Railway Signalling Concepts https://www.railwaysignallingconcepts.in Information About Axle Counter,Track Structure Point & Crossing,Cable Schematics,CBTC Equipment,Overlaps,Core Plans,Earthing,ERTMS,Headway Calculation,Hot Axle Box Detectors,Interface Design,Level Crossing,Markers & boards,Bonding Plan Electrical Lockings,Route locking,Automatic Warning Systems AWS,Point Circuit,Equipment Treadle,Track Layout,Track Circuit Interrupters,Train Protection Warning System (TPWS),Slip Siding & Catch Siding. Thu, 28 Jan 2021 08:20:48 +0000 en-US hourly 1 https://wordpress.org/?v=5.4.2 Indian Railways Signalling Slip Siding & Catch Siding https://www.railwaysignallingconcepts.in/indian-railways-signalling-slip-siding-catch-siding/ https://www.railwaysignallingconcepts.in/indian-railways-signalling-slip-siding-catch-siding/#comments Thu, 28 Jan 2021 06:16:36 +0000 http://www.railwaysignallingconcepts.in/?p=73 catch siding in railways, the definition of ghat section in Indian railways, slip-sliding in railways, sand hump in Indian railways, IRDSO, iriset, types of railway signals, points and crossings in railways pdf, station working rules Indian railways, signal overlap in railways, sand hump in Indian railways, slip-sliding in railways, slip routes in Indian railways Railways […]

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catch siding in railways, the definition of ghat section in Indian railways, slip-sliding in railways, sand hump in Indian railways, IRDSO, iriset, types of railway signals, points and crossings in railways pdf, station working rules Indian railways, signal overlap in railways, sand hump in Indian railways, slip-sliding in railways, slip routes in Indian railways

Railways Signalling Slip Siding & Catch Siding

Railways Signalling Slip Siding & Catch Siding:- On Indian Railways, for all gauges, the maximum gradient permitted is 1:400, where as1:1200 is usually allowed within the station yard. No station yard should be steeper than 1:260, except due to geographic conditions. Where such gradient cannot be avoided within the station yard, condonation of CRS is to be obtained for providing SLIP SIDING. Slip siding will prevent vehicles from entering the block section.

Slip Siding

Where gradients are steeper than 1:80 falling towards the station, to prevent vehicles entering station section from block section. This arrangements is know as „CATCH SIDING‟ Catch siding will prevent vehicles entry into block section.

Catch Siding

Slip sidings and „Catch sidings‟ points must be interlocked with block instruments and
these sidings should not be used for shunting or stabling purposes.

Railways Signalling Slip Siding | Catch Siding

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Train divided Metro Train https://www.railwaysignallingconcepts.in/train-divided-metro-train/ https://www.railwaysignallingconcepts.in/train-divided-metro-train/#comments Wed, 02 Dec 2020 01:49:09 +0000 http://www.railwaysignallingconcepts.in/?p=690 Train divided Metro Train Train divided –(1) If a train is stopped by an irrevocable emergency brake application and cab signaling indications are normal, the Train Operator shall examine the Train Control Monitoring System panel, or Train Integrated Management System panel, as the name given, to ascertain the cause, if indication of faults in multiple […]

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Train divided Metro Train

Train divided –(1) If a train is stopped by an irrevocable emergency brake application and cab signaling indications are normal, the Train Operator shall examine the Train Control Monitoring System panel, or Train Integrated Management System panel, as the name given, to ascertain the cause, if indication of faults in multiple circuits affecting the whole train or rear cars of the train are present, the train shall not be moved until, it has been verified that the train is complete and coupled.

(2) After the verification about complete arrival and the integrity of the train is completed under sub rule (1), the Traffic Controller may authorise the Train Operator to make appropriate isolations and proceed. If the train is not divided, but is still unable to move on its own, the train shall be worked in accordance with sub rule (1) of rule 50.

(3) If the train is found to have parted , the Train Operator shall first satisfy himself that no passenger has been injured or has fallen from the train, and then –
(i) the passengers shall be cleared of the open ends of the train and train re-coupled with the help of assisting staff as per special instructions, if possible, in consultation with Traffic Controller and Rolling Stock Supervisor.

(ii) if the Train Operator has successfully re-coupled the train, he shall return to the leading cab, report the circumstances to the Traffic Controller and seek permission to proceed to the next station following the instructions given by the Traffic Controller.

(4) The train shall be withdrawn from passenger service at the next station and worked to depot for investigation of the incident.

(5) If train cannot be re-coupled, the Train Operator shall inform the Traffic Controller and the Traffic Controller shall then inform the Station Controller at the previous station to detrain passengers from the following train if possible, and use it to go to the site and take at least two staff with him.

(6) The Train Operator of the following train shall drive his train in Coded Manual Mode as far as the signaling permits, thereafter the Traffic Controller shall instruct the Train Operator to drive the train under Restricted Manual Mode and proceed at reduced speed as near to the divided train as possible and stop, and the Station Controller and the staff shall then leave the train from the front, or from the side, as applicable, and board the parted train.

(7) The staff shall be positioned at the rear of the front portion of the train and the Train Operator of the divided train shall return to the leading cab, make the necessary isolation and seek permission from the Traffic Controller to proceed.

(8) The Traffic Controller shall instruct the Train Operator to proceed at a speed not exceeding ten kilometer per hour as far as the next station and to stop at the far end of the platform.

(9) The other staff shall be positioned at the front end of the rear divided train portion and the assisting Station Controller shall, then, drive the rear portion of the train from the shunting position of the assisting train with utmost caution, and with the staff keeping a look out at the front, maintaining continuous communication with the traffic controller and the train shall be driven to the next station at a speed not exceeding ten kilometer per hour in any case.

(10) On arrival of the train at the station, passengers shall be detrained.

(11) The two portions of the train shall then be worked under the supervision of rolling stock Engineer in Restricted Manual M ode, if possible to the nearest depot or siding at a slow speed.

(12) The assisting train shall proceed once the cab signaling displays a proceed code and shall entrain passengers at the next station and resume normal working.

(13) In case of depot being in the direction opposite to the direction of working of the divided train, the rear portion of the divided train shall first be worked toward the nearest station in the direction of depot after positioning a security staff at the divided train portion in the rear, after the Train Operator has changed his cab in the leading direction of movement, in consultation with the Traffic Controller.

(14) The other parted portion of the train shall then be worked cautiously in the shunting mode after appropriate isolation, at a very slow speed after positioning the other security staff at the divided end keeping a close look out at the front and maintaining continuous communication with the Traffic Controller.

(15) After reaching the station, the assisting train can resume normal operation.

(16) The parted portions of the divided train shall be worked to depot under supervision of rolling stock supervisor in Restricted Manual mode, if possible.

(17) In case it is not possible to move any parted portion of the divided train on its own power, it shall be worked to the depot using another suitable train under instructions of the Traffic Controller. 

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Railway Single Section Digital Axle Counter CEL DACF 710 A & DACF 710 P https://www.railwaysignallingconcepts.in/railway-single-section-digital-axle-counter-cel-dacf-710-a-dacf-710-p/ https://www.railwaysignallingconcepts.in/railway-single-section-digital-axle-counter-cel-dacf-710-a-dacf-710-p/#comments Wed, 04 Nov 2020 03:36:26 +0000 http://www.railwaysignallingconcepts.in/?p=2706 Railway Single Section Digital Axle Counter CEL DACF 710 A & DACF 710 P The system comprises of track side counting units, installed at both ends near the detection points on the track. No separate evaluator is required. Two versions available (i) DACF 710 P (Phase reversal type) The DACF 710 P is not affected […]

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Railway Single Section Digital Axle Counter CEL DACF 710 A & DACF 710 P

The system comprises of track side counting units, installed at both ends near the detection points on the track. No separate evaluator is required. Two versions available

(i) DACF 710 P (Phase reversal type) The DACF 710 P is not affected by the push trolleys having 4 spoke and 8 spoke wheels; and rail dolly. Trolley suppression track circuit is not required. It counts the following push trolleys: (a) Push trolley with perforated wheel; (b) Dip lorry and (c) Motor trolley.

(ii) DACF 710 A (Amplitude Modulation type) The SSDAC remains unaffected with all types of insulated push trolleys but goes into disturbed state (ERROR condition) for non insulated trolleys. Trolley suppression track circuit is required.

Components of DACF
The CEL DACF system consists of following units

Axle detectors

1. Transmitter (TX) coils – 2Nos. fed with 21 kHz and 23 kHz carrier signals
2. Receiver (RX) coils – 2 Nos. to receive the transmitter signal The Rx signal is phase modulated with each train wheel passing over the detection point.

Trackside electronic unit (SSDAC)

The SSDAC unit comprises total 8 cards namely:
Card No.1 & 2 – Signal Conditioning Card
Card No.3 & 4 – Micro controller logic blocks (2 Micro controllers)
Card No. 5 – Event Logger Card
Card No. 6 – Modem Card
Card No. 7 – Relay Driver Card
Card No. 8 – Power Supply Module (DC-DC converter)

Vital relay box

The VR box consists of dual relay i.e VR & PR relay of Q style, 24V and 1000 ohm. It is provided in the trackside location box along with SSDAC unit.

 

Vital relay box

SM’s Reset Box
– 1 No. for common resetting (when used in station area/platform lines)
– 2 Nos. for independent resetting (when used in block sections)

The reset box consists of the following:
i. The LED indications
a. Section Clear – Green indication.
b. Section Occupied – Red indication.
c. Power ON – Yellow indication.
d. Preparatory Reset – Green indication.
e. Line Verification – Yellow indication.

SM’s Reset Box

ii. SM’s key actuator.
iii. Reset Push button (Red colour). Fig. 4.2: SM’s Reset Box
iv. Counter for recording the number of reset operations.
v. 20 X 2 LCD display with backlit.
vi. 4 keys keypad for setting the date and time operation.
vii. 9 pin D-sub connector on the motherboard of reset box, used for downloading the data for analysis purpose.

Surge Voltage Protection Device This Surge Voltage Protection Device is provided to protect the equipments from surge voltages. This device is to be installed at each location along with every SSDAC unit.

 Surge Voltage Protection Device

Installation of Tx and Rx coils after replacement of rail Marking and drilling holes on web of rail 3 holes of 14 mm dia.on the rail web 0-170-340 mm at 86 mm from top for 90R rail and 88 mm. from the top for 52 Kg/60Kg. rail.

 Fixing of Marking Jig

 Installation of Tx and Rx coils

LED indications on SSDAC unit

The LED indications are provided on the facial plate i.e. on front side of different modules of SSDAC viz. SCC cards, MLB Cards, Modem Card, Relay Driver, DC-DC Converter and Event Logger to indicate OK or Error condition. These are as follows:

 LED indications on SSDAC unit

 

 Front view of SSDAC unit

 

Event Logger

Maintenance
Recording of Signal levels :- For maintenance of Single Section Digital Axle Counter various parameters are to be checked periodically. The various signal input and output levels and its limits which are to be recorded and adjusted to correct levels wherever necessary are given in following tables:

24 V DC Supply (Battery)
Measure the DC 24 V input to the system with charger ON, charger OFF condition with all the units connected (i.e. on load) or using dummy load.

24 V DC Supply (Battery)

Oscillator Output (TX Coils)

Oscillator Output (TX Coils)

Receiver Coil Output
Measure the RX coil signal output with and without dummy wheel.

Receiver Coil Output

Dummy wheel

 Digital Axle Counter

 Phase Reversal type Digital Axle Counte

SCC Cards (Cards 1 & 2)

Measure the DC voltages at monitoring sockets of SCC cards 1 & 2 with respect to ground.

Front view of SCC 1 Card

 

Modem Output (Card 6)

Check and record the modem signal output of SSDAC during normal working condition of the system.

Modem Output (Card 6)
                                                     Modem Output (Card 6)

 

Relay Drive (Card 7)

Check and record Relay drive output to the Vital Relay with section clear and section occupied condition. (This may be checked across R1 & R2 of relay coil in vital relay box).

Relay Drive (Card 7)
                                                              Relay Drive (Card 7)

DC –DC Converter Card (Card 8)

Measure the DC –DC Converter output voltages with respect to respective ground for 24 V DC input fed to the SSDAC.

 Front view of DC-DC Converter

 

Maintenance Schedule (Monthly)

(i) Tx & Rx Coil Axle Detectors (At site)

1. Measure the TX coil (21 KHz & 23 KHz) signal levels and record them. These measurements are to be tallied with the previous readings. These should be within the specified limits and should not change more than 10%.
2. Measure the Rx coil (21 KHz & 23 KHz) signal levels and record them. These measurements are to be tallied with the previous readings. These should be within the specified limits and should not change more than 10%.
3. Check the M12 Bolts & Nuts of web mounted TX & Rx coil Axle detectors. All the nuts should be in tight condition.
4. Check and tighten the deflector plates if found loose.

(ii) SSDAC Unit (At site)

1. The 2.2V DC signal levels of card 1&2 of the SSDAC Counting Units are measured and
2. recorded. The level should be between 2.0 to 2.5V DC.
3. DC-DC converter output voltages should be measured and recorded. The outputs
4. measured should remain within the specified limits and match with the previous readings.

5. The modem card output should be measured and recorded. The reading should match
6. with the previous readings
7. Check the relay driver output and it should be >20 V DC. This reading is recorded.
8. Ensure that screws of modules are tight.

9. Ensure that MS circular connectors are tight.

Power Supply (Battery Room & Site)

1. The 24V DC power supply should be measured and recorded. The 24V DC should remain within specified limits.
2. Inspect the battery charger and check its charging current and ensure it is properly
3. charging the battery.
4. Any interference with power supply and connections of SSDACis likely to cause failure.
5. This should be done only after ensuring that no train is occupying or approaching the section.

Inspection of Reset Box (SM’ s room)

1. Monitor the reset box while the train is occupying the section. The occupied (red)
2. LED should be glowing.
3. When the train clears the section, the clear LED (green) glows.
4. The Reset to the system is controlled through the key actuator & Reset button of
5. reset box. This should not be disturbed.
6. The LCD displays all the information regarding the system. (Please refer Handbook on Troubleshooting of Digital Axle Counter Section IV)

General

1. Check all the cable connections on the CTboard of apparatus case at both locations.
2. Ensure that these are in tight condition.
3. Check the deflector plates of the Axle detectors are in normal position. If found loose this should be properly tightened.

Repair of Faulty Cards

1. Before declaring any card is faulty, the fault should be analysed and confirmed.
2. Repair of cards is a highly technical job and is not possible at site. Hence Railways
3. should not carry it out. The card should be sent to CEL for repair.

Resetting Procedure :- 4.9.1 In station area

Common resetting
The common resetting of both SSDAC units is to be carried out when used in station area for platform lines, yard lines etc. Last vehicle (LV) proving is used in conjunction with reset box if required. Resetting operation
1. Insert SM’s key, turn right and keep pressed.
2. Press Reset button for 2 seconds.

3. Release SM’s key and Reset Button.
4. Turn left, remove SM’s key and keep in safe custody.

With the above operation

1. 48 V DC from reset box is extended to SSDAC unit.
2. Reset command is generated in MLB1 and MLB2 cards (Cards 3 & 4).
3. The SSDAC units are reset and counts become zero.
4. The SSDAC units attain the preparatory reset state.

5. The PR & PPR relays pick up and Prep. Reset indication glows on the reset box.
6. The reset counter reading increments by 1 count.
7. After one pilot train is passed in the section the system becomes normal.
8. Vital Relay picks up.

Note: Reset command to Micro-controllers will not be generated if system is in clear/preparatory/occupied state. System can be resetted if it is in error state or out counts were registered after occupied state.

4.9.2 In Block Section  – Independent resetting
The independent resetting of SSDAC units at each station is to be carried out when used in Block Sections. Sometimes SM’s key and button contacts are extended to a remote location for resetting purpose.

Resetting operation

1. Insert SM’s key, turn right and keep pressed.
2. Press Reset button for 2 seconds.
3. Preparatory LED starts flashing.
4. Release SM’s key and Reset Button.
5. Turn left, remove SM’s key and keep in safe custody.

With the above operation

1. 48 V DC from reset box is extended to SSDAC unit.
2. Reset command is generated in MLB1 and MLB2 cards (Cards 3 & 4).
3. The SSDAC units are reset and counts become zero.
4. The SSDAC units attain the preparatory reset state.

5. The PR & PPR relays pick up and Prep. Reset indication glows on the reset box.
6. The reset counter reading increments by 1 count.
7. After one pilot train is passed in the section the system becomes normal.
8. Vital Relay picks up.

                              

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Railway Signalling Glossary of Signalling Terms  https://www.railwaysignallingconcepts.in/railway-signalling-glossary-of-signalling-terms/ https://www.railwaysignallingconcepts.in/railway-signalling-glossary-of-signalling-terms/#comments Sun, 01 Nov 2020 17:44:48 +0000 http://www.railwaysignallingconcepts.in/?p=352 Railway Signalling – Glossary of Signalling Terms  This standard defined the meaning of commonly used signaling terms to ensure that each term is clearly understood and always use to convey the same meaning. The glossary is arranged in alphabetic order. Examples:          TERM        DEFINITION ALPHANUMERIC  ROUTE INDICATOR A ROUTE INDICATOR […]

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Railway Signalling – Glossary of Signalling Terms 

This standard defined the meaning of commonly used signaling terms to ensure that each term is clearly understood and always use to convey the same meaning. The glossary is arranged in alphabetic order.

Examples:       

  TERM        DEFINITION
ALPHANUMERIC  ROUTE INDICATOR A ROUTE INDICATOR that conveys its  information by alphanumeric characters.
APPROACH LIGHTING The lighting of a SIGNAL only on the approach of a train.
ATP Abbreviated term for AUTOMATIC TRAIN PROTECTION.
BANNER REAPEATING SIGNAL A SIGNAL that provides the driver with preliminary information about whether a SIGNAL is ON or OFF.
CD Abbreviated term for CLOSE DOORS INDICATOR.
FLASHING DOUBLE YELLOW (ASPECT) Displayed by a COLOUR LIGHT SIGNAL, informs the driver to expect the next MAIN SIGNAL at FLASHING SINGLE YELLOW.
HEADWAY The shortest distance or time interval between Two following trains, so that the second train can run at its normal operating speed without being restricted by the SIGNAL ASPECTS.
LAST WHEEL REPLACEMENT A control applied to a SIGNAL which replaces it
to its most restrictive aspect only after the whole
train has passed the signal.
LOS Abbreviated term for LIMIT OF SHUNT   INDICATOR.
NX Abbreviated term for ENTRANCE – EXIT SYSTEM.
SPAD SIGNAL passed at DANGER.
SUPPRESSION (AWS)  Inhibition of the operation of AWS track equipment for movements to which it does not   apply.
TORR Abbreviated term for TRAIN OPERATED ROUTE RELEASE.
WARNING (ROUTE CLASS) A ROUTE from one MAIN SIGNAL to the next main signal where the full OVERLAP is not available or not required

 

IDENTIFICATION OF SIGNALLING AND RELATED EQUIPMENT

To define the principles for ensuring that items of signalling and related equipment are clearly and unambiguously identified.

OBJECTIVES

The objective of identifying signalling and related equipment is to ensure that

1. Confusion does not arise in verbal or written communication   when geographical location and equipment are the subject   of communication.

2. Events, incidents and operational engineering activities can   be accurately and concisely described.

RESPONSIBILITIES            

Network Rail, as infrastructure controller, shall ensure that a procedure is in place that ensures that allocated identities are documented.

 PLACE NAMES

Geographic Identity Each of the following features shall have a name.

1. Control Centre, Signal Box or Gate Box

2. Ground Frame or Ground Switch Panel.

3. Tunnel, Viaduct, Swing bridge etc.

LINES & SIDINGS

Each line and siding within or adjoining a signaled area, shall have an identity.

 

IDENTIFICATION

Each signal box or locality shall be assigned a code which is unique as far is reasonably practicable.

 

BLOCK SYSTEM

Manually controlled block system shall be named by appropriate reference to the line and/or the ends of the block section (e.g. AA-BB DM Block).

 

TRAIN DETECTION

Each track section shall have an identity. The identity shall generally be unique to the signal box or locality as applicable. Train detection equipment associated with track section shall be identified by the track section identity and where necessary suitable suffixes.

 

LINESIDE SIGNALS

Each signal shall have an identity that is unique to the signal box or locality as applicable. Signals worked by levers shall be identified by the lever number. The following signal suffixes shall be used and the meanings are exclusive.

1. BR for a banner repeating signal, the number being as for the   repeated signal.

2. CA for a co-acting signal, the number being as for the primary   signal.

3. R only for a distant signal worked from the same lever as a   stop signal, the number being the lever number.

 

SIGNAL IDENTIFICATION PLATES

Identification plates shall be provided as the following signals:

1. Colour light signals

2. Semaphore running signals.

3. Position light shunt and limit of shunt signals.

4. Banner repeater signals.

Identification plates are not generally required at other types of signal or board but the provision of adequate identification plates or label shall be considered.

 

OPERABLE LINESIDE INDICATORS          

Each operable indicator not forming part of a signal shall have an individual identity. Loading / unloading indicators shall be identified in the same manner as signals. Other types of operable indicator shall be identified by association with the relevant function namely:

1. RA indicator(s) with signal, or with platform where there is   no relevant signal.

2. OFF indicator(s) with signal

3. SPAD indicator with signal(s)

4 Points indicators with points.

 

POINTS

Each point end (as defined and including catch points and hand points) worked or detected by a signalling function, shall have an identity that is unique to the signal box or locality as applicable. Points worked by levers shall be identified by the lever number.

 

LOCKOUT SYSTEMS

Each lockout section shall have a numeric identity unique to the signal box.

STAFF WARNING SYSTEMS

Each staff warning system shall have a place name and associated locality code.

TRACK – BASED DATA TRANSMISSION EQUIPMENT 

All balises, loops and other track equipment used for data transmission between track and trains shall be uniquely idetified.

 

TRAIN – BASED SIGNALLING AND DATA TRANSMISSION  EQUIPMENT

Where it is necessary for the operation of the signalling system for train-mounted equipment to report the identity of the train or vehicle on which it is installed, the infrastructure controller shall consult with the train operators to determine the system of identification to be used and shall establish and maintain a system for the allocation and recording these identities.

 

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Metro Rail Restricted Manual Mode Cut Out Mode https://www.railwaysignallingconcepts.in/metro-rail-restricted-manual-mode-cut-out-mode/ https://www.railwaysignallingconcepts.in/metro-rail-restricted-manual-mode-cut-out-mode/#comments Sun, 01 Nov 2020 07:27:35 +0000 http://www.railwaysignallingconcepts.in/?p=700 Metro Rail Restricted Manual Mode, Cut Out Mode, Low Speed Cut Out Mode,Run on Sight Mode Metro Rail Restricted Manual Mode Cut Out Mode – (1) The Restricted Manual Mode is the default mode of operation and is automatically initiated, when the automatic train control train borne equipment is first powered and it remains in operation until sufficient […]

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Metro Rail Restricted Manual Mode, Cut Out Mode, Low Speed Cut Out Mode,Run on Sight Mode

Metro Rail Restricted Manual Mode Cut Out Mode – (1) The Restricted Manual Mode is the default mode of operation and is automatically initiated, when the automatic train control train borne equipment is first powered and it remains in operation until sufficient conditions have been met to allow for a transfer to Coded Manual Mode.

(2) The Restricted Manual Mode shall be used-
(a) to operate trains in depots.
(b) following an emergency brake application on main line, and absence of cab signals.

(c) for entry to and up to exit from the depot; and
(d) on instructions from Traffic Controller.

(3) In Restricted Manual Mode, the train speed shall be limited to a maximum of twenty five kilometer per hour enforced by on board Automatic Train Protection equipment.

(4) All platform screen doors, where provided, will have to be operated manually by the Train Operator from the local panel provided near the train cab at the platform.

(5) The Train doors on the correct side will also have to be operated manually by the Train Operator.

Cut Out Mode –(1) The “Cut Out” Mode, is intended for use in case of complete failure of train borne signaling and train control system and in such mode the train speed shall be restricted to twenty five kilometer per hour, unless special provision is made as under-

(i) Low Speed Cut Out Mode – this is the default mode of operation in Automatic Train Control Cut-out condition, in which the propulsion system would cut out traction of the train above twenty five kilometer per hour speed and the Train Operator shall manually drive the train in accordance with the line-side signals and shall monitor and limit the speed of the train if it exceeds twenty five kilometer per hour speed, by service brake or emergency brake application.

(ii) High Speed Cut Out Mode – this mode, where provided, shall be employed only under specific instructions from the Operations Control Center, in which the operation in Automatic Train Control Cut-Out condition the propulsion system would cut out traction of the train above forty kilometer per hour and. the Train Operator shall manually drive the train in accordance with the line-side signals and shall monitor and limit the speed of the train if it exceeds forty kilometer per hour, by service brake or emergency brake application.

(2) In Cut Out modes, the train shall be operated by the Train Operator in accordance with line side signals and o n Radio verbal instructions from the Traffic Controller.

(3) Running of trains on mainline in Cut Out Mode is permitted only under instructions of the Traffic Controller.

(4) All platform screen doors, where provided, shall have to be operated manually by the Train Operator from the local panel provided near the train cab at the platform.

(5) The train doors on the correct side shall also have to be operated manually by the Train Operator. 

Run on Sight Mode –In Run on Sight Mode, which only operates in the absence of Automatic Train Protection signals from the track, the train is driven manually on line of sight and the speed is limited by Automatic Train Protection system to a maximum of twenty five kilometer per hour. When Automatic Train Protection signals from track are received, this mode automatically changes to Coded Manual Mode.

 

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Railway Track Circuits https://www.railwaysignallingconcepts.in/railway-track-circuits/ https://www.railwaysignallingconcepts.in/railway-track-circuits/#respond Sun, 01 Nov 2020 03:02:29 +0000 http://www.railwaysignallingconcepts.in/?p=2729 Railway Track Circuits OUTLINE 1. Introduction 2. Components 3. Working 4. Do’s & Don’t 5. Other technology 6. Present era of technology 7. Conclusion INTRODUCTION 1. Track circuit is simple electrical device used to detect the Presence/Absence of train on the rails. 2. Track circuit is the one of the primary input for a signal […]

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Railway Track Circuits

OUTLINE
1. Introduction
2. Components
3. Working
4. Do’s & Don’t
5. Other technology
6. Present era of technology
7. Conclusion

INTRODUCTION
1. Track circuit is simple electrical device used to detect the Presence/Absence of train on the rails.
2. Track circuit is the one of the primary input for a signal interlocking plant.
3. The signal cannot be green while there is another train on track segment ahead.

Track Circuit

COMPONENTS
1. Battery.
2. Track Relay.
3. Adjustable resistance.
4. Insulated rail joints.

Battery
1. Gravity cells are used .

Relay
1. A relay is electrically operated switch.
2. The Relay switch connections are usually labelled common ,normally closed, normally open.

Relay

Adjustable Resistance
TRc – Track Lead Resistance at feed end
TRr – Track lead Resistance at Relay end
RT – Regulating Resistance
Rr – Rail Resistance (Rail joint Resistance)
RB – Ballast Resistance
TSR – Train Shunt Resistance

Insulated rail joints
1. Track circuit required insulated rail joint for isolating it the adjacent track circuit.

2. Nylon IRJ
3. Glued IRJ

Insulated rail joints

 

Track circuit bonding

Rail bond need to be provided on track circuit have point turnout them.

Track circuit bonding

Track circuit bonding

 

WORKING

1. The portion of the Track which is to be Track circuited, is first provided with wooden or RCC sleepers and then the rails are insulated from the rest of the Track by the provision of Insulated rail joints.
2. At one end of the Track circuit feed is connected and at other end track relay is connected.
3. When the track portion is not occupied by trains, the fed is available for track relay and the relay is in energized condition.

When a train occupies the track circuit portion, the axel & wheels shunt the track much of the circuit current is passed through the wheels due to less resistive path and very less current is available for track relay, which is not sufficient enough to pick up the relay.

Simplified DC Track Circuit

Simplified Interlocking Relay Application

 

DEAD SECTION

1. Those section of the track circuit in which occupation by a vehicle cannot be detected.
2. Curved track.
3. Cross.
4. Bridge .

Dead Section 1

 

Dead Section 1

 

DO’S & DON’T

1. Top up distilled water if the electrolyte level is low in batteries.
2. Change the relay which is due to for overhauling.
3. Replace the damaged and corroded bonding wires.
4. Do not Tilt the relay.

5. Do not Test the track circuit by shunting with a wire only.
6. Track circuit does not get shunted properly by vehicles.
7. Its working length is dependent on immunity of track relay.

OTHER TECHNOLOGY
1. AC Track circuit.
2. Audio Frequency Track circuit.
3. Axle Counter.

OTHER TECHNOLOGY

 

 

OTHER TECHNOLOGY 1

 

PRESENT ERA

1. Indian Railways is installing a state-of-art technology along train tracks to detect of faults and defective parts in coaches, wagons and locomotives.
2. The new system, which uses high-speed infrared and digital cameras, will replace physical examination of the wagons by railway staff.
3. The project, which will be run as trial project will be installed at 10 locations at an estimated cost of 73 crore rupees in the first phase.

CONCLUTION

1. DC Track circuit are the simplest , least costly and most reliable type of track circuit.
2. Now a days for signalling purposes , trains are monitored automatically by means of TRACK CIRCUIT.
3. Track circuit play important role in stop accidents,traffic .

 

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Metro Rail occurrences Flooding unsafe conditions https://www.railwaysignallingconcepts.in/metro-rail-occurrences-flooding-unsafe-conditions/ https://www.railwaysignallingconcepts.in/metro-rail-occurrences-flooding-unsafe-conditions/#respond Thu, 29 Oct 2020 08:29:28 +0000 http://www.railwaysignallingconcepts.in/?p=693 Metro Rail occurrences Flooding unsafe conditions Unusual occurrences – (1) All Metro Railway employees shall be conversant with the location and use of fire alarms and fire fighting equipment at their place of work. (2) All Metro Railway employees observing the smoke or fire shall raise the alarm by means of the equipment provided or […]

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Metro Rail occurrences Flooding unsafe conditions

Unusual occurrences – (1) All Metro Railway employees shall be conversant with the location and use of fire alarms and fire fighting equipment at their place of work.

(2) All Metro Railway employees observing the smoke or fire shall raise the alarm by means of the equipment provided or by informing the Station Controller and Traffic Controller as may be most appropriate and expeditious.

(3) If smoke or fire is reported on a train between stations, the Train Operator shall inform the Traffic Controller, drive his train to the next station and detrain passengers. Traction power shall then be switched off, and in overhead traction territory the pantographs of the affected train lowered, or in the third rail traction territory the current collection devices of the affected train retracted, before traction power is restored to other trains.

(4) If the fire on a train or on the track causes a train to stop between the stations, passengers shall be evacuated as per the provisions specified in sub-rules (3) to (8) of rule 50, as applicable.

(5) If the incident occurs in a tunnel, the Traffic Controller shall arrange with the Auxiliary Systems Controller for the ventilation system to supply fresh air to the chosen route for evacuation before authorising detrainment of passengers.

(6) If the fire alarm on a station is actuated or a verbal report is received of smoke or fire on the station, the Station Controller shall inform the Traffic Controller and then verify for himself by closed circuit television or actual inspection whether or not the alarm is genuine.

(7) If smoke or fire is present, the Station Controller shall inform the Traffic Controller and arrange for passengers to be evacuated from the area concerned preventing further access and if necessary, the station may be completely evacuated and the traffic controller may be requested to arrange for trains not to stop.

(8) The Traffic Controller shall inform the Chief Controller who shall arrange for the attendance and assistance of the fire fighting services and if necessary the ambulance services.

(9) If a Train Operator or Station Controller observes a fire in adjacent premises that could affect the property of the Metro Railway he shall report the circumstances to the Traffic Controller and the Traffic Controller shall inform the Chief Controller and the Security Controller and maintain normal services unless or until a local inspection confirms
that a potential danger exists.

Flooding –(1) Any Train Operator or Station Controller or the other member of the staff, who observes water accumulating on the track, shall report to the Traffic Controller giving as much detail as possible with respect to location, distance of track affected, and approximate level of water with respect to the rail.

(2) The Traffic Controller shall inform all trains required to pass through the area and requests reports of the state of the water level and if the water level is below the level of rail fastenings, the Traffic controller shall instruct the Train Operator to reduce the speed of their trains to twenty five kilometer per hour when passing through the affected area.

(3) If the water level rises above rail fastenings, passenger train service shall only be permitted under special instructions.

Other unsafe conditions – (1) All Metro Railway employees, and, in particular, Train Operators and Station Controllers shall keep a look out for unsafe conditions on or in the vicinity of the railway track which are as follows:-

(a) damaged or dislodged fixed equipment within the railway right of way.
(b) broken or buckled rails.

(c) displaced or damaged overhead traction power conductors or third rail power conductors, as the case may be;
(d) construction activities adjacent to the track including use of cranes which can swing within 6 metres of the track;

(e) road accidents which might cause or have caused damage to bridges and viaducts.

(f) road accidents which might cause or have caused vehicles or their loads to encroach on the metro railway right of way. and

(g) any other obstruction on the track.

(2) If the Train Operator observes any unsafe condition, he shall report to the Traffic Controller immediately so that action can be taken to minimise the effect and remove the cause.

(3) In the event of an earthquake, the Traffic Controller shall instruct all trains to stop immediately and after such earthquake has subsided, the Traffic Controller may instruct each stranded Train Operator to proceed in Restricted Manual mode at walking speed after examining that the track is safe for train movement and free from obstruction up to the next station: Provided, that in such event, the normal operation of trains may be resumed if all the track and structures are examined, as per Special Instructions.

 

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Metro Rail Speed And Working of Trains Service Regularity https://www.railwaysignallingconcepts.in/metro-rail-speed-and-working-of-trains-service-regularity/ https://www.railwaysignallingconcepts.in/metro-rail-speed-and-working-of-trains-service-regularity/#respond Thu, 29 Oct 2020 08:12:41 +0000 http://www.railwaysignallingconcepts.in/?p=636 Metro Rail Speed And Working of Trains Service Regularity Metro Rail Speed And Working of Trains (1) No person shall drive a train unless he is in possession of a valid certificate of competency and medical fitness. (2) No Train Operator shall be booked to work a train until he has learnt the road and […]

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Metro Rail Speed And Working of Trains Service Regularity

Metro Rail Speed And Working of Trains

(1) No person shall drive a train unless he is in possession of a valid certificate of competency and medical fitness.

(2) No Train Operator shall be booked to work a train until he has learnt the road and signed a certificate that he is fully acquainted with it and for this purpose, he shall be booked for minimum three round trips including one trip during night before being put to work the train independently.

(3) A Train Operator who has not worked on a section for three months or more should be given road learning trips to refresh his knowledge as under:

                       DURATION                                                                 NO. OF ROAD
                     OF ABSENCE                                                          LEARNING  TRIPS 
                       3-6 months                                                                  1 round trip
                    Over 6 months                                                              3 round trips

 

(4) No train shall be driven on a running line from the rear cab except – 

(a) a locomotive working within an Engineer’s Possession under the control of hand signals.

(b) in exceptional circumstances, when authorised by an official not below the grade of Traffic Controller. A look out shall be positioned in such cases at the leading end with the capacity to apply the emergency brake, and the speed of the train shall not exceed ten kilometer per hour in such cases.

(5) In depot, the train shall be always driven from the leading cab in the direction of travel or otherwise the Train Operator in the rear cab shall be instructed by cab to cab telephone by a second qualified Train Operator in the leading end cab.

(6) In depot, where a part consist or damaged train cannot be driven from the leading end, a look out shall be posted at the leading end, the Train Operator shall have the means of sounding an audible warning and, if practicable, the means of applying the emergency brake.

(7) Each train while manned shall show two white lights to the front and two red lights to the rear in the direction of travel.

(8) A stationary train on a running line shall be secured and shall show two red lights at each end of the train.

(9) A train stabled in a depot or siding shall show at least one red light at each end at a double ended siding and at the outermost end in the dead end siding.

Service Regularity

(1) Every effort shall be made by Operations Control Center Staff, station staff and train staff to ensure that scheduled intervals between trains are maintained.

(2) the Traffic Controller shall be responsible for maintaining the services at the scheduled level as far as practicable and for restoring the train services following a delay or disruption.

(3) the Traffic Controller at the Operations Control Center may adjust the timetable and may intervene manually to set and clear routes if the timetable needs to be varied or in the event of a major disruption.

(4) Each Train Operator shall start his train from terminal station as soon as he gets the Departure Order Indication.

(5) Each Train Operator shall start his train from each intermediate station at the time indicated by the Departure Order Indication.

(6) Each Train Operator shall follow any instruction from the Traffic Controller which varies the scheduled timings of his train.

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Metro Rail Advance Signalling System https://www.railwaysignallingconcepts.in/metro-rail-advance-signalling-system/ https://www.railwaysignallingconcepts.in/metro-rail-advance-signalling-system/#respond Fri, 23 Oct 2020 21:01:52 +0000 http://www.railwaysignallingconcepts.in/?p=2514 Metro Rail Advance Signalling System Metro Rail in India Kolkata Metro : The Kolkata Metro is a mass rapid transit system serving the city of Kolkata. It was the first such form of transportation in India, opening commercial services in 1984. Delhi Metro : Planning for the metro started in 1984, when the DDA and the […]

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Metro Rail Advance Signalling System

Metro Rail in India

Kolkata Metro : The Kolkata Metro is a mass rapid transit system serving the city of Kolkata. It was the first such form of transportation in India, opening commercial services in 1984. Delhi Metro : Planning for the metro started in 1984, when the DDA and the Urban Arts Commission came up with a proposal for developing a multi-modal transport system for the city. The Government of India and Delhi jointly set up the Delhi Metro Rail Corporation (DMRC) in 1995. Construction started in 1998, and the first section, opened in 2002. Rolling stock 179 trains, total length of track 189.63 kilometres with 142 stations of which 35 are underground.

Bangalor Metro : Opened in 2010. And Construction started for Mumbai , Hyderabad & Chinnai Metro.

Signalling

1. For ensuring Safe train movement.
2. Signalling is used for increasing line capacity.
3. Signaling is mean of communication to Impart Non Verbal information to Train Operator.

 

Signalling Equipment

Signalling Equipment

 

POINT MACHINE
Point means a connection used to connect one line to another for the purpose of making a movement for one line to other line

1. POINT MACHINE IN DEPOT

POINT MACHINE IN DEPOT

 

 

2. POINT MACHINE IN MAINLINE

POINT MACHINE IN MAINLINE

 

Point Machine: – is a signaling gear which is used for diverting train/ vehicle from one line to another.

Point Position

 

Point Position: – Point has two positions
1. NORMAL
2. REVERSE
ELECTRIC KEY TRANSMITTER

Point Position

(a) NORMAL : – means that Position of a point which is normally set for most of the trains.

 

Normal

 

(b) REVERSE: – means that Position of a point which is not normally set for most of the trains but when operated by point machine can cause train/ vehicle to change to another line.

 

 

REVERSE

 

Track Circuit

1. Track circuit is a device which is used for detecting the presence or absence of train.
2. Apart from detection of train presence, it is used for SACEM (Systeme d’Aide à la Conduite à l’Exploitation et à la Maintenance ) data transmission.

Track Circuit

 

Target point sent to the train to train, OCC, DCC, SCR, SER, etc.

SMARTWAY DIGITAL TRACK CIRCUITS (SDTC) SDTC cubicle, and TWC rack RELAYS/Relay panel

All signal elements like main line signals, depot signals, point machines, shunt signals other then Track Circuits need to be proved by relays. The inputs from the field first come to the relay panel.

Track side ATC Equipment

Track side ATC equipment communicates with the train born ATC for the safe running of the train. ATC cubicle is called 2 out of 3 cubicle (2oo3). It is SIL(Target point sent ) to the train B 4 system. The communication is two way. The Transmission between Track side and Train can be classified as

Track side ATC Equipment

 

STIB

STIB (DL/DLR- Down Link Receptor) Stationary Train Initialization Beacon

 

Antenna

Impedance Bonds

A connection box, usually mounted between the rails, which provides continuity with return signal/current.

Impedance Bonds

 

Signal

 Signal

 

Cab Signal

1. Cab signal is indication provided inside Train Operator’s cab in terms of speed code.
2. Proceed: Speed Code other than zero
3. Stop: Speed code is zero

1.  MMI : Man Machine Interface Odometer speed sensor

Cab Signal

2. DMI : Direct Media Interface

 Direct Media Interface

Fixed Signal

1.A : Route Signal (With Route Indicator Line-1)

Route Signal

Route Signal

Green : Proceed : Route set , locked and the track circuits to the next route signal are clears. (or the two blocks are clear).

Violet : Conditional proceed : Route set and locked ,and the first track circuit after the signal is clear. (or two track circuits of the cross over). or the green aspect is failed or Route Indicator (or repeater Route indicator is not lit if control given for it).

Red : Stop : Route not set and locked ,or the first track circuit after the signal is occupied (or one of the two track circuits for a cross over).

Route Signal 2

 

Shunt Signal

1. The Shunt signal has three lamps to display different indications.
2. There are two types of indications.

3. Two lunar white horizontal lamps : Stop (Normal, ON, restrictive aspect) Route not set and locked, or if the route includes track circuits one of them is occupied.

4. Two lunar white lamps at 45°in the left- hand upper quadrant : proceed (or Clear, OFF, permissive aspect), Route set and locked ,and if the route includes track circuits all of them are clear.

 

Shunt Signal

 

Repeater Signal

Repeater Signal

 

Buffer Stop Signal

Used at
1. the ends of the line ;
2. the ends of the siding in the line and in the depot ;
3. the ends of the test track in the depot ;
4. These signal permanently show red aspect

 

Buffer Stop SignalINTERLOCKING

Interlocking means arrangement of signals, points and other appliances operated from lever frame or panel electrically, mechanically or both in such a way that there operation must perform in proper sequence to ensure safety. In CBI (Computer Based Interlocking)  Monitor and Control Signaling Equipment Track Circuits, Points, Signals, Cycles and Routes

 

System of working

CATC (Continuous Automatic Train Control)
• CATC’s Subsystem :
– ATS (Automatic Train Supervision)
– ATC (Automatic Train Control)
– ATP (Automatic Train Protection )
– ATO (Automatic Train Operation )

Related Speed . Continuous monitoring of braking. Audio visual warning and application of brakes, if necessary. Maintaining safety distance between trains. Monitoring of stopping point. Releasing doors on the correct side of the platform when train comes to a stop.

Operation Control Centre

Signal Set SAFE Way

Signal Set SAFE Way

 

Rail Transport in India – 1849, in 1951 Nationalized , in 1853 introduced . 135,000 km Track, 60,000 Rolling stock, 20 million passengers per day.

Meter gauge 1,000 mm.
Narrow gauge 1,067 mm.
Broad-gauge 1435 mm.
Track gauge 1676 mm.

 

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RAILWAY PLATFORM DOOR INTERFACE UNIT https://www.railwaysignallingconcepts.in/railway-platform-door-interface-unit/ https://www.railwaysignallingconcepts.in/railway-platform-door-interface-unit/#respond Fri, 23 Oct 2020 21:00:06 +0000 http://www.railwaysignallingconcepts.in/?p=1068 RAILWAY PLATFORM DOOR INTERFACE UNIT Introduction: • PEDs are installed in eight stations in Jubilee Line to reduce the possibility of passenger accidents. • The doors are required to be closed at all times and open when a train is correctly positioned in the platform. • Station staff can exercise manual control over the PEDs […]

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RAILWAY PLATFORM DOOR INTERFACE UNIT

Introduction:
• PEDs are installed in eight stations in Jubilee Line to reduce the possibility of passenger accidents.
• The doors are required to be closed at all times and open when a train is correctly positioned in the platform.

• Station staff can exercise manual control over the PEDs for emergency or maintenance purposes by operating an override switch.
• In an emergency, passengers on the train can open the PEDs by hand to exit the train.

• Wayside equipment located in the station platform which acts as an interface between the existing Platform Edge Door Controller (PEDC) and the Platform Edge Door (PED).

RAILWAY PLATFORM DOOR INTERFACE UNIT

Existing Architecture:
• A Platform Edge Door Controller (PEDC) controls the opening, closing and locking of the platform edge door
controller is via a PAC trackside communication loop.

• The PAC then re-transmits the command information via hard-wired relay circuits to the PEDC, which will then open and close the platform edge doors as and when required.

• A screen containing doors is installed along each platform edge with all the doors controlled from a PEDC in the head wall of every platform.

• The PAC transmits continuous signal to the PEDC when activated by the train ATO commands.
1. The first is an ‘open’ activate signal for all the passengers PEDs to open.
2. The second is a ‘close’ activate signal for all passengers PEDs to close.

• An accurate stopping position of the train in the platform is required so that the train comes to a stand at the stop mark and the doors on the train are in alignment with the PEDs.

• This loop transmits information between the ATO equipment on the train and the PAC located in the Automatic Train Control (ATC) cubicle in the SER.

• The ATO will transmit to the PAC command to open or close the doors.
• The train operator achieves this by pressing the ‘open’ or ‘close’ button to operate the train doors.

• When the train doors are opening or closing, the ATO will send a command to the PAC for the PEDC to open or close the PEDs.
• When the PEDs are closed, a latched system is used to prevent them re-opening as the train is exiting the station.

TBTC System:

• The TBTC system will replace the ATO/PAC portion of the existing PED system.
• TBTC monitoring and control of PEDs will be provided by interaction between VCC, VOBC and PDIU subsystems.

• The PDIU will physically interface with the PEDC via relay rack connections.
• Stations equipped with PEDs will have at least one PDIU in the SER as well as docking loop installed trackside.

• As a train docks at a PED equipped station stopping point the VOBC and PDIU will establish communications.
• Each PDIU will support two channels for VOBC communications, one for each platform.

• Stations with additional platforms require multiple PDIUs.Ex: North Greenwich.

PLATFORM DOOR INTERFACE UNIT 1

 

• The relay rack will act as a interface between the PDIU which is a component of a TBTC system and the PEDC which is an existing equipment actually used to operate the doors.

• The relay rack shall continuously report the PED status to PDIU. While the PEDC override key switch is operated the relay rack shall report PED status as Locked and closed to the PDIU irrespective of the actual door status and also illuminate a local indication within SCR.

• When commanded by the PDIU, the relay rack shall command PEDC to open or close the PEDs.

PLATFORM DOOR INTERFACE UNIT 2

PLATFORM DOOR INTERFACE UNIT 3

 

 

 

RAILWAY PLATFORM DOOR INTERFACE UNIT,Existing Architecture, TBTC System

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