Automatische treinbeïnvloeding
Encyclopedia
Automatische TreinBeïnvloeding or ATB is a Dutch
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 train protection system developed in the 1950s. Its installation was spurred by the Harmelen train disaster
Harmelen train disaster
The Harmelen train disaster was the worst railway accident in the history of the Netherlands. Harmelen, in the central Netherlands, is the location of a railway junction where a branch to Amsterdam leaves the Rotterdam to Utrecht line...

 of 1962.

ATB operates by the train collecting electrical signals from line-side apparatus which will override the driver's controls in the following situations:
  • a) failure to brake for a red signal
    Railway signal
    A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal's indication and acts accordingly...

     (ATB makes an immediate brake application)
  • b) failure to reduce speed at a caution signal (ATB will slow the train sufficiently to stop at the next signal).
  • c) failure to observe speed limit (ATB slows the train) (such as around a sharp curve or low speed turnout
    Railroad switch
    A railroad switch, turnout or [set of] points is a mechanical installation enabling railway trains to be guided from one track to another at a railway junction....

    )


For completeness, the ATB should also:
  • d) restrict the speed of the train after passing a signal at danger
    Signal passed at danger
    A Signal passed at danger , in British railway terminology, occurs when a train passes a stop signal without authority to do so. It is a term primarily used within the British Railway Industry, although it can be applied worldwide.-Categories of SPAD:...

    . This was a factor in the Glenbrook train disaster
    Glenbrook train disaster
    The Glenbrook rail accident occurred on 2 December 1999 at 8:22 am in New South Wales, Australia, in which seven passengers were killed and 51 passengers were transported to hospital with injuries. The accident occurred when an interurban train collided with the rear wagon of the Indian Pacific...

    .


Speed limits are set in 5 steps: 40 km/h, 60 km/h, 80 km/h, 130 km/h and so-called volle materiaalsnelheid (i.e. full speed allowed for that type of train), which can be 140 km/h at most for non-high speed trains. If the train's maximum allowed speed is lower, the 130 km/h setting is omitted.

Design Limitations

One of the early system's design limitations is the inability to intervene at speeds below 40 km/h. Several accidents at train station
Train station
A train station, also called a railroad station or railway station and often shortened to just station,"Station" is commonly understood to mean "train station" unless otherwise qualified. This is evident from dictionary entries e.g...

s and railroad yards occurred because the driver failed to stop at a red signal
Signal passed at danger
A Signal passed at danger , in British railway terminology, occurs when a train passes a stop signal without authority to do so. It is a term primarily used within the British Railway Industry, although it can be applied worldwide.-Categories of SPAD:...

 and ATB didn't intervene, because the speed was below 40 km/h. Another problem is the maximum speed set to 140 km/h. Though there are tracks with a design speed of up to 160 km/h, they cannot be used up to full speed because ATB Eerste Generatie or ATB-EG (First Generation, early system) doesn't allow this.

Enhancements

To overcome the design flaws, a second generation ATB (ATB Nieuwe Generatie or ATB-NG = ATB New Generation) has been developed which more or less overcomes the aforementioned problems. The speed is now set in 10 km/h intervals from 0 through 200 km/h and the amount of braking is relative to the weight of the train. Though (or maybe because) the early and new systems are totally different and completely incompatible from the design point of view (though a train equipped with ATB-NG also has an ATB-EG system on-board, so the system has backward compatibility
Backward compatibility
In the context of telecommunications and computing, a device or technology is said to be backward or downward compatible if it can work with input generated by an older device...

), they do not interfere with each other: they both can safely be installed at the same track. Also, there are enhancements to the early system, called ATB-Plus (lifts the 140 km/h maximum system speed) and ATB-Plus-Plus (designed to further reduce Stop Tonend Sein or STS-passages = Signals Passed At Danger).

Another problem with ATB is the patent held by ACEC-Alstom
Alstom
Alstom is a large multinational conglomerate which holds interests in the power generation and transport markets. According to the company website, in the years 2010-2011 Alstom had annual sales of over €20.9 billion, and employed more than 85,000 people in 70 countries. Alstom's headquarters are...

, which doesn't allow other manufacturers to supply the system and offers poor interoperability
Interoperability
Interoperability is a property referring to the ability of diverse systems and organizations to work together . The term is often used in a technical systems engineering sense, or alternatively in a broad sense, taking into account social, political, and organizational factors that impact system to...

 with other systems. This is one of the reasons the recently constructed Betuweroute
Betuweroute
The Betuweroute is a double track freight railway from Rotterdam to Germany. Betuweroute is the official name, after the Betuwe area through which it passes, but the line is popularly referred to as Betuwelijn, after an older track in the same region. The Germans have named their part the...

 uses the European standard European Railway Traffic Management System (ERTMS).

See also

  • Pulse Code Cab Signaling
    Pulse code cab signaling
    Pulse code cab signaling is a form of cab signaling developed in the United States by the Union Switch and Signal corporation for the Pennsylvania Railroad in the 1920s...

  • Train stop
    Train stop
    Part of a railway signalling system, a train stop or trip stop is a train protection device that automatically stops a train if it attempts to pass a signal when the signal aspect and operating rules prohibit such movement, or if it attempts to pass at an excessive speed.- Basic operation :The...

     – protects against a)
  • Automatic Warning System
    Automatic Warning System
    The Automatic Warning System is a form of limited cab signalling and train protection system introduced in 1956 in the United Kingdom to help train drivers observe and obey signals. It was based on a 1930 system developed by Alfred Ernest Hudd and marketed as the "Strowger-Hudd" system...

     – protects against b)
  • Automatic Train Protection
    Automatic Train Protection
    Automatic Train Protection in Great Britain refers to either of two implementations of a train protection system installed in some trains in order to help prevent collisions through a driver's failure to observe a signal or speed restriction...

    – protects against c)
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