Design Modification
1. Modifications are only used once installation has commenced. i.e on issue of installation copy.
2. Modification sheets are issued with the following aims:
a. Expediency of issue
b. Clarity of modification
3. Modification process requires strict configuration control of all modifications made to issued sheets.
4. This is achieved by unique identification and full traceability to the affected drawing sheets.
Mod No: ALC-N392-MOD-xxx-Vy-zzzz Zzzz is the Modification number 0001 to 9999, y volume No., xxx SER acronym.
E.g: ALC-N392-MOD-NOG-V2-0001.

Modification Register
• The Group leader shall maintain a register of modification serial numbers, recording details of the modification.
• Modification Register includes
a. Serial number.
b. Number of sheets within the modification.
c. Date of issue of the modification
d. The issuing ECN number.

e. The source of the modification (DGN, TST, INS, TLL, OTH: Design Office, Test Log, Installation Log, TLL comments, Others, Respectively).
f. Originator’s Reference (e.g. the Test Log number)
g. SCR raised as a result of the originator’s comments/logs.
h. A brief description or other commentary as required.

Production and issuing
* Modification production shall follow the Red/ Green method of design as detailed in RT/E/C/11701 as applied to the main design works.

* Where appropriate one drawing method can be adopted and shall show only an extract of the affected portion of the circuit along with appropriate analysis sheet extracts. If impractical two drawing method shall be used.

* Further, where appropriate, full drawing sheets, including analysis sheets, profiles, etc. shall be permitted to be re-bordered as Modification sheets.
* In all cases, the sheets shall be issued with a full reissue of the index sheets and Revision History sheets, up-issued to the next revision.

Indexing and Revision Control
* The modification is produced on Mod sheets as described earlier and then the index is updated to show the sheets affected by the Mod sheet.

* The Revision History reflects the issuance of the MOD sheet and that the Index and Revision History sheets have been updated.
* The cover, index and Revision History sheets will always bear the latest revision letter. For every mod, these sheets revision will be incremented.

* Should modification arise during the commissioning, the same process of MOD sheet issue would be applied, with a subsequent reissue of the book wiring at next higher Version for As Built.

TLL Acceptance of Design Modification sheets
All modification packs shall be provided to TLL for Acceptance, using the same process as the bookwiring acceptance submission.

TBTC Sheets
•Cover sheet
•Index sheets
•Revision History
•Design Sheets             

WRSL/IMR Sheets
•Cover sheet
•Index sheets
•Design Sheets

Cover Sheet
• Take the previous issued design.
• Up revise the revision in RED.

• Overlay new modification number in BLACK.
• Do not change the Version.
• Remove the stage work note (If any).

Design MOD Process (TBTC Sheets)

Index Sheets

• If the design sheet is updated as part of design MOD then take the related design index sheet.
• Up revise the revision in red.
• “ALL NEW WORK” label to be removed.

• In the design modification column place the MOD number in black.
a) ( G+R) for GREEN & RED Sheet
b) 000X(G+Bu) for GREEN & BLUE Sheet
c) 000X(G+R/Bu) for GREEN, RED & BLUE Sheet
d) 000X(Bu/Bn) for BLUE & Brown Sheet
e) 000X(G+R/Bu/Bn) for GREEN, RED, BLUE & Brown Sheet
f) 000X(R) for RED sheet
g) 000X(NEW) for New sheet
– (Note 000X is Design MOD number)

Revision History Sheet
• Use the previous issued sheet from the MOD/Latest version.
• Up revise the revision in red.
• Mention cover sheet, index (affected) & revision history (affected) sheet’s in BLACK.

• Description column to be updated as per Design Log.
• Also update the DES & CHK names in respective column as BLACK.
• NOTE: Do not put Approver’s name in APV column

Design Sheets (Green Sheet)
• Use the latest issued sheet from the MOD(Red sheet)/Latest version.
• Insert the design MOD cell and update the design MOD number. (For the dual sheet show the both design modification number).

• Change the entire circuit into BLACK.
• Show the recoveries in GREEN.
• Do not Up revise the revision.
– NOTE: Blue/Brown colour also change into BLACK

Design Sheets (Example)

Design Sheets (RED Sheet)

• Copy the green sheet and make it as Red sheet.
• Remove the recoveries.

• Add the new items in RED/BLUE/BROWN as required.
• Do not Up revise the revision.

Cover Sheet
• Copy the previous issued design in black.
• Up revise the revision in red.
• Overlay new modification sticker.

Design MOD Process (WRSL/IMR Sheets)

Index Sheet
• If the design sheet is updated as part of design MOD, then take the related design index sheet.
• Up revise the revision in BLACK eg. AA – AB – AC etc.
• Stick new modification box over previous and sign.

• Design Sheets included as part of modification pack are not to be up revised.
• No need to have Green/Red sheets.
• But “# – note” to be provided in BLACK for design sheets.
− eg. #1 – XXX–TL-0001
− #2 – XXX-TL-0002
− XXX-Stn Name

Design Sheet
• Take the RED sheet from previous modification or design and turn to BLACK
• Carry out red & green modification as per scope
• Add heading “DESIGN MODIFICAION SHEET” in Black.

• Add “NOT TO BE FAXED” label in Red.
• Add red & green legend as like TBTC sheets.
• Include a box on sheet showing modification reference number.
• Do not up revise the revision letter.

Design Sheets (Red Sheet)

Important Notes

• If a new sheet is introduced in the design modification then the revision should be “ – “ & put a “NEW SHEET” label.
• In the NEW sheet “DESIGN MODIFICATION SHEET” heading is not required.
• If there is no recoveries in the GREEN sheet then put the label “NO RECOVERIES ON THE SHEET” in GREEN.

• If there is no addition in the RED sheet (only colour change) then put the label “COLOUR CHANGE ONLY” in RED.
• If the sheet is abolished in the design MOD then in the index description has to be changed as “SHEET ABOLISHED AT REV x” and revision remain same.
Note: x – is the revision of the abolished sheet

Important Notes

• While reusing the abolished sheet number, the revision of the sheet must be the same as abolished revision & put a “NEW SHEET” label.

• While transferring the circuits from one sheet to another sheet put a note in Green sheet as “TRANSFERRED TO SHEET ALC-…….” in GREEN & put a note in Red sheet as “TRANSFERRED FROM SHEET ALC-…..” in RED.

• If it is dual sheet then mention both sheet numebrs.

Signalling MOD Design Process, Design Modification,Modification Register,Production and issuing, Indexing and Revision Control, TLL Acceptance of Design Modification sheets, TBTC Sheets,WRSL/IMR Sheets, Cover Sheet, Design MOD Process (TBTC Sheets), Index Sheets, Revision History Sheet, Design Sheets (Green Sheet), Design Sheets (Example), Cover Sheet,Design Sheet,Design Sheets (Red Sheet)

1. Traffic control system (TCS) or centralized traffic control (CTC) is a block system under which train movements are authorized by block signals whose indications supersede the superiority of trains for both opposing and following movements on the same track. FRA 236.828

2. Signal control – train movements are controlled by signal indication, usually by a dispatcher at a remote location via codeline, modem, or data radio.

Definitions

 Control – A request sent from the dispatch office for an operation of a device at a control point.

1. A request for a switch to throw or a signal to clear.

2. This is either a direct request from the dispatcher or an automated request from the control computer. (A stored route)

Indication – The information sent from the control point conveying the events that occur at that control point.

1. A signal clearing or track circuit becoming occupied.

2. This is initiated by any change of a condition monitored at the control point.

Vital circuits – circuit that directly affects the safety of train operation. (For example, a signal or switch control circuit)

1. Controls are routed through vital relays, which check the integrity of the signal system, before allowing a signal to clear or a switch to throw.

Non-vital circuit – A circuit whose failure would not cause an unsafe condition to exist. (For example, a control or indication circuit) Indications are used as a graphical representation in the dispatch office, to allow the dispatcher to “see” what is occurring in the field.

In CTC territory, trains are governed by signal indication.

1. The dispatcher controls trains by determining which signals to send a request to clear.

2. Signals are interconnected so that no two signals will be allowed to clear into the same block between control points in opposite directions.

Sequence of Events of Events

1. Dispatcher requests an operation of a component at a control point.
2. Control is sent via the necessary communications device.

3. Control is received at control point.
4. Vital circuits are checked and, if safe, the operation is completed.

5. Control point sends indication to dispatcher.
6. Indication is displayed on the dispatcher console.

Dispatch Office

1. Dispatch offices have evolved from toggle switches, push buttons and light bulbs to computer workstations with “point and click” interfaces and graphical displays.

2. Dispatchers select a device to control and the computer determines the means to send that request to the field
control point.

3. The control is then sent via modem, microwave, data radio or any combination of communication devices.

4. Indications are received from the field control point, interpreted, and displayed as an image for the dispatcher.

In the dispatch office are a variety of troubleshooting tools available to the signal department employees.

1. Data recording of dispatcher requests and keyboard commands.

2. Data recording of controls and indications from the “codeline”.

3. Monitoring capabilities for on-site personnel.

“Office logic” may be used to prevent unsafe controls from being sent from the dispatch office.

1. For example, if an eastbound signal is requested the computer would not allow a request for a switch to throw in that route.

2. This is not a fail-safe system.

3. This is not used to replace the vital logic of the field control points.

Field Control Point

1. The control point receives the control from the dispatcher.
2. Vital circuits are checked for conflicting signals, signals “in time”, switches in correspondence, etc.

3. If it is safe to operate device requested, the operation occurs – switch throws, signal clears, etc.
4. When operation is completed, the control point sends an indication to the dispatch office, updating the office of the current conditions at the control point.

In addition to the vital controls available to the dispatcher are useful tools for the signal personnel.

1. Remote control of switch heaters. (Snow melters)
2. Remote indication of power failure.

3. Remote indication of fire or break-in.
4. Dispatcher availability of a maintainer call.

Signals at control points are absolute signals

1. Signals normally display a stop indication until requested by the dispatcher or control operator.
2. An automatic block system (ABS) is used between control points.

3. Block occupancy indications are sent to the dispatcher or control operator from the adjacent control points.
4. Hand-throw switches in a control point or in the block between control points must be protected with an electric lock or an exiting signal.

Centralized Traffic Control Summary

1. CTC allows for a safe, efficient, and cost effective means of controlling trains.

2. CTC increases track capacity and train speed by expediting train movement by lining routes and clearing signals prior to a train’s arrival at a control point.

3. CTC allows a single dispatcher or control operator to manage a large section of track, interconnected signals and control points.

4. CTC allows a redundant safety system to prevent unsafe requests from being sent to the field control point.

Introduction to Centralized Traffic Control, Signal control,  Control, Indication, Vital circuits, Non-vital circuit,Sequence of Events of Events, Dispatch Office,Field Control Point,Signals at control points are absolute signals

SESSION 7

* APPLICATION PROGRAM TEXT EDITOR

* FILE NAMING

* OPERATOR

SESSION 8

APPLICATION PROGRAM STRUCTURE

• BAMRA APPLICATION LOGIC – C1
• BAMRA APPLICATION LOGIC – C2

SESSION 9

APPLICATION PROGRAM STRUCTURE

• BAMRA APPLICATION LOGIC – C1
• BAMRA APPLICATION LOGIC – C2

SESSION 10

SYSTEM INITIATION LOGIC

• BAMRA APPLICATION LOGIC – C1
• BAMRA APPLICATION LOGIC – C2

SYSTEM INITIATION LOGIC:

ASSIGN    ~DIG_ON * DIG_OFF

TO CPS.ENABLE;

ASSIGN    CPS.STATUS * CPS.STATUS.ISI

TO CPS.STATUSJ2;

// STR 2 SEC

ASSIGN    CPS.STATUSJ2 * ALSR_DN *

~SYSINITTMR      TO CPSJR;

ASSIGN    CPS.STATUS * (CPS.STATUS.ISI +

SYSINITTMR)      TO SYSINITTMR;

// STP 130 SEC

ASSIGN  SYSINITTMR      TO SYSINITTMR1;

SESSION 11

SAMPLE INTERLOCKING LOGIC

• BAMRA APPLICATION LOGIC – C1
• BAMRA APPLICATION LOGIC – C2

ROUTE INITIATION LOGIC:

ASSIGN    ~1ANRR * (1.C1ALSR + 1ANNR)

TO 1ANNR;

ASSIGN  1BNNR * 1CNNR * 7NNR * OV7NNR *

9NNR * OV2_9NNR * SH4ANNR *

SH4BNNR * SH4CNNR * SH4DNNR *

SH5NNR * SH7ANNR * SH9NNR *

C1ANNR * C1BNNR * C1CNNR *

(1GNR * UMUNR + 1ANRR) *

(~1GNR + ~EGGNR) * ~1.C1UYR4

TO 1ANRR;

POINT INITIATION LOGIC:

ASSIGN      (CH1NR * (1TCPR * 4TCPR + (~1TCPR +                                                                                                                                                              ~4TCPR) * EWNR) * ~EW_N.R_CR * 16WLR *                                                                                                                                                     (16WR * WWNR + (~16WR + ~WWNR * ~WWRR)                                                                                                                                           * 16WWR * ~EWNR * 16NLR) * ~16NWKR +                                                                                                                                                       16WNR.ISO * (~16WLR + ~16RLR * (~WWRR                                                                                                                                                   + ~16WR + 16NLPR)) + ~16WNR.ISO *                                                                                                                                                                 16NWK1R.ISI * ~16RWK1R.ISI * CPSJR) *       ~16WRR.ISO    TO 16WNR.ISO;

ASSIGN    (CH1NR * (1TCPR * 4TCPR + (~1TCPR +                                                                                                                                                                ~4TCPR) * EWNR) * ~EW_N.R_CR * 16WLR *                                                                                                                                                    (16WR *  WWRR + (~16WR + ~WWNR * ~WWRR)                                                                                                                                          * 16WWR * ~EWNR * 16RLR) * ~16RWKR +                                                                                                                                                        16WRR.ISO * (~16WLR + ~16NLR * (~WWNR +                                                                                                                                               ~16WR + 16RLPR)) + ~16WRR.ISO *                                                                                                                                                                       16RWK1R.ISI * ~16NWK1R.ISI * CPSJR) *                                                                                                                                                          ~16WNR.ISO    TO 16WRR.ISO;

ROUTE SETTING LOGIC:

ASSIGN    CH1NR * CH2NR * 21LXNR * (16NWKR *

(18NWKR * 26NWKR * 27NWKR * CH5NR

* 28LXNR * 1ANRR * ~1ANNR * OV5NRR

* ~OV5NNR + 18RWKR * 1BNRR *

~1BNNR * (OV1_9NRR * ~OV1_9NNR *

26NWKR + OV2_9NRR * ~OV2_9NNR *

26RWKR * 27NWKR * CH5NR * 28LXNR))

+ 16RWKR * 17RWKR * 25RWKR *

27RWKR * 19NWKR * 24NWKR * 18NWKR

* 26NWKR * 1CNRR * ~1CNNR * OV7NRR

* ~OV7NNR * CH3NR * CH4NR * CH5NR

* 20KTNR * 28LXNR) * ~C1UCR  TO 1UCR;

ASSIGN    ~1HR.ISO * ~1BUR.ISO * ~1CUR.ISO *

~1DR.ISO * ~1DECR.ISI * ~1HECR.ISI

* ~1UECR.ISI * ~1UCR * ~C1HR.ISO *

~C1HECR.ISI * ~C1UCR * (1T1PR.ISI

* 1T2PR.ISI * 1TCPR * (7TCPR +

16WRR.ISO) * (4TCPR + 16WNR.ISO) *

(1.C1UYR1 * 1.C1UYR2 * 1.C1UYR3 *

1.C1UYR4 * SYSINITTMR + 1.C1JSLR *

1.C1JR) + 1.C1ALSR)    TO 1.C1ALSR;

SIGNAL CLEAR LOGIC

ASSIGN      CH1NR * CH2NR * 21LXNR *

21.2GFRR.ISI * 1.C1TSR * ~1.C1ALSR

* 1.C1JBPR * ~1.C1UYR1 * ~1.C1UYR2

* ~1.C1UYR3 * ~1.C1UYR4 * 1UCR *

~C1COUR * 1T1PR.ISI * 1T2PR.ISI *

1TCPR * (16NWKLR * 7TCPR *

(18NWKLR * 26NWKLR * 27NWKLR *

UMTPR.ISI * 5TPR.ISI * 3TCPR *

CH5NR * 28LXNR * 28.2GFRR.ISI *

1ANRR * OV5NRR * ~OV5SR *

~1UECR.ISI * 5ECPR + 1BUR.ISO *

1UECR.ISI) + 1CUR.ISO * 1UECR.ISI)

* (~1GNR + 1HR.ISO) * ~C1HR.ISO         TO 1HR.ISO;

SESSION 12

COMPILATION TECHNIQUES

TEXT EDITOR

FILE NAMING

File Title

Application Logic for C1 MLKII

BMB_C1_D01  Design Version

BMB_C1_T01  Factory and Site Testing Version

BMB_C1_S01   Service Version

Application Logic for C2 MLKII

BMB_C2_D01  Design Version

BMB_C2_T01  Factory and Site Testing Version

BMB_C2_S01  Service Version

Introduction

1. Public Information Display System (PIDS)
2. The purpose of PIDS is to display at station concourses and platforms on-line information about scheduled train arrivals and departures and other general purpose messages (normal and emergency) such as smoking is prohibited, evacuation messages etc.
3. It displays information in any combination of English text, Hindi text, numerals, animated graphics, punctuation and symbols in real-time.

Operational Control Center

OCC Theatre

FOTS

                                                     Stations

SCR                                                 SCR                                             SCR
Display Boards                     Display Boards                         Display Boards
Display Boards                     Display Boards                         Display Boards
Display Boards                     Display Boards                         Display Boards
Display Boards                     Display Boards                         Display Boards

PIDS/PAS functional blocks

It consists of the following functional blocks:

The Operational Control Centre (OCC).
1. The OCC is the global control centre for the PIDS/PAS system.
2. From the OCC system wide control of SCRs is possible.

The Station Control Rooms (SCR).
1. The SCR is the local PIDS/PAS installation exists in each station.
2. It manages the local PIDS/PAS system of that station.

Operational Control Centre
FOTS

Master                      OCC LAN                         PIDS/PAS
Clock                                                                          Server

AT S Central                                        PIDS/PAS
Server                                                      MMI

SCADA                                                   PIDS
Server                                                   Backup

PAS
Backup

Operational Control Center Configuration

PIDS/PAS Server

1. The central server is located in the OCC. This server, with the necessary back-up and redundancy modules is connected, via the central router to the central ATS server, to the Local ATS servers, to the SCADA server, and to the Master Clock unit. The PIDS central server is common to the PAS central server.

2. The central server is composed of two machines configured as a Windows NT cluster, with shared disk storage. When one machine fails, the services are automatically started on the backup machine, which reads the state information from the shared disk array.

3. The central server and the station servers are synchronized via the clock distribution system.

Master Clock
The Master clock provides for the system wide time synchronization.

ATS Central Server
The ATS server sends information on train arrivals and departures to PIDS local ATS servers.

SCADA Server
The SCADA server receives and manages  alarms generated by PIDS/PAS.

PIDS/PAS functional blocks

PIDS/PAS Servers
The two servers at a single station are symmetric: one is active, and the other is on hot stand-by. Both systems receive all the external events and update the local state, but only the active system sends output to the displays or loudspeakers. Both systems are constantly monitoring each other for a failure. When one system fails the other automatically takes on the active role. When the changeover occurs an alarm indication (alarm pop-up window and audio signal) is shown on the active MMI.

Submaster Clock
The Submaster Clock provides a local backup for the system clock in case the latter is unserviceable .

ATS Local Server (LATS)
The local ATS server receives and manages ATS data from the central ATS server.

The Main Window of PIDS/PAS Application

The main window is divided into different areas by function. Selection area Current Station area Alarm area

The Display Boards Tree (3)

This panel allows us to select or deselect display boards, in order to, send a message.

The Display Boards Tree (4)

The Alarms Panel (7)

The Alarm Panel displays alarms for:
  Equipment alarms.
Display boards.
Public Address Zones.

Communication with other systems.
1. Internal PIDS alarms (i.e. disk full).
2. Operational alarms (i.e. message priority conflict).

OCC/SCR Synchronization

Public Address System(PAS)

PAS provides broadcasting of voice messages to passengers / staff in all stations, depots and OCC. It can also be used for emergency evacuation broadcast in case of emergencies.

1. The PAS announcements are co-ordinated automatically with PIDS for Real Time Passenger Audio Broadcast.
2. PAS support :

3. Messages announcements in HINDI and English or any combination of these languages.
4. Different Live or Recorded announcements to separate Zones or Group of Zones simultaneously within a station.

5. Announcements from Designated Hand Portable Radios to a set of pre-defined Zones at each station.

Four Major Types of Messages

Fixed Message
-Smoking is prohibited in the entire station.

Pre-formatted with data to be added.
1. This station is…………
2. Due to ……..failure, the arrival of the trains shall be
delayed.

Instantly recorded messages.
Live audio broadcast.
1. According to situation, such as for crowd management
in case of accident.

Message Priority

1. Instantly created / pre-formatted message relating to emergency like fire etc from the SCR.
2. Instantly created / pre-formatted
message relating to emergency like fire etc from the OCC.
3. Train arrival / departure related messages triggered automatically by the TC&S system.

Alarms (Major & Minor)

1. Loss of the entire PIDS facilities at a location.
2. Loss of clock synchronization.
3. Power supply unit failure.
4. Loss of one side of a display board.

5. Message priority conflict.
6. Failure of communication link between OCC and station
PIDS.
7. Loss of both sides of a display board.

PIDS alarms and their possible causes.

Components of PAS

Codec
Telcommander
Amplifiers
Gate Keeper
Zone-8 M
Noise Level Controller (NLC)
Loudspeakers

Codec

Codec is a device that encode and decode the information from digital to analogue signals. It does this by using two Xchanger cards (one is master, located in the OCC server and other is slave, located at each station client server).

Telcommander

Its main task is to interface the Radio System via the PABX, allowing the portable Radio units to address the PAS.

Amplifiers

Signal sources like microphones, CD players, cassette DAT and MiniDisc recorders, do not have the capacity to produce enough energy to directly feed a loudspeaker. It is therefore necessary to use an amplifier that transforms the low power signals of the signal sources in signals with sufficient power to feed the system loudspeakers.The numbers of amplifiers are variable according with the number of physical zones used in each station. The standard procedure is to install one amplifier by zone, and n loudspeakers per zone

Gate Keeper

This equipment is used as an amplifier and loudspeaker controller that performs the
following tasks:
1. Detect and replace any malfunctioning amplifier.
2. Inform the status of each amplifier and possible cause of failure.
3. Distribute the audio signal directly to the loudspeakers.

Zone 8 Selector

1. Dispatch messages to the required zones, respecting the priority scheme between terminals.

Noise Level Controller (NLC)

The human and traffic conditions affect the levels of background noise. Therefore, in order to deal with this issue carefully, the
system will adjust the volume of the announcements to a higher level than the background noise, by using the NLC and NLC sensors.

LC gate interlocking method – I

1. The level crossing annunciation relay (LCAR) is kept normally energized in the gate lodge when no route over the level crossing has been set.

2. Any route is set, the concerned ASR/TRSR/TLSR drops which in turn de-energizes LCAR.

3. This causes the road signal on either side of the level crossing to display red aspect and the bells also start ringing.

4. The Gate-man closes the gate and locks it, by taking out the key.

LC gate interlocking method II

1. SM communicates to the gateman on phone to close the gate.

2. The gateman closes the gate, locks the boom and extracts key.

3. The gateman inserts the in key in EKT and turns it clockwise to transmit control.

4. There by LXR relay energizes & sticks through its own front contact.

Energisation of LXR relay at gate lodge energizes LXCR at relay room.

* With LXCR energized, through LXPR back contact B12 flasher supply gets connected to LXK(w) indication and it starts flashing on the panel.

* Then SM acknowledges by turning the LC control knob to normal.

The moment LX22 knob is  normalized, LX22 RR drops.

Through LX22 RR drop & LXCR up contact, the 22 LXPR picks up, then SM clears the signal.

Through LX22 RR drop & LXCR up contact, the 22 LXPR picks up, then SM clears the signal.

* The moment signal is cleared, the ASR concerned drops which ensures the 22LXFR to drop.

* There by as long as the signal is in taken off condition, LXYR does not pick up and there by gateman cannot open the gate, even if SM inadvertently turns the LC control knob to reverse.

Interlocking of Level Crossing Gate, LC gate interlocking method – I, LC gate interlocking method – II,LCAR, Gateman, LXR relay, LC control knob

Production/ Batch tests 

The following test will be performed on every manufactured batch of cable.

Spark test:

• The test procedure shall be as defined in LU specification E4156. The test shall be performed on the conductor and screen insulation during manufacturer.

• Voltage withstand and insulation resistance test on complete cable(tested dry). The conditioning, test procedure and results supported shall be as defined in LU specification E4156. The test shall be performed on the entire manufactured length of cable. No insulation breakdown shall occur. The insulation resistance shall be atleast 350 mega ohms per kilometer.

Production/ Batch tests:

• Voltage and insulation resistance test on cable components (tested wet). The conditioning, test procedure and results supported shall be as defined in LU specification E4156. No insulation breakdown shall occur. The insulation resistance shall be atleast 350 mega ohms per kilometer.

Conductor resistance test:

• The test procedure shall be defined in LU specification E4156. The test shall be performed on the entire manufactured length of cable. The conductor resistance shall be in accordance with the manufacturer’s design.

Life expectancy:

• The cables once installed shall remain in constant service for an expected 40 years as per LUL specification E4156.

Cables Availability:

Vital concentric signalling cables
• 1 pair
• 3 pair and
• 7 pair

Shielded multicore cables 1.0 mm²
• 2 core
• 4 core
• 6 core
• 7 core
• 12 core
• 16 core and
• 27 core

Cables Availability:

Shielded Multi core cables 1.85 mm²
• 2 core
• 4 core
• 6 core
• 8 core
• 10 core
• 16 core
• 19 core
• 27 core and
• 37 core

Cables Availability

Flexible Screened Multi core cable
• 2 core
• 4 core
• 6 core
• 7 core
• 10 core and
• 12 core
Track connection cable
• 1 core
Track crossing cable
• 5 core
• 10 core

Cable Routes:

• Vital signalling cables shall be kept separate from power cables and, where possible, from control systems and communications cables, e.g. by running in separate shelves of a cable run. (Cat 2)

• The route shall have the capacity to hold all the required cables, together with a 20% spare capacity to cover future needs.(Cat 2)

Design Consideration:

• All track side signalling equipment shall be connected locally to the main track side signalling cables via track side disconnection boxes to facilitate ease of installation, maintenance testing and fault finding.

• All equipment requiring greater than a two wire (plus earth) connection shall be connected via a keyed plug and socket (or equivalent) system which is constructed to a grade of appropriate integrity.

Other Consideration:

a) All cable types shall be identifiable by examination of the sheaths.
b) Cable routes shall be designed to suit the mechanical characteristics of the cable and the installation techniques to be employed. When utilising exiting cable routes, the mechanical characteristics and installation techniques shall be selected accordingly.

c) Where cable routes cross the track they shall be in either overhead runs or in purpose designed cable ducts which fully protect them and do not require the cables to be disturbed during track renewal.

d) With the exception of main power supply cables, all cables entering and leaving signalling equipment rooms, signal apparatus boxes and wayside kiosks shall be terminated on separate cable racks in order of their core numbers on a combined terminal or disconnection, or terminal or fuse links. Each wire shall be capable of being individually disconnected and isolated without removing the wire itself. These links shall be easily accessible for test purposes. Each link or terminal shall be identified and labelled. Power supply cables shall be terminated by a means appropriate to their size and current capacity.

Internal Wiring:

1. All wires shall be terminated.
2. Every end of a wire shall be labelled at the ends of its termination points. The label shall be of a form which cannot be removed without disconnecting the wire.

3. Wire racking shall be earthed and provision made, where practicable, for the isolation of individual racks for fault finding.
4. No joints or splices of any type shall be permitted in wires between terminations.
5. Redundant wiring shall be removed. In the event that a concession is granted to allow the non removal of a wire, then that wire shall be so identified with a label.

Where it is not practicable to physically remove disconnected wiring, the ends shall be cut back ,capped and secured

Circuit requirement

1. Circuits leaving or entering the SER shall be protected by links or isolators. These links or isolators shall be of a type capable of being secured in the isolated condition.

2. Where there is significant risk that the circuits may come into contact with 600V traction rails (e.g. track circuits rail connections) then the links or isolators shall be replaced by fuses or suitable protective devices. Links, isolators, fuses or MCB’s used at the entry point of SER’s on new installations shall provide touch protection against electric shock.

3. They shall also incorporate touch protected connection points on both sides of the isolation to permit a remote switch to be wired across the isolator for simulation purposes during testing, and for the application of test instruments during fault finding. These connection points shall permit the rapid disconnection of the simulation facilities without disturbance to the permanent wiring. The exact form of connection shall be agreed with the Trains System Engineer.

4. A maximum of two wires shall be connected to any one terminal except on diagrams where terminals are provided for multiple connections.
5. A minimum of 10% spare terminals shall be provided on each terminal block on the rack. Terminals used to terminate spare multi core wires shall not be considered as spare terminals.

6. There shall be only one feed per circuit.
7. Where plug connections are used, the wiring shall be arranged such that no voltage is present on exposed pins when disconnected. The plug connectors used shall be mechanically keyed to prevent improper insertion and identify equipment of compatible types.

8. Cable cores, whether main cables, tail, or multi cores shall be terminated. It is not permitted to cut back spare cores in SER’s containing safety wiring.

Production Validation:

1. No cables or wire shall be supplied unless a formal ‘Authorised to supply product’ letter covering the specific cable or wire concerned has been issued by LUL’s Standards Engineer or the materials engineer of an Infraco.

2. Grandfather rights shall not be an acceptable alternative to an ‘Authority to supply product letter’ issued as a result of successful product validation to current standards.

3. For cables or wires that are not already covered by an ‘Authorised to supply product’ letter reference should be made to E4156 for the testing and documentation that must be submitted by the supplier to Thales.
4. Copper conductor resistances should be in compliance with BS6360. The referenced typical PICO values are a guidance for installers only.

TYPE TESTS:

1. The details of the type tests required are specified in E4156 (Appendix B & C).

2. The requirements of 2-01001-002 for fire performance supersede the smoke emission, toxicity and flammability requirements of E4156 or those found in any of the particular cable specifications referenced.

3. Suppliers attention is drawn to the relevant clauses in E4156 concerning the restrictions on acceptable testing facilities.

Fire Performance Requirements

1. The fire performance requirements for cables on London Underground infrastructure are extremely stringent, refer to LUL Standard 2-01001-002 A1, Fire Safety performance of materials.

2. The Supplier will be required to conduct type tests, in accordance with E4156 and 2-01001-002, Fire Performance, in particular covering the three main areas of Flammability, Smoke Emission and Toxicity.

3. The Jubilee and Northern Lies are predominantly tube section and therefore LS0H sheaths and non-PVC insulation will be a standard requirement of most cables.

Production/ Batch tests, Spark test, Conductor resistance test,Life expectancy,Cables Availability, Flexible Screened Multi core cable, Cable Routes,Design Consideration,Internal Wiring, Circuit requirement,Fire Performance Requirements

The requirement of cable conduction is to be determined depending upon the circuits run from CT Room /Relay room function. Separate cable line wise and if necessary, function wise are laid from relay room /CT room to facilitate easy testing of cable without much distraction to the traffic.

Cable size to be determined by keeping spare conductors to a minimum of 20% of total conductors used inn, each cable wiring between the outermost facing point of the station and a minimum of 10% of the total conduction used in the each cable working beyond the points area upto the signals. The approximate cable requirement for a typical four a line station on a double line section and a 3 line station on a single line section.

Type of cable                         Double line                Single line
Signalling cable 24 core                9 kms.                            1 kms
Signalling cable 19 core               10.6 kms.                       2.4 kms
Signalling cable 12 core               10.5 kms                        12.7 kms
Signalling cable 6 core                  5.7 kms.                        3.3 kms
Power cable 10 Sq                          8.6kms.                         7.7 kms

(Aluminum conductor)

Numbering of cable is done in ascending order right hand side of the cable core distribution plan

A cable distribution plan for a 4 line station on a double-line section is attached for reference.

Definitions:

Aspect – any valid visual indication of a signal as displayed to the driver

Aspect sequence – The order in which the aspects of successive signals are displayed to the driver

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

STANDARD THREE ASPECT SEQUENCES

GREEN – YELLOW – RED SIGNAL

STANDARD THREE ASPECT SEQUENCES

* A driver, running under authority of a green aspect in a three-aspect section of line, shall be warned of a stop aspect by the standard three aspect sequence. the minimum signal spacing distances between the yellow and red aspects for various speeds are set out in GK/RT0034.

* Where distances between successive stop signal is more than the maximum permitted by GK/RT/0034, separate distant signals shall be provided.

* Where the permissible speed of trains is greater than 100mph, four aspect signalling shall be considered.

GREEN – DOUBLE YELLOW – SINGLE YELLOW – RED

STANDARD FOUR ASPECT SEQUENCE

MODIFIED THREE ASPECT SEQUENCE

Where it is necessary to position signals such that the required spacing between a YELLOW and a RED aspect in the standard three aspect sequence cannot be provided, sufficient warning of the stop aspect shall be provided by means of one of the following:

1. An isolated standard four aspect sequence (preferred method)
2. Approach control from red of the previous signal to the signal with sub-standard spacing
3. The imposition of a speed restriction.

MODIFIED THREE ASPECT SEQUENCE

1. ISOLATED FOUR ASPECT SEQUENCE (PREFERED METHOD)

2) Approach control from red of the previous signal to signal with sub-standard spacing

MODIFIED FOUR ASPECT SEQUENCE

STANDARD FOUR ASPECT SEQUENCES

A driver, running under authority of a green aspect on a four aspect section of line, shall be warned of a stop aspect by the standard four aspect sequence.

The minimum signal spacing distances between the double yellow and red aspects for various speeds are set out in GK/RT0034.

Green – Double Yellow – Single Yellow – Red

Where it is necessary to position signals such that the required spacing cannot be provided between a Double Yellow and a Red aspect in the standard four aspect sequence, Double Yellow aspects shall be additionally displayed at one or more preceding signals such that minimum signal spacing distance is provided between the outermost Double Yellow aspect and the Red aspect.

• Green – Double Yellow – Double Yellow – Single Yellow (*) – Red

* Train Protection System fitted as a minimum to this signal

• As an alternative to above – restrict the permissible speed

CHARLES WEIGHTMAN’S RECOMMENDATION

Where it is necessary to position signals such that the spacing between the single yellow and the red aspect does not meet the requirement for the 4 aspect sequence (one third of the applicable signal spacing distance), then one of the following modified aspect sequence shall be adopted.

Green – Double Yellow – Single Yellow – Red/controlled to Single Yellow – Red

Green – Double Yellow – Single Yellow – Single Yellow(*) – Red (*) TPWS

ASPECT SEQUENCE TRANSITIONS

Segregation of three and four aspect sequence:

* The number of transitions between three and four aspect signalling shall be kept to a minimum

* It is permissible for an isolated four aspect sequence to be displayed in an otherwise three aspect sequence

AT THE TRANSITION ONE OF THE FOLLOWING ARRANGEMENTS SHALL BE APPLIED

* THE FIRST FOUR ASPECT SIGNAL DISPLAYS A SINGLE YELLOW UPTO THE NEXT SIGNAL AT RED OR A DOUBLE YELLOW UP TO THE NEXT BUT ONE SIGNAL AT RED

* THE FIRST FOUR ASPECT SIGNAL SHOWS ONLY RED/DOUBLE YELLOW/GREEN AND ADDITIONAL DISTANT SIGNAL IS PROVIDED BETWEEN IT AND THE  NEXT STOP SIGNAL AHEAD

* THE FIRST FOUR ASPECT SIGNAL IS APPROACH CONTROLLED FROM RED TO YELLOW WHEN THE NEXT SIGNAL AHEAD IS AT RED

PROHIBITED ASPECT SEQUENCES

Successive signals shall not simultaneously display the following:

a.A red aspect immediately preceded by any colour light aspect other than a single yellow aspect

b.A single yellow aspect followed  by any aspect other than  red, as permitted in modified sequence

Double line block instrument interface with the panel

The entry of the train onto the block section is jointly controlled by the entry and exit points of the block section. The driver is authorized to proceed into block section by the signal controlling the entry into the section. This working could be the ABSOLUTE BLOCK system stem or AUTOMATIC BLOCK system.

Essentials of Absolute block :
“Where trains are worked on absolute block system “

a) Ntraino  shall be allowed to leave a block station unless Line clear has been received from the block station in advance, and

b) On double lines, such line clear shall not be given unless the line is clear not only upto the first stop signal at the block station at which such line clear is given but also for an adequate distance beyond it .

c) On single, such shall not be given unless the line is clear of trains running in the same direction not only upto the first stop signal at the block station at which such line clear is given but also for an adequate distance beyond it, and is clear of trains running in the direction towards the block section to which such line clear is given. The adequate distance referred shall not be less than 180 Mts

d) The whole of the last preceding train has arrived complete; and all necessary signals have been put back to „ON‟ behind the said train.

Block working on double line section

On request from sending station (station-B) station master at station-A will turn the block handle to „Line clear‟ (L-C) position if he is ready to receive the train. LC contact of the block handle energizes LCR. Line clear indication (LCKE appears). The first stop signal (home) is at „ON‟ (RECR↑). The relay GNSR will pick up & switches on the line circuit BPR at station B to pick up. BPR is a polarized relay, thus is gets attracted to line clear side & Bottom Galvo at receiving station A & top Galvo needle indicator at station B turn to the „line clear‟ position.

LCPR is energized through prolarized relay contact on LC side provided the last stop signal displays the „ON‟ aspect. The advance starter can then be cleared for dispatch of train duly proving that the block section including over lap is clear (VPR-UP). When the train crosses advancer starter, TPIR picks up registering train entering the block section. This is accompanied by an audio-visual alarm at the sending station. The buzzer can be stopped by pressing the „ACK‟ button.

Information is then passed on to station A who will turn the block handle to „TOL‟ position. This sends both the galvos to change to TOL position. SR at station B gets energized & remains in that state.

At the receiving station A, when the home signal 1 is cleared, ZR picks-With the sequential proving of ITP & ITPI, BSR & BSPR pick up. Now when block section is clear on complete arrival block clear indication is given. & the block handle can be brought to „line closed‟ position thereby, completing the block operation.

In the event of failure to turn the handle to TOL upon train entering section, auto TOL feature has been  incorporated. As a result TOLR will be picked up when train arrives, ASM gets auto-TOL buzzer/indication. The station master at station A will be forced to turn the handle to TOL. Then through special contact of TOL, BTSR relay picks up. This will in-turn energise the lock and the instrument can be turned to line clear from TOL. This operation is recorded by an electronic counter in addition to audio-visual alarm. Detailed circuit of the block working is shown below.

What is Treadle?

A treadle is a mechanical or electrical device that detects that a train axle has passed a particular location. They are used where a track circuit requires re-inforcing with additional information about a train’s location, such as around an automatic level crossing, or in an annunciator circuit, that sounds a warning a train has passed an exact point. The important difference between a treadle and a  track circuit is that while a track circuit detects a train over a distance as long as several kilometres, a treadle provides pin-point detection.

Types of Treadle

Single Arm treadle:

Treadles are available in two styles, 59 and 69. They are readily identified by the profile of the actuating arm. See figures 1 and 2.    

Figure 2 Style 69: Available as “Forfex” – (double arm)

The “Cautor” (single arm) treadle may be of either style 59 or 69.

The “Forfex” (double arm) treadle is only available as a style 69. There are different versions of the “Forfex” treadle according to the direction of travel that is to be detected.

Directional Treadles

“Forfex” type double arm treadles are available in different configurations: bi-directional (standard model) or uni-directional.

The bi-directional model has two independent reversing contacts, one on each armcorresponding to the two directions of travel. This is the standard model and will detect trainsrunning in either direction.

When the two independent reversing contacts are mounted on one arm the treadle becomesuni-directional. The treadle will only detect trains running in one direction, i.e. from A to B or from B to A.

The direction of detected travel cannot be changed on site. Treadles of each configuration (A to B and B to A) will be required for opposite directions of travel.

The direction of detected travel will be indicated by either a red painted arrow or a red oblong metal label. One end of the metal label will be extended to form a point.On the bi-directional model the label will be pointed at both ends. The painted arrow will have a head at each end. The arrow or label will be found on the exterior of the terminal access cover.

“Cautor” single arm type treadles are bi-directional and detect trains running in either direction

Installation of Treadles

It is recommended that treadles are not installed within 3 metres of a rail joint. This is to minimise vibration, which can cause fixings to loosen, cables or wires to chafe or break.

At existing installations where loosening of fixings or damage to cables and wires is a problem, the proximity of a rail joint may be the cause.

If there is a rail joint within 3 metres, do not move the treadle as the correct operation of equipment could be affected. Advise your manager, so that the necessary arrangements can be made for the design to be checked to ensure continued correct and safe operation.

Actuating Arm – Setting The Position                     

The height is measured vertically between the portion of the actuating arm that makes contact with the wheel flange and the rail level. The rail level is determined by stretching the bob weighted string over the top of the two rails of the relevant track.

For a type 59 Treadle – the top of the arm should be 11 mm (±1 mm) below rail level.

For a type 69 Treadle – the top of the arm should be 16 mm (±1 mm) below rail level.

For both types – the end of the arms should be 10 mm (±2 mm) from the running edge of the rail.

Treadle Renewal

Treadles should be renewed before they wear to the point that there is a risk of failure. The rate of wear is related to line speed, traffic density, vibration and arm return times. The arrangements for determining the frequency of change will be as laid down in local instructions.

 If the wheel flange contact arm shows wear of 50% (3.5 mm) or more of its diameter it should be reported to the manager and arrangements made to change the treadle. The slot in the Treadle Gauge should be used to perform this check.

Timing Adjustment – General

The manufacturer recommends that the time taken for the depressed arm to rise fully is 8 seconds (at 20oC). At this setting the timing can be expected to remain constant over a wide temperature range.

If the time setting is reduced the wear on the treadle will be increased as the treadle actuating arm will be struck more frequently by the wheel flanges.

Timing Adjustment – “Cautor” Type (Single Arm)             

Depress the actuating arm fully, ensuring the bottom contacts make, releasing of arm should take between 6 to 8 seconds to return to its normal position. If adjustment is required the operating time can be altered by using the timing adjustment screw. The timing adjustment screw must not be removed from the dash pot.

Timing Adjustment – “Forfex” 

Depress fully and hold down actuating arm 1. Depress fully actuating arm 2. Release arm 2 and time the delay for it to return to its normal position. See figure 4.

The delay is the time for the arm to move between its bottom and top stops and must be determined visually. The delay should be between 6 to 10 seconds.

If adjustment is required the operating time can be altered by using the timing adjustment screw. Take care to adjust the correct screw i.e. the one furthest from the arm being adjusted.

Caution: Where adjustment of the timing is required the adjusting screw should be turned carefully and without undue force. Timing adjustment screws must not be removed from the dashpot nor tightened fully home.

Repeat the procedure for the other arm, depressing and holding arm 2 and then timing arm 1.

Depress both arms fully and release simultaneously. The time  between simultaneously releasing the arms and the point at which the control rod falls to the bottom of the V must also be within 6 to 10 seconds, regardless of the order in which the arms are lowered. If either of the values is lower (or higher) than the required value, turn the adjusting screw of the last arm lowered in (or out) as required (e.g. arm 2 adjustment screw for direction 1 to 2). If both values are lower (or higher) adjust both screws.