driver can no longer escape from 500 Hz monitoring with the release button, since the emergency braking on the 2000 Hz magnet would take place too late. The possibility of exemption and the speed monitoring which continues to run concealed up to 1250 meters after a 1000 Hz influence were already introduced with the PZ 80 type. If another 1000 Hz influence occurs within this 1250 meters, or the remainder up to the end of the period after liberation, the speed of the respective type of train indicated by the indicator light is immediately monitored.

Restrictive mode

The introduction of the restrictive mode in the vehicle unit was a major innovation of the PZB 90 compared to the previous versions. After a falling below the switching speed (V order ) is applied to the restrictive speed monitoring (V u2 switched). This is to ensure that a train which, after a stop, drives against a main signal showing a stop and accelerates, comes to a stop within the slip path.

The restrictive mode is indicated in the driver's cab by alternating flashing of the indicator lights 70 and 85 .

The driver can also free himself from speed monitoring in restrictive mode with the free button if no 500 Hz influence is active. He is only allowed to do this if he has unequivocally recognized a travel concept> 30 km / h and no further influence is to be expected within the next 550 m. Otherwise, the same rules apply as for exemption from a non-restrictive 1000 Hz influence: A further 1000 Hz influence monitors compliance with the speed indicated by the indicator light (instead of the restrictive 45 km / h, to avoid operational restrictions), a further 500 Hz influence leads to immediate emergency braking. In order not to impair operation too much, the stopping place at the platforms is placed with a stop board (Ne 5) either in front of a 500 Hz magnet or at the end of the monitoring route - i.e. just before the 2000 Hz magnet at the main signal.

Monitoring the maximum speed of the train

The maximum speed of the train, which has to be entered in the train data under "VMZ", is monitored independently of the speed monitoring that is triggered by the track magnets. The maximum speed of the motor vehicle can never be exceeded.

The maximum permissible speed of a signal-guided train with effective punctual train control is 160 km / h in Germany in accordance with Section 40 (2) of the Railway Construction and Operating Regulations (EBO).

The maximum monitored speed, depending on the type of train, is at most:

  • for the train type O 165 km / h
  • for train type M 125 km / h
  • for the train type U 105 km / h

If the PZB is not effective, the permissible maximum speed in Germany has been limited to 50 km / h since the end of 2012 in accordance with Section 40 (2) EBO; before that, the limit was 100 km / h. If the PZB is switched off by means of a fault switch, the speed of new PZB in-vehicle equipment is therefore monitored at 50 km / h, and for old ones at 100 km / h.


This monitoring function was developed for starting or turning train journeys. The start program prevents the speed from exceeding 45 km / h for a defined distance. When the travel direction switch is moved to the "V" position, on some vehicles already in the "M" position, the start program is activated, which corresponds to the 1000 Hz monitoring function with the distance covered for the clearance and thus runs 550 m long.

Up to version 1.6 it was possible to reset the on-board unit by briefly moving the direction switch to the "R" position, and thus to free yourself from restrictive monitoring functions without authorization. This has been fixed in version 2.0.

Registration function

The electronic recorder constantly records data such as the driving speed, the distance covered, the condition of the main air line (filled / vented), any influences, operation of the PZB buttons and collective fault messages, but also the registration number of the railroad vehicle driver , the respective direction of travel, train numbers and the type of braking entered and braking hundredths of the resulting operating mode (O, M, U) on a data storage cartridge (DSK). The data storage cassettes are designed as ring buffers and store the data compressed up to 30,000 km and approximately the last 50 to 90 km of the distance covered in detailed form in the so-called short-distance memory. After accidents or other dangerous events, the data storage cassette with the registered data is secured and the short-path memory is evaluated.

There are two types of data storage cartridges. The DSK10 introduced with the I60R contains its own microcontroller and saves the data with a battery backup. When DSK20 that vehicles with MVB is used, however, there is an actual disc a simple PCMCIA - Flash card .


Austrian main signal (above) and distant signal below . The flexible distant signal distances in Austria do not fit well with the PZB 90 operating program.
ETCS vehicle computer (
European Vital Computer ). The PZB can be integrated into the ETCS on- board unit via an STM .

Because of the punctiform transmission of the signal information, the trackside equipment of the PZB is not technically secure because it works according to the open- circuit principle. Failures of the track equipment can only be determined through special tests. Nevertheless, the PZB is very reliable because the track equipment is made up of purely passive components that do not require a power supply. The control system is in the form of signals from contacts of wings and wheel power closers and light signals from controlled by the signal group Interfacing relay , which are hardly prone to failure because of the no-load switching. Much of the detail is designed in such a way that errors work on the safe side.

The operating regulations in Austria only partially match the operating program of the PZB 90. The flexible braking distances customary at ÖBB are not coordinated with the monitoring of the braking curve. The continuous braking distance monitoring of the PZB 90 requires uniform distant signal distances, as they are especially common in the network of the former Deutsche Bundesbahn. A nationwide replacement of the PZB by the successor system ETCS will take a long time for financial reasons. (see also: Indusi: Austria )

Further development

Errors in the PZB 90 have been corrected with software version 2.0. Until then, it was possible to cancel the restrictive 500 Hz test without authorization by moving the direction switch to the reverse position and then forwards again . Previously, if a traction vehicle came to a stop so that the PZB vehicle magnet was exactly above the track magnet, it was only possible to continue driving by engaging the fault switch.

Recently, many lines operated in train control have been upgraded to technically supported train control with PZB , as it is now possible to install controlled 2000 Hz magnets without coupling to a main signal. These track magnets are switched ineffective remotely by train conductors or work independently .

The cross-border use of many locomotives requires the installation of several train control systems. One tries to keep the costs for this under control with generic train control computers. If a vehicle is equipped with an ETCS computer, a Specific Transmission Module (STM) is used on routes without ETCS equipment to receive, process and forward the information transmitted by the national route equipment to the vehicle computer.

The vehicles steering committee of the Federal Railway Authority decided in August 2014, in connection with the EBO amendment of July 25, 2012, that in the case of future vehicle registrations, technical monitoring in disruptive operation to a maximum speed of 50 km / h (instead of the previous 100 km / h) is to be considered.

With regard to ETCS, PZB 90 is managed as a class B system .

Special variants

AVG mode

The Albtal-Verkehrs-Gesellschaft developed its own variant of the PZB 90 for vehicles with good braking power to speed up operations. The pull type O is permanently set in this. Deviating from the PZB-90 standard,  the speed is only limited to 65 km / h at a stop ( <10 km / h for at least 15 s) within 500 m after a 1000 Hz influence. The indicator lights 70 and 85 flash at the same time, which is referred to as “common-mode flashing”, and an exemption is then only possible after 800 m from the influence. In addition, this AVG mode is not transferred as restrictive mode in the event of a subsequent 500 Hz influence. This variant of the PZB was also adopted by the RegioTram Kassel .

Version AKN

On the AKN routes , trains without appropriate equipment must run in the lower train type, at least in braking position P and at a maximum of 60 km / h.


When it became mandatory to equip vehicles with PZB 90, DB Schenker Rail (now DB Cargo ) decided to convert the I60, which is still based on relay technology , to the 36x series so that safety comparable to that of the PZB 90 is achieved. After a 1000 Hz influence, a braking curve runs that reaches 25 km / h after 45 seconds. After a 500 Hz influence, monitoring is carried out at 10 km / h, but in the case of a 2000 Hz influence when the command button is pressed, only 60 km / h is monitored. With this design, the fault switch can also be activated while driving without emergency braking.

S-Bahn Hamburg

Due to the short distance from the distant signal, a PZB variant is used on the Hamburg S-Bahn , which monitors for lower speeds and in some cases dispenses with the restrictive mode. This variant is an access requirement on the routes of the S-Bahn Hamburg, which is why vehicles traveling on other routes must have a switching device. Vehicles for mixed operation either have an additional row of blue indicator lights, or the LM 70 and 85 light up at the same time instead of the LM 65.

After a 1000 Hz influence, the speed must fall below 65 km / h after 18 seconds in connection with a distance of 300 m. After 200 m there is the possibility of exemption (LM 1000 Hz goes out), unless a 500 Hz influence has occurred in the meantime. The state after the LM has gone out also serves as the start of the start program. In the event of a 500 Hz influence, the speed must be reduced from 50 to a maximum of 42 km / h within 80 m. If there is a 500 Hz influence within 90 m after departure, the restrictive mode takes effect, in which 20 km / h is monitored. A restrictive mode with 1000 Hz influence does not exist in this variant.

500 Hz magnets are only installed here if the protective distance behind a signal indicating stop would not be sufficient for 2000 Hz emergency braking from full or local maximum speed; at a distance from the relevant protection point that corresponds to both the rapid braking distance from the 500 Hz magnet and the rapid braking distance for at least 45 km / h (42 km / h in particularly cramped conditions) from the 2000 Hz track magnet.

Type HGK

For the network of ports and goods traffic in Cologne there is the variant "PZB90 - type HGK -" because of the regular braking distance of 400 m. Here, 2.5 s after a 1000 Hz influence, a 24 s long linear braking curve from 60 to 30 km / h begins. An exemption is possible after 400 m, the monitoring ends automatically as with the DB-PZB after 1250 m. When the command button is pressed, the HGK-PZB can reach speeds of up to 45 km / h. The vehicles have a manual switchover device and an additional indicator light "30" for this purpose.

With other PZB types, only a maximum speed of 40 km / h is permitted on the HGK network.


In trams, too, coupling coils acting at points are used to influence trains. Because of the high braking performance of the vehicles approved in accordance with the tram construction and operating regulations, they are often only used here as driving blocks for main and important driving signals. They are slightly smaller than the magnets commonly used on German railways and are usually arranged to the left of the left or right rail.

Tyne & Wear Metro

The light rail Tyne & Wear Metro in north-east England has been using a simplified version of the PZB since it started operating in 1977. The way the magnets are laid is different, however; they are installed on the inside of the rail on the left in the direction of travel. Only 2000 Hz magnets are used for emergency braking when driving over main signals indicating stop. The vehicles are equipped with magnetic rail brakes and can therefore be braked from a maximum speed of 80 km / h to a standstill within a slip distance of 150 m. The signaling principle is the same as with the time-controlled, mechanically acting travel locks ("Tripcock") of the London Underground, but with the advantage of contactless, inductive transmission.

At special danger spots such as stump tracks in front of the tunnel ends, several switchable 2000 Hz magnets are laid one behind the other at ever shorter intervals down to about 10 meters. The last magnet before the end of the tunnel is always effective. The entry of the trains is controlled via a series of rail contacts, which are operated by the wheel flange of the leading axle of the train, as well as by these switched time relays. If a train adheres to the braking curve, the magnets become ineffective immediately before it passes. But if the train is too fast, it will run over one of the 2000 Hz magnets before it is short-circuited. This triggers the emergency braking. This prevents the train from colliding with the end of the tunnel (see also the Moorgate underground accident ).


See also

Web links

Commons : Punctual train control  - collection of pictures, videos and audio files

References and comments

  1. Jürgen Janicki, Horst Reinhard: Rail Vehicle Technology . Bahn Verlag, 2008, ISBN 978-3-9808002-5-9 , p. 257 ff.
  2. Infrastructure status and development report 2019. (PDF) Performance and financing agreement II. In: eba.bund.de. Deutsche Bahn, April 2020, p. 124 , accessed on May 17, 2020 .
  3. Lothar Fendrich (Ed.): Manual Railway Infrastructure. Springer, Berlin / Heidelberg 2007, ISBN 978-3-540-29581-5 , p. 641.
  4. Lutz Brauweiler: PZB 90 from the point of view of interoperability . In: signal + wire . 92, No. 12, 2000, ISSN  0037-4997 , p. 29.
  5. Point train control (PZB), Indusi. Retrieved January 24, 2018 .
  6. German Bundestag (ed.): Answer of the Federal Government to the minor question from the MPs Stephan Kühn, Dr. Anton Hofreiter, Winfried Hermann, other MPs and the Alliance 90 / THE GREENS parliamentary group (...): Equipping the Deutsche Bahn AG route network with train control systems (PDF; 131 kB). Printed matter 17/4966 from March 1, 2011.
  7. Peter Thomas: How safe is the German rail network? . FAZ.net , August 6, 2013.
  8. The equipment with 500 Hz magnets, however, started before the changeover to the PZB 90 and was gradually continued.
  9. 500 Hz magnets are mostly missing in Austria (see also: Indusi: Austria ).
  10. Because the 2000 Hz magnet is not rendered ineffective by Sh 1 on the main signal showing the stop, the command key must be used to move over it (but not with pure blocking signals).
  11. Ril 483.0101 Section 4 Paragraph 7 c) Sentence 3
  12. If a train is standing at the stopping board - e.g. B. at a train crossing on a single-track line - the restrictive mode is active if the previous signal showed a signal aspect containing "expect stop" to signal the stop. One consequence was that 500 Hz magnets only remain activated when driving at speeds of less than 40 km / h. In contrast to the past, in order to avoid an unnecessarily restrained driving style, passages should also be signaled if the trains in question have to keep to traffic stops.
  13. Technical monitoring of the maximum speed in PZB malfunctioning in vehicle equipment with PZB 90 functionality. (No longer available online.) Federal Railway Authority, August 20, 2014, archived from the original on October 29, 2016 ; accessed on October 28, 2016 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.eba.bund.de
  14. Jürgen Janicki, Horst Reinhard: Rail Vehicle Technology . Bahn Verlag, 2008, ISBN 978-3-9808002-5-9 , p. 262.
  15. Since the flash memory is assumed to have a limited lifespan, the memory cards are replaced after a certain number of erase cycles.
  16. This includes the connection from the signal to the track magnet. Broken cable cores or a lack of contact lead to automatic braking.
  17. ^ A b Peter Schmied: Train control at the ÖBB . In: Swiss Railway Review . No. 4, Minirex-Verlag , Lucerne, 2000.
  18. As a result, however, the PZB was unable to develop its intended effect.
  19. Technical monitoring of the maximum speed in PZB malfunctioning in vehicle equipment with PZB 90 functionality ( memento of the original from February 9, 2016 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. . Technical announcement 20/2014 of August 20, 2014. @1@ 2Template: Webachiv / IABot / www.eba.bund.de
  20. a b c d Steffen Benesch: Application rules for the document "Protocol on the implementation of operational test cases of PZB functions in the context of confirmation runs - PZB 90 AVG -" (DB document no. 14-34-006-EB-PZB) . Issue B0-F, April 26, 2016 (PDF; 403.8 KiB)
  21. Ril 301.0101A03 Section 2
  22. Steffen Benesch: Application rules for the document "Protocol on the implementation of operational test cases of PZB functions in the context of confirmation runs - PZB 90 S-Bahn Hamburg -" (DB document no. 14-34-005-EB-PZB). Issue B0-F, April 26, 2016 (PDF; 513 KiB)
  23. a b c Guideline 819 “Planning LST Systems”. Module 819.20 "Design of the safety systems of the DC-operated S-Bahn Berlin and Hamburg"
  24. a b Extract from the collection of operational regulations (SbV) of the railway infrastructure company (EIU) of Häfen und Güterverkehr Köln AG. F. Additional provisions to PZB 90 for the HGK area. (Pages 18-20)
  25. Extract from the collection of operational regulations (SbV) of the railway infrastructure company (EIU) of the ports and goods traffic Cologne AG. D. Supplementary provisions to Ril 408.01-09, to 408.0651 Section 2 (page 12)