For any station whether a wayside or a junction, the Engineering department prepares a plan depicting all the lines, points, Level Crossings if any, Foot-over Bridge (FOB), Sub-way if any coming within the station section, Bridges if any, gradient etc. This plan is called as the “P-way Plan”. This plan is studied by the Signal Engineers and based on this a Signalling Plan is prepared indicating the following:

* All gradients within the station limit on either side up to 2.5 Kms.
* Kilometer and class of level crossing gate within the station limits, whether interlocked or not.
* Up & Dn direction, Name of the important junction and immediate station on either side.
* Location of signals, with reference to the point and level crossing gate.
* Marking of signals, points, and level crossing gates.

* Inter signal distances and distance between warning boards & signals
* Type of Block working with adjacent station and location of Block instrument.
* Type of turnouts.
* Description of siding.
* Restriction on dead end sidings.
* Crank handle details.

* Details of Axle counters / Track circuits.
* Signalling Over lap.
* Holding capacity of all running lines and sidings.
* Note regarding telephone communication provided between ASM and Level
* crossing with in and out of station section.
* Reference to approved engineering plan on which the signalling plan is based.
* CRS‟s dispensation for deviation from G&SR / SEM, if any.
* Aspect sequence chart for CLS.

* Name of the station, Standard of station.
* Class of station, Centre line with kilometers, North point.
* Names of the stations with distance on either end of the station.
* Panel position / SM‟s control, with spare knobs / slides.
* Detection table.

A typical signaling plan can be seen. All signals and points are given a number, as per certain standard conventions.
First the civil Engineers who lay the track structure on the ground prepare a plan called permanent way plan or Engineering scale plan. Based on this plan signaling plan is made by signal engineers for catering to the train operation requirements. One of the unique features of Railways working is the level crossing gate where a road and the rail track cross each other at the same level.

The level crossing gates are of following types.
1. Manned and interlocked with signals.
2. Manned and not interlocked with signals.
3. Unmanned Level crossing.

When the standards of Interlocking are discussed. Interlocking of level crossings with signal will also be covered. If the interlocked gate is within the station limits, the station signals will protect the movement of trains over the gate. If the interlocked gate is in the block section, independent signals will be provided on either side of the gate and will be controlled by the Railway. Staff manning the gate.

lines|points|Level Crossings|how to make Railway Signalling Plan|Aspect sequence|Chart|CLS|Bridges|gradient|Foot-over Bridge (FOB)|Indian Railway Signalling Plan

GK/RT0032 – Provision of Lineside signals

This document defines the mandatory requirements for the provision of lineside signals and the sequences in which signal aspects shall be presented to train drivers, in respect of plain line, diverging junctions and for bi-directional lines, to enable them to

1. a) stop safely at a signal at danger
2. b) regulate train speed to negotiate junctions safely
3. c) regulate train speed to that of an immediately preceding train

Signal Designation: The terms “passable and non passable” apply for operating purposes, and “Automatic/Controlled” for signal control system purpose.

Automatic:  A signal which does not require specific action by a signaller or automatic route setting equipment in   order to show a proceed aspect.

Controlled: A signal that requires a specific action by a signaller or automatic route setting equipment on   each occasion that it is required to show a proceed aspect (other than when a signal is arranged to   work automatically)

Railway Signalling layout of signal positioning

Required reading time:

  It is the sum of

1. a) the time that is necessary for a driver approaching a signal to achieve the following.

  1) identify the signal that is applicable to the driver.

  2) observe the information presented by the signal.

  3) interpret the information to determine what action, if any, is required.

1. b) such additional reading time as is reasonably practicable to provide.

  Required reading time is specific to each individual signal and is not applicable where all trains start from rest.

Signal spacing:  The distance between the signal or lineside sign displaying the first cautionary aspect and the signal or lineside sign at which the train is required to stop.

Stop Signal:  The word “signal” includes not only colour light and semaphore signals, but also any lineside sign that performs that function of a signal. for the purpose of lineside signals, the term stop signals also include shunting signals, stop boards, buffer stops and point set indicators.

Choice of signal type:

Running line: A stop signal that controls a running direction movement along or onto a running line shall be a main signal except shunting signal provided for the control of other than time tabled passenger train movements. It is permissible for such a shunting signal to become facing for running movements (operated as a preset shunt).

Sidings: A stop signal controlling movements into or along sidings shall be a shunting signal, unless other considerations require it to be a position light aspect on a main signal.

Block signalling: In all forms of fixed block working, the entrance and exit of every signal section shall be denoted by a stop signal.

Facing junctions: A stop signal shall be provided on every line on which signalled movements can approach facing points, with the exception of train operated points equipped with points indicators.

Level Crossings: Where a level crossing to be protected by interlocked signals, a stop signal shall be provided on every line on which signalled movements approach the crossing

Conflicting movements: A stop signal shall be provided on every line on which signalled movements can approach an area of conflict.

Lockout Systems: Where a lockout system for the protection of trackside personnel is provided, a stop signal shall be provided on every line on which signalled movements can approach the area protected by the lockout system, positioned so as to protect the personnel making use of the system.

Signals at point of reversal:

  Where trains are required to reverse on lines worked by track circuit block or absolute block, a stop signal (set back signal) shall be provided at the point of reversal to authorise the movement in the reverse direction.

  Where practicable, the setback signal shall be positioned so that

1. a) the whole of the train comes to a stand behind the signal after making the outward movement.
2. b) when the outward movement has been completed, the distance between the end of the train and the siganl is minimised.

Ground Frames: Signals on running lines protecting ground frame points shall be controlled signals, designated non-passable. It is permissible for movements from running lines into entirely within sidings accessed by ground frame operated points to be controlled by hand signal.

Constraints on the positioning of stop signals

1. Position of signals relative to facing points:

  Where a signal reads over facing points, it shall be positioned not more than 800m from the first set of facing points, so that risk due to the following is minimised.

1. a) the likelihood of the driver forgetting the indicated route
2. b) the ability to accelerate to greater than the permissible speed over the diverging route.

  The 800m limit does not apply to:

1. a) points operated from Ground frame
2. b) facing points which are out of use
3. c) facing points which are in same position for movements from the signal
4. d) a signal which is positioned parrallel with other signals and one of parallel signal within 800m of facing points.
5. Position of signals relative to points & level crossing

  Where stop signals shall be positioned so that,

1. a) the associated overlap is clear of points, level         
2. b) trains stopped at the signal do not stand over points or level crossings or foul any other         

  Stop signals shall be positioned so that trains stopped at them do not stand over runaway catch points.

Constraints on positioning of stop signals

3. Position of signals relative to platforms:

  Stop signals shall be positioned to minimise the risk arising from passenger trains without central door locking or power operated doors stopping with a platform adjacent to only part of the train.

4. Position of signals relative to the hazardous location:
5. a) Where practicable, stop signals shall be positioned to avoid the risk of a passenger train stopping in a hazardous locations (eg: on a viaduct, or on a tunnel)

Where a signal is required in such a location, i.e to maintain headway, signalling controls shall be applied to the previous signal so as to minimise the risk of a train being brought to a stand at such location.

  It is not necessary to apply such special controls whrere risks are adequately controlled by other means such as:

1. b) Where practicable, stop signals shall be positioned such that the driver not exposed to hazards such as live c. traction rails when   leaving the cab of a train stopped at signal.
2. c) Stop signals shall be positioned so that the exposure of the driver to hazard whilst using the signal post telephone is minimized.
3. d) On lines electrified with overhead systems, stop signals shall be appropriately positioned in relation to a neutral section or section gap.

Bi-directional signalling

1. a) For every signal provided, there shall be a   parallel signal for movements in the same   direction on the adjacent lines. Refer GK/RT8037   for positioning of other signals.
2. b) On bi-directional lines where a predominant   (normal) direction of traffic is designated, it is   permissible for signalling in the contra-flow   direction to be three aspect. whilst that in the   same (normal) direction on the adjacent line is   four aspect, provided that a lower permissible   speed is applied for contra flow direction  

Identity of signals Signal numbering:

  Each signal shall have an identity that is unique to its controlling signal box or locality, comprising the signal box prefix code, the signal number and where required, a suffix. The number of each signal worked by a lever shall be the same as the lever number

  All signals , including automatic and distant signals, except distant signals worked from the same lever as a stop signal, shall be individually numbered as part of sequence. Separate sequence shall be used for running signals and shunting signals.

Signal numbering:

  Except where signals are worked by levers, the rules for determining the sequence of numbers are as follows:

1. a) The sequence of numbers shall be separate and distinct   from other numbered functions such as points, ground

  frame releases etc.

1. b) The sequences shall be logical and rational and shall be  
2. c) Odd numbers shall be used for down direction signals and   even numbers for up direction signals.
3. d) Odd numbers shall usually ascend and even numbers   descend in the direction of traffic flow.
4. e) If there is more than one running line in each direction, the   numbers for each line shall be in separate sequences.

Signal numbering:

1. f) As far as possible train drivers shall be presented   at successive signals with signal numbers which   are consecutive odd or even numbers.
2. g) Where up to five signals applying to traffic in the     same direction are positioned side by side the last   digit of each signal identity shall be different.
3. h) Where more than five signals are positioned side   by side, the last digit of the identities of adjacent   signals shall be different

The following signal suffixes shall be used for the applications indicated:

  BR-   for banner repeating signal, the number being the same as that of repeated signal

  CA-   for co-acting signal, the number being the same as that of primary signal

  R-   solely for a distant signal worked form the same operating device as a stop signal, the number being the same as that of stop signal

  RR-  solely for an outer distant signal worked form the same operating device as a stop signal same as that of stop signal

Block Signal

• A Stop signal that controls the entrance to or signifies the termination of a block or signal section (and any other stop signal)
  within station limits.

Signal Section

• In a track circuit block area, the line between two consecutive block signals (whether or not these are within the area of control of the same signal box) in the same direction of travel.

Non-block Signal

• A mid-section stop signal specifically provided for the protection of a level crossing or other hazard and without block or signal section controls.

Overlap

• The distance ahead of a stop signal up to which the line must be clear, and where necessary locked, before the signal in the rear can clear.

Track Circuit

• A Portion of the railway line having fixed boundaries and providing information on its state of occupancy to the signaling system. This traditional name does not preclude alternative forms of train detection.

APPLICATION OF TRACK CIRCUIT BLOCK

1. Maybe Employed on both uni-directional and bi-directional lines.
2. Level of traffic and types of vehicles to be suitable for reliable operation.
3. Integrity level to be sufficient for the application.
4. Not necessary for the signaller to directly observe trains.
5. No restriction on the location of signal boxes.
6. Block signals may be automatic, semi-automatic, or controlled.
7. Controlled signals may work automatically on selection.

Following Facilities may also be used :

1. Mechanically operated Controlled signals and distant signals.
2. Permissive and shunt working
3. Automatic stepping up of warning facilities.
4. Train-operated route release i.e. automatic route release.
5. Automatic route setting.
6. Automatic working of distant signals and/or aspects.
7. Fixed distant signals and (reflectorized) distant boards.

PRINCIPLES OF OPERATION

1. Signals for all normal train movements.
2. Signals at the point of reversal for reverse movement.
3. Only one train in a signal section at any time except where permissive or shunt working allowed.
4. Promotion of correct sequence of events.
5. Block signal without a separate overlap track circuit not to prove its own overlap clear provided the overlap is proved clear in the procedural aspects of the block signal in the rear.
6. Where there are automatic or semi-automatic signals for both directions, opposing signals shall clear for one direction only at anyone time.
7. The Clear direction selected by the operation of the controlled signals, or by the operation of direction or acceptance controls if there is more than one signaller.

SYSTEM REQUIREMENTS 

Train Detection

1. Indications to the signallers – the presence or absence of trains in each signal section.
2. Track Circuit indications to correspond to the actual controls applied to signals, especially where overlaps at automatic signals are part of the rear section.
3. Appropriate indications of approaching and conflicting trains.

Bi-directional Control

1. Maybe co-operative if there is more than one signaller or overall control by a single signaller by additional switches or levers.
2. Directional control for un-limited number of trains or restricted to a single train.
3. Direction Controls to be suitably indicated to all associated signallers.

Signal Controls

1. Signal section and the overlap at the exit signal to be clear.
2. Automatic replacement of signal aspects, where practicable.
   
3. Except for mechanical signals, signal sticks for all controlled block signals.
4. Signal Sticks overridden by the selection of automatic working.
5. If no automatic replacement of aspect, the replacement to be proved before clearance of block signal in rear. This replacement proving shall be lever or control plus aspects.

Replacement by lever only if –

1. The signal is mechanically operated, and
2. An arm repeater is not provided, and
3. The signal does not give entry to a bi-directional Line worked by any non-token system, and
4. The block signal in the rear controlled from the same signal box and
5. The block signal in the rear cannot work automatically.

Semaphore signals

1. Semaphore stop signals at either end of a signal section or semaphore distant signals that apply to these stop signals –
2. the overlap controls to be suitable for fog conditions.

(GK /RT 0078)

Communication between Signal Boxes

• Emergency alarm facility and voice communication.

Stop signal communication

1 . Signal Post Telephone.

Identification of Signal

• Signal identification plates
  (GK / RT 0009)

Permissive and shunt working

• Where authorized, under the authority of a position light signal, semaphore subsidiary signal, or a semaphore shunting signal.

Switching out of signal boxes

1. Controls to be transferred to another signal box including the ability to replace each or all block signals.
2. Transfer of all indications and communications.

LEVEL CROSSINGS

1. Maybe block or non-block signals
2. Block signal to be a controlled signal by the gate-operator
3. Or a semi-automatic signal

System Failure

• Any failure not to result in the clearance of the signals. (Failures to be on the safe side)

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Definition of Station

1. A railway station or a railroad station and often shortened to just station, is a railway facility where trains regularly stop to load or unload passengers and/or freight.

Purpose of Railway station

For exchange of passengers and goods.
1. For control of train movements
2. To enable the trains on a single line track to cross from opposite directions.
3. To enable the following express trains to overtake
4. For taking diesel or coal and water for locomotives
5. For detaching engines and running staff

6. For detaching or attaching of compartments and wagons
7. For sorting of bogies to form new trains, housing of locomotive in loco sheds.
8. In emergencies in ease of dislocation of track due to rains, accidents etc…
9. For repairing engines and changing their direction
10. Railway station are having suitable approach roads from surrounding areas.

Types of Stations

1. Wayside Stations, Junction Stations, Terminal Stations

Wayside Stations

1. In this type arrangements are made for crossing or for overtaking trains. Wayside stations are of the following types.
i.Halt stations ii.Flag Stations iii.Crossing stations.

Halt Stations

1. A halt, is a small station, usually un staffed and with few or no facilities. In some cases, trains stop only on request, when passengers on the platform indicate that they wish to board, or passengers on the train inform the crew that they wish to alight.

Flag Stations

1. Flag stations describes a stopping point at which trains stop only on an as-need or request basis; that is, only if there are passengers to be picked up or dropped off.
2. These stations have no overtaking or crossing facilities and arrangements to control the movement of trains. These stations have buildings, staff and telegraph facilities.

3. Some of the flag stations have sidings also in the form of loops.

Crossing Stations

1. Provided with facilities for crossing
2. In this type at least one loop line is provided to allow another train if one track is already occupied by a waiting train
3. Generally the train to be stopped is taken on the loop line and the through train is allowed to pass on the main line

Junction stations

1. At a junction stations, lines from three or more directions meet
2. The stations where a branch line meets the main line are known as junctions.Arrangements in junction stations
3. Facilities for interchange of traffic between main and branch line
4. Facilities to clean and repair the compartments of the trains
5. Facilities for good sidings, engine sheds, turn table etc.

Terminal Stations

1. It is a station where a railway line or one of its branches terminates
2. Facilities required in terminal stations
3. Watering, coaling, cleaning, servicing the engine

4. Turn table for the change of direction of the engine
5. Facilities for dealing goods traffic. Such as marshaling yard, engine sheds, sidings etc.
6. In circulating area, ticket office, restaurant etc are provided and it is directly connected to the road

Terminal Stations

Classification of Stations

Stations can be classified on the basis of their operation as

1. Block stations-Class A, Class B and Class C
2. Non Block Stations-Class D stations or Flag stations
3. Special class stations.

Block Stations

The stations at the end the block sections are called Block stations Authority to proceed is given in the shape of token at these stations.

Class A Station: On these stations the track is cleared up to 400m beyond the home signal for giving permission to approach a train
Class B Station: In such stations, the other signal is provided at about 580m from the home signal
Class C Station: On these stations passengers are not booked. It is simply a block meant for splitting a long block section and to reduce the interval between the successive trains.

Non Block Stations

1. Also known as Class D station or Flag station
2. Situated between two consecutive block stations
3. May not be telegraphically connected to the adjacent stations

4. No equipment or staff is provided for controlling the movements of the trains.
5. Trains are stopped by flag signals only

Special class stations

Stations not coming under block station and non block stations are called special class station

Platforms – Passenger and Goods platforms

1. A railway platform is a section of pathway, alongside rail tracks at a railway station, metro station or tram stop, at which passengers may board or alight from trains or trams.
2. Almost all rail stations have some form of platform, with larger stations having multiple platforms.
3. Platform types include the bay platform, side platform (also called through platform), split platform and the island platform.

4. A bay platform is one at which the track terminates, i.e. a dead-end or siding.
5. A side platform is the more usual type, alongside tracks where the train arrives from one end and leaves towards the other.
6. An island platform has through platforms on both sides; it may be indented on one or both ends, with bay platforms.

Passenger Platform

Goods Platform

Definition of Yard

1. An area consisting of a network of railway tracks, sidings, and sheds for storing, maintaining, and joining engines and carriages.
2. A yard is defined as a system of tracks laid within definite limits for various purposes such as receiving sorting and dispatch of vehicles.

Railway Yard

Types of Yards

1. Passenger yards, Goods yards, Marshalling yards, Locomotive yards

Passenger yards

1. Function of passenger yard is to provide all the facilities for the safe movement of passengers.

Facilities in passenger yards
1. Booking office, enquiry office, luggage booking room, cloak room and waiting room for passengers
2. Parking space for vehicles
3. Signals for reception and dispatch of trains

4. Platforms and sidings for shunting facilities
5. Facilities for changing batteries
6. Facilities for passing a through train
7. Washing lines, sick lines facilities

Passenger yards

Goods yards

1. A goods station (also known as a goods yard, goods depot or freight station) is, in the widest sense, a railway station which is exclusively or predominantly where goods (or freight) of any description are loaded or unloaded from ships or road vehicles and/or where goods wagons are transferred to local sidings.
2. These are provided for receiving, loading and unloading of goods

Requirements of a goods yard

1. Approach road for movement of goods
2. Sufficient number of platforms for loading and unloading
3. Sufficient number of godowns

4. Booking office
5. Cart weighing machine
6. Cranes for loading and unloading
7. Vacuum testing machine

Marshalling yards

1. Marshalling yard is a railroad yard found at some freight train stations, used to separate railroad cars on to one of several tracks.
2. It is the place where goods wagons received from different centres are sorted out and placed in order to detached at different stations.

3. The marshalling yards are distribution centres.
4. Empty wagons are also kept in marshalling yards.

Factors for the efficient functioning of marshalling yards

1. Shunting operations should not disturb the regular trains
2. Should be kept parallel to the running trains
3. Movement of wagons in one direction only
4. Repair facilities should be provided on one or more sidings
5. Connected to all important railway stations
6. Goods yard should be nearer to the marshalling yard

Types of marshalling yards

(i)Flat yard (ii)Gravity yard (iii)Hump yard

Flat yard

1. Flat yards are constructed on flat ground, or on a gentle slope. Freight vehicles are pushed by a locomotive and coast to their required location.
2. A flat yard has no hump, and relies on locomotives for all car movements

Gravity yard

1. The whole yard is set up on a continuous falling gradient and there is less use of shunting engines.
2. Typical locations of gravity yards are places where it was difficult to build a hump yard due to the topography.
3. Gravity yards also have a very large capacity but they need more staff than hump yards and thus they are the most uneconomical classification yards.

Hump-yard

1. These are the largest and most effective classification yards, with the largest shunting capacity—often several thousand cars a day.
2. The heart of these yards is the hump: a lead track on a hill (hump) that an engine pushes the cars over.
3. Single cars, or some coupled cars in a block, are uncoupled just before or at the crest of the hump, and roll by gravity onto their destination tracks.
4. A hump yard has a constructed hill, over which freight cars are shoved by yard locomotives, and then gravity is used to propel the cars to various sorting tracks.

Locomotive yards

1. This is the yard which houses the locomotives for various facilities such as watering, fueling, cleaning, repairing, servicing etc.

Requirements of a locomotive yard

1. Should be located near the passenger and goods yards
2. Water column
3. Engine shed, Ash pit, inspection pit, repair shed, turn table

4. Hydraulic jack for lifting operations
5. Over head tank and loco well
6. Sick siding
7. Place for future expansion

Level crossings

1. A level crossing (a primarily British term; usually known as a railroad crossing in the United States) is an intersection where a railway line crosses a road or path at the same level
2. Other names include railway crossing, grade crossing, road through railroad, and train crossing.

3. The type of facilities provided at level crossing depends up on the following
4. Nature of the road
5. Nature of the traffic on road
6. Number of trains passing over the level crossing

Classification of level crossing

1. Special class – Traffic is exceptionally heavy
2. A class – On grand trunk roads
3. B class – Metelled roads
4. C class – unmetelled roads
5. D class – used for cattle‘s as ramps and pedestrians only

Station Equipments

1. For efficient running of trains, safety of traffic, repairing, cleaning, examining of locomotives etc. some equipment and machinery is needed. These equipment’s are known as station equipment

Engine sheds

1. Railway engine sheds were provided at terminal stations, junctions, and other locations around the railway.
2. They provided covered accommodation for servicing locomotives – this could be simple tasks such as changing brake blocks to more complex task that involved dismantling and repairing the engine.
3. Types of engine sheds are (i) Rectangular type (ii) Circular type

Rectangular type engine shed

1. In this type of engine shed, two parallel tracks are laid, which meet at one or both the ends.
2. The engine can come from one end and leave the shed in other end
3. They need more space; they are widely used in India