This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Signalling block system" – news · newspapers · books · scholar · JSTOR(July 2007) (Learn how and when to remove this message)
A block instrument on the Midland Railway
Signalling block systems enable the safe and efficient operation of railways by preventing collisions between trains. The basic principle is that a track is broken up into a series of sections or "blocks". Only one train may occupy a block at a time,[1] and the blocks are sized to allow a train to stop within them.[2] That ensures that a train always has time to stop before getting dangerously close to another train on the same line. The block system is referred to in the UK as the method of working, in the US as the method of operation, and in Australia as safeworking.
In most situations, a system of signals is used to control the passage of trains between the blocks. When a train enters a block, signals at both ends change to indicate that the block is occupied, typically using red lamps or indicator flags. When a train first enters a block, the rear of the same train has not yet left the previous block, so both blocks are marked as occupied. That ensures there is slightly less than one block length on either end of the train that is marked as occupied, so any other train approaching that section will have enough room to stop in time, even if the first train has stopped dead on the tracks. The previously-occupied block will only be marked unoccupied when the end of the train has entirely left it, leaving the entire block clear.
Block systems have the disadvantage that they limit the number of trains on a particular route to something fewer than the number of blocks. Since the route has a fixed length, increasing the number of trains requires the creation of more blocks, which means the blocks are shorter and trains have to operate at lower speeds in order to stop safely.[a] As a result, the number and size of blocks are closely related to the overall route capacity, and cannot be changed easily because expensive alterations to the signals along the line would be required.
Block systems are used to control trains between stations and yards, but not normally within the yards, where some other method is used. Any block system is defined by its associated physical equipment and by the application of a relevant set of rules. Some systems involve the use of signals while others do not. Some systems are specifically designed for single track railways, on which there is a danger of both head-on and rear-end collision, as opposed to double track, on which the main danger is rear-end collisions.
^Hinson 2020, The Block System: 1: Basic Principles.
^Kichenside & Williams 2008, pp. 73–88.
Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).
and 28 Related for: Signalling block system information
Signallingblocksystems enable the safe and efficient operation of railways by preventing collisions between trains. The basic principle is that a track...
Railway signalling (BE), or railroad signaling (AE), is a system used to control the movement of railway traffic. Trains move on fixed rails, making them...
Automatic blocksignaling (ABS), spelled automatic blocksignalling or called track circuit block (TCB) in the UK, is a railroad communications system that...
In railway signalling, a moving block is a signallingblocksystem where the blocks are defined in real time by computers as safe zones around each train...
transport system, signalling control is the process by which control is exercised over train movements by way of railway signals and blocksystems to ensure...
The modern-day system mostly uses two, three, and four aspect colour-light signals using track circuit – or axle counter – blocksignalling. It is a development...
generation Shinkansen signalling developed by Japan National Railways (JNR). In Europe and elsewhere in the world, cab signalling standards were developed...
railways outside of Europe. ETCS is the signalling and control component of the European Rail Traffic Management System (ERTMS). ETCS consists of 2 major parts:...
Mechanical signalling in all States followed British practice using route signalling with slight differences between States. The basic running signal was the...
variants Signallingblocksystem, a way of controlling train movement Block (musician) (Jamie Block), an anti-folk musician based in New York, US Block letters...
Electronic Token Block is a system of railway signalling used in the United Kingdom. It is a development of the physical token system for controlling traffic...
one pair for each block in each direction. Wigwag is a form of flag signalling using a single flag. Unlike most forms of flag signalling, which are used...
The railway blocksignalling bell code is a system of bell sounds used in Great Britain to communicate between manually operated Signal Boxes in implementing...
by Dr. William Robinson. The Hall Signal Company installed the disc signals as part of automatic blocksignalsystems, initially utilizing line wire circuits...
diagonal for restricting indications. Speed signalling is indicated not by additional signal heads, but by a system of white or amber "orbital" lights placed...
Railway signals in Germany are regulated by the Eisenbahn-Signalordnung (ESO, railway signalling rules). There are several signallingsystems in use,...
indicate that the signal operates automatically (as in automatic blocksignallingsystems) and in many cases indicates that the signal is 'permissive',...
(ATP) system. The French word balise is used to distinguish these beacons from other kinds of beacons. Balises are used in the KVB signallingsystem installed...
Trackside signalling is not mandatory and can be replaced with cab signalling using DMI. It is considered to be a "quasi-moving-block" system. This is...
The signallingsystem used on the rail transport in Norway is regulated by the Regulations of December 4, 2001 no. 1336 about signals and signs on the...
signalling. Signalling in the UK uses route signalling. Most railway systems around the world, however, use speed signalling. Under route signalling,...
divested the signalling technology to Alcatel-Lucent. In April 2006, Thales Group announced it would be acquiring Alcatel Rail Signalling Solutions in...
train control systems, minimizing the chances of trains colliding with each other. This was built around the signallingblocksystem with signal boxes along...
form of blocksignalling, which does not permit two trains to be within the same section of track (block) at the same time. Blocksignalling decreases...
train protection systems that continually check that the speed of a train is compatible with the permitted speed allowed by signalling, including automatic...
Global Information
