What kinds of signalling and train working systems are in use in India? The block sections may be handled manually or automatically, or by some combination of those. Some sections still use different forms of physical token systems such as the Neale's Ball Token instruments. Other than the block system some other special- purpose methods of train working are used in some circumstances. There are many old and new kinds of signalling systems used by IR. Many regions use lower- quadrant or upper- quadrant semaphore signalling (now with electric lamps for night operation, but formerly using oil lamps). Many routes have been fitted with (automatic or manual, 2- , 3- or 4- aspect) colour- light signal systems that are electrically operated. Apart from these FAQ pages, some extracts of the IR General Rules on train working are also available. AWS (Automatic Warning System) is an in- cab signal warning system, is used in suburban EMU systems, primarily Mumbai. It was proposed for main lines including New Delhi - Agra, Howrah - Mughalsarai, etc. However, early trials on the Howrah - Mughalsarai stretch did not succeed as the track- side magnets and other equipment were subject to theft and vandalism. Busy urban areas have electronic interconnections among the signal systems of the stations within the areas. Suburban systems generally have colour- light signalling and automatic block systems, sometimes with AWS or some form of automatic train stop systems (ATP, automatic train protection) as well. Automatic train stop systems were tried on some main lines in the 1. A Train Management System (TMS), from Bombardier, is used on the Mumbai suburban system (Churchgate - Virar) which provides centralized online monitoring of train positions. The Delhi Metro system uses Continuous ATC (CATC) including ATS and ATP on all its sections. Its metro (underground) section uses a flavour of ATO. Drivers are still on board each train on the underground section, but under normal conditions they don't do much beyond handling the door opening and closing. All normal operations of running the trains - - accelerating them, braking them, etc., are handled by the ATO system, with speeds up to 8. The ATO system was supplied by Alstom (France). Around Chennai, several suburban stations have their signals automatically controllable from Basin Bridge using a fault- tolerant system that interconnects the signalling of up to 3. This system also provides for 6 voice channels for communication among these stations. This system was developed indigenously by SR, the Dept. Many points exist which have to be manually operated at the location of the points after using a key to unlock the points. Following British practice, IR's signalling is essentially route signalling where the signals generally indicate which route has been set for a train, letting the driver choose the speed as appropriate for the divergences, curves, etc. Of course no modern system of signalling is purely route- based or speed- based, and there are elements of speed signalling in some of IR's signalling as well. To give a sense of the variety of systems in use, here is a sample . What is 'isolation'? Isolation refers to methods of protecting one line from the adjacent lines, e. A train or any rolling stock that is stopped on one of the lines while another train is moving through on the adjacent line should be prevented from moving and running over the points to the main line or fouling the adjacent line. There are several methods adopted to ensure isolation. Haye's Derails (which guide the flanges of wheels over and across to the outer side of the rails to derail a moving vehicle), Scotch Blocks (which prevent points from being set for vehicles on the loop line to be sent to the main line), and similar devices are sometimes used (more so in the past - these are less common now). Indian Railway Level Crossing Gates Filetype Pdf To ExcelMore commonly now, derailing switches (points that deliberately take the moving vehicle off the line and derail them) or points that lead to sand humps or sidings are used. Derailing switches or points to sand humps, sidings, etc., can also be interlocked (see below) so that they are automatically set to isolate the line when signals are taken off for the adjacent line. In addition, sometimes these switches have sensors so that unintended movement over them automatically bring signals on all adjacent lines back to danger. Q. What's the 'clearing point' or 'fouling point' or 'fouling mark'? The clearing point is the point ahead of a stop signal up to which the track must be kept clear of obstructions in order for a train to be accepted from the rear of the signal. In most cases this is with reference to home or outer home signals guarding entrance to station limits from a block section. The distance from the stop signal to the clearing point is the overlap (also overrun, or clearing distance). The overlap is usually about 4. MACL signalling where warners or distants protect the approach to the stop signal. No trains may be parked to the rear of the clearing point on the track protected by the stop signal. This provides a margin of safety in case a train overshoots a stop signal which is on, because of brake failure, driver inattention, etc. The fouling point or fouling mark is a point to the rear of a converging junction, such that a train must be to the rear of that point in order to ensure that any train moving on the other converging line can proceed without being obstructed. Stop signals guarding convergences are usually placed some distance to the rear of the fouling point for the junction; this distance is also known as the overlap, and again, provides a margin of safety against trains overshooting the stop signal. A similar safety distance is maintained ahead of the last stop signal of a station, before pulling off signals for a departing train; this is usually 1. Fouling points are usually marked by a stone or cement slab with 'FP' written on it by the side of the tracks. The fouling point may also be marked for a siding to indicate that a rake must be stopped beyond it in order to avoid obstructing other trains passing by on the through tracks or on to other sidings. A number on it indicates the number of standard coaches or wagons that may be safely stabled on that siding. Q. What are the last- vehicle indications that IR uses? The last vehicle of a train is supposed to carry a red lamp at the rear. Earlier, the requirement was for merely an oil lamp, which was often missing or very feeble. In recent years provision of an electric lamp has become more common (it is mandated in the rules). Level crossings: a guide for managers, designers. The authorisation of railway. South Africa is located at the southern tip of Africa. It is bordered by Namibia, Botswana, Zimbabwe, Mozambique, Swaziland and Lesotho. It is a vast country with. Axle counting systems with inductive wheel sensors have established themselves with many railway. Future Challenges to Axle Counting Systems. Indian Railway Level Crossing Gates Filetype Pdf MergeAn Automatic Integral Safety System for Railways. Solving Problem Of Unmanned Level Crossing). Indian Railway and other railways. Opening and closing of gates at a railway level crossing. In general, level crossing gates are operated. The major challenge faced by the Indian railway. CHAPTER IX LEVEL CROSSING AND GATEMAN. General Location : As far as possible. New BuILD CAR PARk GuIDeLInes foR CAR PARk DesIGneRs, oPeRAtoRs AnD owneRs 3 1. Last vehicle indications are of different types. A large 'X' is often seen painted on the rear of the coach that is the last one. A set of concentric circles may also be seen, although this seems to be going out of use now. EMU/DMU rakes have a smaller painted 'X' (red on white) at the rear, or sometimes a series of diagonal strokes painted on. The information is also provided to the section controllers. In some cases when working entirely within one block section, an 'LV' sign is not needed, if the number of coaches or wagons is communicated telephonically to the next station. Q. What's 'interlocking'? In order to ensure that the signalling system never provides unsafe (conflicting) signals and the points are not set for more than one train that might end up proceeding on to the same section of track and hence suffering a collision, various schemes have been developed to coordinate the settings of the points and the signals within the region controlled by a signalbox or signal cabin. Mechanically operated interlocking. The most prevalent systems today . The wires that operate signals, and the rods that control points, are all interconnected in the lever frames at the signal cabins so that they are literally 'interlocked' - - the position of one lever or key physically obstructs the movements of other levers and keys which control points or signals that can be set in conflicting ways. Manually operated interlocking. This is a form of mechanical interlocking as well, but relies on the signalman to move about from one set of points and signals to another carrying with him the keys used to operate them. At small stations and on less busy branch lines various forms of manually operated mechanical interlocking are still . At points controlling catch sidings in hilly areas, often the interlocking is manual where the driver has to use a key provided by the stationmaster or signalman of the last station before the siding - - the key is inserted into the interlock box which notifies the signal cabin and the points are then set for the main line and the signal is pulled off, giving the train authority to proceed. Depending on the state of the block instrument and the interlocking set up for the local layout of lines, these instruments would dispense a key only when the appropriate combination of signals had been set; the key would then be used to unlock points to divert a train on to a loop, for instance - - and while the points were so set, that key would not be released and the signals could not be changed. Hepper's Key Transmittters and other key interlocking systems (Annett's Key, etc.) allowed for operating interlocked ground frames and points outside the range of direct mechanically connected operation. A common system in use was Sequential Key Interlocking, which saved on the installation of point rodding and instead relied on the signalman walking over with a key to lock or unlock points. As an example, consider a station with a main line and a loop line. To receive a train on the main line, a key is inserted into the signal frame in the cabin or platform, which allows the Outer and Home signals of the station to be pulled off. In order to receive a train on the loop line instead, the key is used as before to pull off the Outer signal, but the Home is kept at danger. Instead, when the train has stopped at the Home signal the key is removed and taken to the facing points for the loop.
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