Search results
Results from the WOW.Com Content Network
Like the manual block systems outlined above, automatic systems divide the route into fixed blocks. At the end of each block, a set of signals is installed, along with a track-side sensor. When a train passes the sensor, the signals are triggered to display the "block occupied" aspect on the signals at either end of that block.
This was called the "absolute block system". Fixed mechanical signals began to replace hand signals from the 1830s. These were originally worked locally, but it later became normal practice to operate all the signals on a particular block with levers grouped together in a signal box.
The safety distance (safe-braking distance) between trains in fixed block and moving block signalling systems. From the signalling system perspective, the first figure shows the total occupancy of the leading train by including the whole blocks which the train is located on.
The safety distance (safe-braking distance) between trains in fixed block and moving block signalling systems. In railway signalling, a moving block is a signalling block system where the blocks are defined in real time by computers as safe zones around each train. This requires both knowledge of the exact location and speed of all trains at ...
The Toronto subway uses a variety of signalling systems on its lines, consisting of a combination of fixed block signalling and moving block signalling technologies.. The oldest signalling system is known as automatic block signalling and was designed for the system's heavy rail lines: Line 1 Yonge–University, Line 2 Bloor–Danforth and Line 4 Sheppard.
Some railroads, notably the Pennsylvania Railroad (PRR), had a system of manual block signals activated by wayside operators in stations or interlocking towers eliminating the need for some trains to stop. [8] This manual block system is still on use on the Long Island Rail Road, which had been a subsidiary of the PRR.
The ATS system at the Control Center is not a vital system and serves only to automate the routing of trains based on the overall timetable. The location of the train is also used to inform passengers of arrival times. The MTA's form of CBTC uses a reduced form of the old fixed-block signaling system, requiring that both be maintained at high cost.
Signalling systems used to control the movement of traffic may be either of fixed block or moving block variety. Fixed block signalling. Most blocks are 'fixed' blocks, i.e. they delineate a section of track between two defined points. On timetable, train order, and token-based systems, blocks usually start and end at selected stations. On ...