RAILWAY ELECTRIFICATION & POWER ENGINEERING
REPE Handbook: Introduction to Overhead Line Electrification RH11 August 2008 Version 4
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REPE Handbook RH11: Introduction to Overhead Line Electrification For Scott Wilson Railways Tricentre 3 Newbridge Square Swindon SN1 1BY and Scott Wilson Railways Buchanan House 58 Port Dundas Road Glasgow G4 0HG
Report Verification Name
Position
Prepared by:
Garry Keenor
Technical Manager (OLE)
Checked by:
Ian Moore
Section Manager (OLE)
Approved by:
Rob Tidbury
Head of Railway Electrification & Power Engineering
Signature
Date
Revision Schedule Version
Date
Details of Revision
Issued by
3
25 October 2004
Minor Revisions
GPK
4
15 August 2008
See details following page
GPK
Garry Keenor Technical Manager (OLE) Scott Wilson Railways Tricentre 3 Newbridge Square Swindon SN1 1BY Tel: Fax:
+44 (0) 1793 508870 +44 (0) 1793 508891
Email:
[email protected]
Significant Changes in this Revision
Section
Date
all
Converted to REPE handbook.
5.2
AC supply principles section expanded.
5.6
DC supply principles section expanded.
5.8
Protection section expanded.
6.2
Materials section added.
6.8
Turnout wiring section added.
6.11.7
Spanwire portal added.
This document has been prepared for use within Scott Wilson's Railway Electrification and Power Engineering (REPE) Unit. It is addressed to and for the sole use and reliance of Scott Wilson's REPE staff. Scott Wilson accepts no liability for any use of this document other than by REPE staff and only for the purposes, stated in the document, for which it was prepared and provided. No person other than REPE staff may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. © Scott Wilson Group PLC 2008
Railway Electrification & Power Engineering REPE Handbook: Introduction to Overhead Line Electrification
TABLE OF CONTENTS
1.
PURPOSE .........................................................................................................................16
2.
SCOPE ..............................................................................................................................16
3.
DEFINITION OF TERMS...................................................................................................16
4.
BASICS OF OLE...............................................................................................................16
4.1
What is OLE? ...................................................................................................................16
4.2
Unique Features of OLE..................................................................................................17
4.3
Advantages and Disadvantages of the System ............................................................18
4.4
RAMS ................................................................................................................................18
4.4.1
Reliability ...........................................................................................................................19
4.4.2
Availability..........................................................................................................................19
4.4.3
Maintainability ....................................................................................................................19
4.4.4
Safety.................................................................................................................................19
4.5
Development of OLE systems ........................................................................................19
4.5.1
Electric Beginnings ............................................................................................................20
4.5.2
Mainline DC Growth...........................................................................................................21
4.5.3
AC Developments..............................................................................................................22
4.5.4
High Speed Lines ..............................................................................................................23
4.5.5
UK Developments..............................................................................................................26
4.6
Categories of OLE System..............................................................................................29
4.6.1
Tram Systems....................................................................................................................29
4.6.2
Light Rail Systems .............................................................................................................29
4.6.3
Mainline Systems...............................................................................................................29 Page 5
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4.6.4
High Speed Systems .........................................................................................................29
5.
ELECTRICAL PRINCIPLES .............................................................................................31
5.1
Supply voltages and currents ........................................................................................31
5.1.1
Transmission and Supply Voltages ...................................................................................31
5.1.2
Supply Current...................................................................................................................32
5.2
AC Supply Principals ......................................................................................................33
5.3
AC Supply Equipment .....................................................................................................36
5.3.1
AC Transformers ...............................................................................................................36
5.3.2
Auxiliary Transformers.......................................................................................................36
5.3.3
AC Circuit Breakers ...........................................................................................................36
5.3.4
AC Cables..........................................................................................................................37
5.4
AC Sectioning Principles ................................................................................................37
5.5
AC Feeding and Immunisation Methods .......................................................................39
5.5.1
Classic feeding arrangement .............................................................................................39
5.5.2
Auto Transformer Feeding Arrangement ...........................................................................42
5.6
DC Supply Principals ......................................................................................................44
5.7
DC Sectioning Principles ................................................................................................44
5.8
Protection, Monitoring and Control ...............................................................................46
5.8.1
Fault Protection..................................................................................................................46
5.8.2
Control and Monitoring ......................................................................................................47
5.9
Electrical Clearances.......................................................................................................48
5.10
Earthing and Bonding .....................................................................................................50
5.10.1
AC Systems .......................................................................................................................53
5.10.2
DC Systems and Stray Currents........................................................................................53 Page 6
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5.10.3
Temporary Earthing Arrangements ...................................................................................53
5.10.4
Buffer Sections and Permanent Earths .............................................................................53
6.
MECHANICAL PRINCIPLES ............................................................................................55
6.1
Interface with the Pantograph ........................................................................................55
6.2
Materials ...........................................................................................................................59
6.3
Wire Types........................................................................................................................59
6.3.1
Contact Wire ......................................................................................................................59
6.3.2
Contact Bar........................................................................................................................61
6.3.3
Catenary Wire and Auxiliary Catenary...............................................................................61
6.3.4
Droppers ............................................................................................................................61
6.4
Insulators..........................................................................................................................62
6.4.1
Materials ............................................................................................................................62
6.4.2
Mechanical Requirements .................................................................................................63
6.5
Suspension Arrangements .............................................................................................66
6.6
Tensioning Arrangements ..............................................................................................69
6.7
Transferring the Pan between Tension Lengths ..........................................................70
6.7.1
Zero Span Overlap ............................................................................................................70
6.7.2
Single Span Overlap..........................................................................................................72
6.7.3
Multiple Span Overlaps......................................................................................................73
6.8
Turnout Wiring .................................................................................................................74
6.8.1
Low Speed Tangential Method ..........................................................................................74
6.8.2
Cross Contact Method .......................................................................................................74
6.8.3
Cross-Droppered Cross Contact Method ..........................................................................75
6.8.4
High Speed Tangential Method .........................................................................................76 Page 7
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6.8.5
High Speed Three Wire System ........................................................................................76
6.9
Other Electrical Break Devices.......................................................................................76
6.9.1
Section Insulator ................................................................................................................76
6.9.2
Neutral Sections ................................................................................................................78
6.10
Mechanical Clearances ...................................................................................................80
6.11
OLE structures.................................................................................................................80
6.11.1
Single Cantilever................................................................................................................82
6.11.2
Double Cantilever ..............................................................................................................83
6.11.3
Back to Back Cantilever.....................................................................................................84
6.11.4
Twin Track Cantilever ........................................................................................................85
6.11.5
Portals................................................................................................................................86
6.11.6
Headspans.........................................................................................................................87
6.11.7
Spanwire Portals................................................................................................................88
6.11.8
Bridge and Tunnel Supports ..............................................................................................88
6.11.9
Anchors..............................................................................................................................91
6.12
OLE Foundations.............................................................................................................94
6.12.1
Planted Mast Foundations .................................................................................................94
6.12.2
Side Bearing Concrete Foundations..................................................................................94
6.12.3
Mass Concrete Foundations..............................................................................................94
6.12.4
Piled Foundations ..............................................................................................................94
6.12.5
Gravity Foundations...........................................................................................................95
6.12.6
Rock Foundations..............................................................................................................96
6.12.7
Attachment to Other Infrastructure ....................................................................................96
6.12.8
Basic Design Ranges ........................................................................................................97 Page 8
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6.13
OLE Assemblies Overview .............................................................................................98
6.14
OLE Geometry................................................................................................................100
6.14.1
Vertical Limitations...........................................................................................................100
6.14.2
Horizontal Limitations ......................................................................................................102
6.14.3
Load Limitations...............................................................................................................105
7.
OLE DESIGN AND CONSTRUCTION PROCESSES ....................................................106
7.1
Process Overview..........................................................................................................106
7.2
Form EA and Form EB Processes ...............................................................................106
7.3
Design Documentation..................................................................................................106
7.3.1
Major Feeding Diagram ...................................................................................................107
7.3.2
Section Diagram and Switching Instructions ...................................................................108
7.3.3
Wire Run Diagram ...........................................................................................................109
7.3.4
OLE Layout Plan..............................................................................................................110
7.3.5
OLE Cross Section ..........................................................................................................111
7.3.6
OLE Bridge Drawing ........................................................................................................111
7.3.7
Bonding Plan ...................................................................................................................112
7.3.8
Dropper Tables ................................................................................................................112
7.3.9
Bill of Quantities...............................................................................................................113
7.3.10
Overhead System Design................................................................................................113
7.3.11
Testing & Commissioning Plan........................................................................................113
7.3.12
Operation & Maintenance Manuals .................................................................................113
7.4
Checking Process..........................................................................................................113
7.5
Design Licensing ...........................................................................................................114
7.6
Basic Design Ranges ....................................................................................................116 Page 9
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7.6.1
GE/MSW Range ..............................................................................................................117
7.7
Mark 1 Range .................................................................................................................118
7.7.1
OLEMI Range ..................................................................................................................119
7.7.2
UK1 Range ......................................................................................................................120
7.7.3
Auto Transformer Range .................................................................................................121
7.7.4
Other Assemblies ............................................................................................................121
7.8
Construction Methodology ...........................................................................................122
7.9
OLE Maintenance...........................................................................................................123
7.10
Types of UK Equipment ................................................................................................125
7.11
Interfaces with Other Subsystems...............................................................................125
7.11.1
Permanent Way ...............................................................................................................125
7.11.2
Civil & Structural ..............................................................................................................125
7.11.3
Signalling .........................................................................................................................125
7.11.4
Telecomms ......................................................................................................................125
7.11.5
Electrical & Mechanical Services.....................................................................................126
7.11.6
Operations .......................................................................................................................126
7.11.7
Highways .........................................................................................................................126
7.11.8
Environment.....................................................................................................................126
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Table of Figures Figure 1: A shortened TGV train takes the world rail speed record on 3 April 2007........................17 Figure 2: 6.7kV AC OLE on the London, Brighton and South Coast Railway; circa 1910...............20 Figure 3: The Sheffield – Manchester route via Wath, electrified with 1500V DC OLE...................21 Figure 4: 1500V DC at Gidea Park on the Great Eastern; this was converted, first to 6.25kV AC and then 25kV ..........................................................................................................................22 Figure 5: Mark 1 25kV AC, WCML, London Euston ........................................................................23 Figure 6: Track damage after 1955 high speed run; France ...........................................................24 Figure 7: 0 series Shinkansen; Japan .............................................................................................25 Figure 8: Extreme gradients on the TGV; Tonnerre, France ...........................................................25 Figure 9: APT tilting on neutral section tests; Murthat, WCML, UK .................................................27 Figure 10: Eurostar in preparation for record breaking run; Medway Viaduct, UK ..........................28 Figure 11: Typical feeding arrangements for AC OLE.....................................................................35 Figure 12: Sectioning arrangements for Perturbation Crossovers ..................................................38 Figure 14: Booster Transformer arrangement for OLE....................................................................41 Figure 16: Auto Transformer arrangement for OLE.........................................................................43 Figure 17: Typical feeding arrangements for DC OLE.....................................................................45 Figure 18: Detection of a fault .........................................................................................................46 Figure 19: ECR display screens; Melbourne, Australia ...................................................................47 Figure 20: Step potential .................................................................................................................50 Figure 21: Touch potential...............................................................................................................51 Figure 23: Principal of secondary insulation ....................................................................................53 Figure 24: Principal of permanent earthing and buffer sections ......................................................54 Figure 25: A pantograph on test; Old Dalby, UK .............................................................................55 Page 11
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Figure 26: Standard UK pan profile .................................................................................................56 Figure 27: Differential wind force on pantograph.............................................................................57 Figure 28: Typical Contact Wire Cross Section ...............................................................................59 Figure 29: Contact Wire Strength against Conductivity ...................................................................60 Figure 30: Overhead contact bar; Paris, France .............................................................................61 Figure 31: Lightweight shedded polymeric 25kV insulator; WCML, UK ..........................................62 Figure 32: Polymeric 25kV rod tension insulator; Stone, UK...........................................................63 Figure 33: 25kV shedded porcelain tension insulator formed of 3 cap & pin sections; Norton Bridge, UK ............................................................................................................................................63 Figure 34: 25kV shedded porcelain post insulator; WCML, UK.......................................................64 Figure 35: 25kV porcelain switching insulators with shed protectors; Norton Bridge, UK ...............64 Figure 36: Tramway OLE ................................................................................................................66 Figure 37: Stitched tramway OLE....................................................................................................66 Figure 38: Simple catenary OLE .....................................................................................................67 Figure 39: Presagged simple catenary OLE....................................................................................67 Figure 40: Stitched simple catenary OLE ........................................................................................68 Figure 41: Compound catenary OLE ...............................................................................................68 Figure 42: Fixed termination OLE....................................................................................................69 Figure 43: Auto tensioned OLE .......................................................................................................69 Figure 44: Uninsulated zero span overlap .......................................................................................70 Figure 45: Insulated zero span overlap ...........................................................................................71 Figure 46: Uninsulated single span overlap ....................................................................................72 Figure 47: Insulated single span overlap .........................................................................................72 Figure 48: Uninsulated three span overlap......................................................................................73
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Railway Electrification & Power Engineering REPE Handbook: Introduction to Overhead Line Electrification
Figure 49: Insulated three span overlap ..........................................................................................73 Figure 50: Low Speed Tangential Turnout Wiring ...........................................................................74 Figure 51: Cross contact turnout wiring...........................................................................................74 Figure 52: Cross contact arrangement ............................................................................................75 FFigure 51: Cross-Droppering Arrangement, Brinklow, UK.............................................................75 Figure 52: Discontinuous SI ............................................................................................................76 Figure 53: Continuous SI (plan view) ..............................................................................................77 Figure 54: High speed continuous SI; Rugby, UK ...........................................................................78 Figure 55: Principle of a neutral section ..........................................................................................78 Figure 56: APC magnets at a neutral section..................................................................................79 Figure 57: Arthur Flury type (left) and BICC glass bead type (right) neutral sections; Rugby, UK ..79 Figure 58: Typical single cantilever .................................................................................................82 Figure 59: Typical double cantilever ................................................................................................83 Figure 60: Typical back to back cantilever ......................................................................................84 Figure 61: Typical twin track cantilever ...........................................................................................85 Figure 62: Typical portal for four tracks with wideway .....................................................................86 Figure 63: Hinge-based portal leg on a viaduct, showing hinge pin ................................................86 Figure 64: Typical headspan for four tracks ....................................................................................87 Figure 65: Typical headspan for four tracks ....................................................................................88 Figure 66: Tunnel cantilever arrangement.......................................................................................89 Figure 67: Tunnel arm arrangement ................................................................................................89 Figure 68: Glass fibre bridge arm; Ripple Lane, UK ........................................................................90 Figure 69: Back-tied balance weight anchor with 3:1 anti-fall drumwheel and twin weight stacks; Newbold, UK ............................................................................................................................91
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Railway Electrification & Power Engineering REPE Handbook: Introduction to Overhead Line Electrification
Figure 70: MPA arrangement for cantilevers ...................................................................................92 Figure 71: Typical MPA arrangement for portals; Norton Bridge, UK..............................................92 Figure 72: Planted mast; WCML .....................................................................................................94 Figure 74: TTC with gravity pad; Aveley Marsh, UK........................................................................96 Figure 75: Pull-off single cantilever .................................................................................................98 Figure 76: Push-off single cantilever ...............................................................................................99 Figure 77: Height and stagger for OLE..........................................................................................100 Figure 78: Typical contact wire profile (y axis exaggerated)..........................................................101 Figure 79: Determining minimum stagger .....................................................................................102 Figure 80: MSO, blowoff, stagger effect and MTO ........................................................................103 Figure 81: Typical MFD detail........................................................................................................107 Figure 82: Typical section diagram detail ......................................................................................108 Figure 83: Typical wire run diagram detail.....................................................................................109 Figure 84: Typical layout plan detail ..............................................................................................110 Figure 85: Typical cross section detail ..........................................................................................111 Figure 86: Typical composite bonding plan detail .........................................................................112 Figure 87: Typical basic design drawing .......................................................................................116 Figure 88: GE OLE; Stratford, UK .................................................................................................117 Figure 89: Mark 1 portal; Norton Bridge, UK .................................................................................118 Figure 90: APT under Mark 3a headspans; Winwick Jct, WCML UK ............................................119 Figure 91: UK1 overlap portals; Millmeece, UK.............................................................................120 Figure 92: Auxiliary Feeder on CTRL section 1; Ashford, UK .......................................................121 Figure 93: OLE construction; Temple Mills, UK.............................................................................122 Figure 94: OLE Maintenance; Stafford, UK ...................................................................................123 Page 14
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1.
PURPOSE The purpose of this advisory note is to give an introduction to Overhead Line Electrification systems for railways. This document covers all types of railway and Overhead Line Equipment; all developments are covered, together with examples of UK systems.
2.
SCOPE This document applies to all OLE for tram systems, light or heavy rail, low speed or high speed. Discipline
3.
Applies?
Overhead Line Equipment (OLE)
9
Electric Traction Equipment (3rd/4th rail)
8
Mechanical & Electrical Systems
8
DEFINITION OF TERMS
Term
Definition
High speed
Speeds above 200kph
Heavy rail
Traditional railway systems; as opposed to light rail and tram systems
Overbridge
A bridge over the railway
Underbridge
A bridge under the railway
All other terms are defined in the body text.
4.
BASICS OF OLE
4.1
What is OLE? Overhead Line Equipment (OLE) is a system used to deliver continuous electrical energy to a stationary or moving train. It is also known in the UK as OHL or OHLE. In Europe & the US, it is known as Overhead Catenary System (OCS), and in New Zealand, as Overhead Wiring System (OWS). The generic term for the system is Overhead Contact Lines.
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This document will use OLE, as it is the preferred term in the UK. 4.2
Unique Features of OLE Unlike other power transmission systems, OLE is required to transmit high power (up to ~ 10MVA per train) to a load at a distance of several miles, which may be stationary or moving at up to 574kph1. The contact wire is therefore a twin system; it functions as both power transmission mechanism and sliding contact with the train.
Figure 1: A shortened TGV train takes the world rail speed record on 3 April 2007
The key requirement for any OLE system is to provide continuous power at the train. For this to happen there must be continuous contact between OLE and the pantograph (see section 6.1). Loss of contact leads to degradation of energy transfer and unwelcome damage to the contact wire and pantograph. OLE is a very exposed system, and is vulnerable to: • •
climate (especially wind, snow and ice); wildlife (particularly birds);
1
The current railway speed record is held by a French TGV unit, which reached 574.8kph on 3 April 2007 travelling under modified and super-tensioned (40kN) 31kV OLE. See http://en.wikipedia.org/wiki/TGV_world_speed_record for details.
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• •
pollution; vandalism.
It must be capable of withstanding frequent fault conditions without degradation of performance. The system tends to be constrained by other railway infrastructure, particularly in the UK where it has been retrofitted to railways dating from the 19th century, which were not built with OLE in mind. Due to the continuous contact requirements, the contact wire position is paramount. There is no redundancy in this part of the system; a second contact wire is economically and practically unsound. If contact wire strays outside position limits, the pantograph will usually damage a significant length of the OLE. OLE is therefore both an electrical and mechanical system, and the requirements of each must be balanced in the design. 4.3
Advantages and Disadvantages of the System The key advantages of OLE systems over train-borne traction (e.g. diesel, gas turbine) can be summarised as: • • • • • • •
Flexibility of energy source; Reduced emissions; Concentration of emissions at single source; Lower energy usage through regenerative braking; Lower rolling stock maintenance costs; Greater reliability leading to smaller fleet requirements; Reduced noise.
Additionally, OLE has the advantage over conductor rail transmission system at high speeds; the conductor rail is limited by current collection requirements to about 160kph with current technology. Set against this are the disadvantages of the system: • • • •
High capital cost of installation; Lack of redundancy in contact wire; Management of safety risks from high voltages; System is vulnerable if badly designed.
Because of the high capital cost of OLE, it has historically been difficult to gain funding for new electrification schemes; especially in the UK. Therefore the OLE designer should at all stages seek to minimise the installation costs, while balancing this against the Reliability, Availability, Maintainability and Safety (RAMS) criteria for the system. 4.4
RAMS RAMS analysis is a technique used to optimise the performance of a system. The ideal is to reach, but not exceed, the required levels of Reliability, Availability, Maintainability and Safety
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using the most cost-effective means over the life of the system – the lifecycle. This takes into account not only the capital cost of the system installation, but the maintenance and operation costs over the lifecycle. 4.4.1
Reliability It is essential that an OLE system be reliable, as measured in mean time between failures. The reliability should be set at a level that is the same, or better than, the other railway systems at that location. Reliability is especially important for OLE, as it is critical for electric train service. For instance, financial constraints at the time of the East Coast Mainline (ECML) electrification mean that both the electrical supply and the mechanical support arrangements are less reliable than the other systems. The ECML is subject to frequent and serious service delays due to traction supply failure, and this can lead to a reduction in the credibility of electric traction systems in general – particularly in the eyes of those financing the system.
4.4.2
Availability Availability is a measure of the amount of time the system has to be taken out of service for routine maintenance. Poor design leads to more frequent maintenance requirements, and lower availability. For instance, poor choice of contact wire material can lead to increased wear; this in turn means the wire must be replaced more frequently, necessitating longer periods out of service.
4.4.3
Maintainability OLE is an exposed system and is subject to wear and damage from a variety of causes. It is essential that the ability to access the equipment for maintenance is built into the design. High maintenance items should be readily accessible. For instance, manually-operated switching sites should be placed near access points, and configured to cause minimum disruption to services.
4.4.4
Safety The electrical and mechanical energy contained within OLE can cause serious injury and death if not controlled. It is the designer’s role under the Construction Design & Management (CDM or CONDAM) regulations, to ensure that safe construction, operation, maintenance and decommissioning of the system is fully integrated with the design. While it is impossible to achieve absolute safety, the risks inherent in the system must be analysed, and any unacceptable risk reduced to an acceptable level. For instance, placing live OLE adjacent to a school playground fence creates an unacceptable risk. The addition of a suitable screen at this location reduces the risk to a degree known as ALARP (As Low As Reasonably Practicable).
4.5
Development of OLE systems The following sections give an overview of the history of OLE development. For a more detailed list of UK builds, see APPENDIX III.
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4.5.1
Electric Beginnings The first OLE systems were used with passenger trams in the last years of the 19th century. These generally consisted of a simple single wire (trolley) system, suspended from poles and buildings, and fed at a low voltage. This was preferred to the previous 3rd rail systems, which had safety implications for on-street running. The first thirty years of the 20th century saw these principles extended to mainline systems as the advantages of OLE over 3rd rail became clear. Due to the increasing distances covered and the I2R losses encountered, voltages were increased. At the same time, more sophisticated suspension systems were required to maintain good current collection at increasing linespeeds.
Figure 2: 6.7kV AC OLE on the London, Brighton and South Coast Railway; circa 1910
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Railway Electrification & Power Engineering REPE Handbook: Introduction to Overhead Line Electrification
Experimental AC schemes were implemented for Lancaster to Heysham (1908) and London Victoria to London Bridge (1909) schemes, both at 6.7kV, 25Hz AC. AC motor technology was not developed at this time, necessitating complex train-borne rectification equipment; this was not yet reliable, so AC did not make any further headway until after World War Two. On Tyneside, the Newport – Shildon line, which featured heavy coal trains running over steep gradients, was electrified with 1500V DC OLE in 1915. 4.5.2
Mainline DC Growth The problems with AC, coupled with the transmission limitations of DC current, meant OLE was only used for suburban and freight systems; heavy electrical loads and short distances meant DC OLE made economic sense. In the UK, 1500V DC OLE was agreed in the 1930s as the national standard. The Sheffield to Manchester (via Wath) route, which required very heavy coal trains to be hauled over the steep gradients of the Derbyshire peaks, was authorised for electrification in 1939. However World War Two brought this (and all other electrification schemes in Europe) to an abrupt halt. These recommenced after the war, but at a much reduced rate; the railways’ priority was rebuilding their battered infrastructure rather than funding new schemes. The Wath scheme was eventually completed in 1952: this turned out to be a pyrrhic victory, as within 6 years the DC standard was obsolete. The line survived until 1981, by which time it was an isolated system.
Figure 3: The Sheffield – Manchester route via Wath, electrified with 1500V DC OLE
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Railway Electrification & Power Engineering REPE Handbook: Introduction to Overhead Line Electrification
Unlike the UK, where overhead electrification proceeded only falteringly, the rest of Europe installed a large amount of 1500V DC in the pre- and post-war years, and much of this network still exists. 4.5.3
AC Developments The 1950s saw increased interest in AC OLE; this was driven by the emergence of reliable industrial frequency AC technologies in the electricity supply industry. This meant that high voltage, long-distance AC transmission – and by inference, inter-city OLE systems – was now feasible. Across Europe, the 1500V DC standard was dropped in favour of 25kV at 50Hz AC; in the UK this was approved as the standard for future schemes in 19562. The Lancaster to Heysham route, which had pioneered HV AC OLE in 1908, was converted from 25Hz to 50Hz in 1951 to serve as a test bed for industrial frequency supply. These tests confirmed the choice as the right one. A test scheme was installed between Colchester and Clacton in 1959. Various types of OLE were trialled, including simple and stitched, but compound was chosen as giving the best current collection at speed3. It was initially assumed that 25kV AC systems would require substantial electrical clearances to existing infrastructure; in particular, it was felt that 275mm clearance would be required for bridges. In the UK this would not be possible without reconstruction work, particularly for many bridges in the vicinity of large stations. For these areas a reduced voltage of 6.25kV was proposed; trains would be dual-voltage and switch between them on the move as necessary.
Figure 4: 1500V DC at Gidea Park on the Great Eastern; this was converted, first to 6.25kV AC and then 25kV
2 3
Electric Railways, 1880 – 1990, Michael C Duffy, The Institution of Electrical Engineers, 2003, p321 Paper; A D Suddards, T H Rosbotham, T B Bamford
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Experience on the lines out of Liverpool St, where the 1500V DC lines were converted to 6.25kV AC, showed that there was excessive caution in the standard clearances. Reduced and Special Reduced clearances were added (see section 5.9), so that 25kV could be adopted throughout. The West Coast Mainline (WCML) electrification was the first large scale 25kV scheme in the UK; it was first proposed with 6.25kV sections, but was implemented fully at 25kV. The dual voltage locomotives which had been built for the route were modified as single voltage machines4. The existing 6.25kV areas were then converted to 25kV throughout. The first phase of the West Coast scheme was extremely successful in operational terms; it brought about a step change in service speed, and revived an image of high speed rail travel last seen in the 1930s; this came to be known as the “sparks effect”. In Engineering and financial terms, however, the scheme was less successful. The project ran over budget, and when British Rail (BR) proposed a rolling programme of mainline electrification schemes, the Ministry of Transport made it clear that costs would have to come down. BR responded with a wholesale overhaul in the design systems for OLE. The heavy, bespoke portal arrangements of the West Coast equipment were shelved, in favour of a new, lightweight, modularised, headspan-based metric system (the Overhead Line Equipment Master Index, or OLEMI – see section 7.7.1). This system, initially known as Mark 3, was further developed as Mark 3a; in this form it was used on the second phase of West Coast from Weaver Junction through to Glasgow in 1974.
Figure 5: Mark 1 25kV AC, WCML, London Euston
4.5.4
High Speed Lines
4
Electric Railways, 1880 – 1990, Michael C Duffy, The Institution of Electrical Engineers, 2003, p323
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Elsewhere in Europe, the possibilities for higher speed passenger trains using electric traction began to be explored. The French state railway, SNCF, began a series of experimental runs in the 1950s, culminating in a recordbreaking run reaching 326kph in March 1955. This used a modified 1500V DC system, with the line voltage increased to 1900V by means of mobile substations5. The record stood until 1981. The tests showed the obstacles to be overcome if speeds over 300kph were to become the norm. Frictional heat caused the pantographs to collapse; track damage was so great that derailment was only narrowly avoided.
Figure 6: Track damage after 1955 high speed run; France
5
“Electric Railways: 1880 – 1990”; Michael C Duffy; The Institution of Electrical Engineers; p389
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Japan was the first country to build an electrified mainline railway from scratch. The Tokyo - Osaka Shinkansen ('New Trunk Line') opened in 1964. This was segregated from existing lines, and used 25kV 60Hz AC OLE rather than the 1500V DC used elsewhere in Japan. The line had no level crossings and was designed for continuous high speed with linespeeds of up to 210kph. Following the success of this build, the Shinkansen network has spread, with higher speeds being attained – the latest trains run at 300kph.
Figure 7: 0 series Shinkansen; Japan
France continued to develop their high speed system, and the Train á Grande Vitesse (TGV) concept was born. This would use dedicated high speed lines, high powered trains and a 50kV ATx system (see section 3.4). Gradient profiles would be steep, since the high power available meant that expensive civil engineering works would be minimised.
Figure 8: Extreme gradients on the TGV; Tonnerre, France
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The first TGV line between Paris and Lyon (TGV Sud-Est) opened in 1981. Since then, additional lines have been opened, and the TGV concept has been exported to Germany (as the ICE), the US (the Acela) and the UK (the Channel Tunnel Rail Link). 4.5.5
UK Developments In the UK, the oil crisis and recession of the 1970s brought a further squeeze for railway finances. Having completed the West Coast in 1974, BR had intended to electrify the Great Western (GW) mainline between London and Bristol. However, finance was not forthcoming and so BR turned to the High Speed Train (HST) concept. This pushed diesel traction design to the limit to produce a 200kph fixed length diesel train capable of sustained high speed running. The HST held the world speed record for a diesel train, reaching 232kph on 12 June 1973; this was not surpassed until 2002. The project was so successful that the HST build was extended to provide higher speeds on the East Coast Mainline (ECML) and Midland Mainline (MML). This effectively stalled the mainline electrification program – in the case of ECML, by 10 years; MML is yet to be fully electrified. Despite the success of HST, it was recognised that diesel technology had reached its limit, and that for higher speeds, OLE traction was needed. Furthermore, the financial squeeze meant that these speeds would have to be attained on existing infrastructure. This led to the development of the Advanced Passenger Train (APT) – the world’s first tilting train. By using tilt, the train was able to achieve speeds of up to 255kph on the existing curves of the WCML.
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Figure 9: APT tilting on neutral section tests; Murthat, WCML, UK
The APT used a number of novel technologies in addition to tilt. Articulated bogies were used, where carriage ends sat on a single bogie, thus improving ride quality. Two stage hydraulic/air brakes were used to improve braking performance. The pantograph was linked by chains to the bogie, thus countering the tilt of the train body. On 20 December 1979 an APT took the UK speed record from HST, reaching 259 kph. The complexity of the train proved to be its undoing. Major teething problems were encountered when the train entered service in 1981, and this was compounded by some ill-advised press runs leading to bad publicity, and the worst weather seen in years that winter. By 1984 BR were on the point of solving the technical problems, but political backing for the project had evaporated and funding was stopped. APT was ultimately a failure of political will rather than technology. The lessons learned were taken by Italian train builders, who developed the Pendelino concept, successfully used throughout Europe – and now, ironically, sold back to the UK as the West Coast Pendelino. Electrification proceeded in the UK through the 1980s, albeit on smaller schemes such as St Pancras – Bedford and Colchester – Ipswich. BR was finally given the go-ahead in the mid 1980s to electrify the ECML, and this was completed in 1991. However, budgetary constraints meant the OLE on this scheme was under-powered and prone to dewirement under extreme windspeeds.
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Infill schemes continued in the 1990s, with Cambridge to King’s Lynn, Carstairs to Edinburgh and London to Heathrow Airport all completed. A significant milestone was the opening of the Channel Tunnel, operating at 160kph with OLE. However privatisation has broken the link between infrastructure capital cost and train maintenance cost which was vital to justify the initial cost electrification schemes. The splitting of rolling stock procurement, rolling stock operation and infrastructure ownership led to a huge increase in diesel procurement, as no party would benefit from the whole life advantages of electric traction. By the early years of the 21st century the only major schemes in progress were the West Coast upgrade, and the Channel Tunnel Rail Link (CTRL), which finally brought true high speed (300kph) running to the UK. Section 1 of CTRL opened in 2003, and section 2 into London was opened in 2007. On 30 July 2003, a Eurostar test train took the UK rail speed record from the APT, reaching 334.7kph (208mph) on section 1 of CTRL.
Figure 10: Eurostar in preparation for record breaking run; Medway Viaduct, UK
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4.6
Categories of OLE System The parameters of the OLE must be matched to the system to which it is to be applied. OLE systems may fall into one of four broad categories.
4.6.1
Tram Systems Trams are mass transit systems, used to move large volumes of people over relatively short distances at relatively low speeds (up to 80kph), usually in and out of urban centres. These systems feature on-street running, tight radius curves, steep gradients, short headways between trams and line of sight driving (i.e. no signalling except at highways interfaces). They are usually of post-war vintage. Tram OLE system design is driven by the need to ensure the safety of the public, and by the many interfaces with buildings and highways. The systems are low voltage (usually 750V DC) and are often split into on-street and off-street equipments; the former being characterised by high contact wire, fixed termination tramway (see 6.5) and support from buildings, and the latter by a more conventional system with catenary and auto-tensioning. Support assemblies are very light, and secondary insulation is used to prevent stray currents (see 5.10.2) from entering buried services.
4.6.2
Light Rail Systems Light rail systems are a step up from trams. They are also mass transit systems, situated in and around urban centres, but they do not feature on-street running, and share many of the characteristics of heavy rail, such as fixed signalling. Speeds are usually below 120kph. For these systems, supply voltages are higher (often 1.5kV DC), and the OLE is often fixed termination, with simple catenary (see section 6.5). Structures and assemblies are lightweight, and headspans (see section 0) are often used. The Tyne & Wear Metro is an example of such a system.
4.6.3
Mainline Systems Mainline systems form the bulk of the OLE railway route mileage worldwide. These systems are mainstream traditional railways; speeds may be anywhere up to 200kph, and traffic may be heavy and frequent, with a mix of passenger and freight. The railway may date from Victorian times, the OLE having been superimposed at a later date. Standard supply voltages are 1.5kV and 3kV DC, and 25kV 50Hz AC (standard for all systems since the 1960s). OLE is either simple or compound; assemblies are heavier, and portal (see section 6.11.5) or headspan structures may be used.
4.6.4
High Speed Systems Mixing passenger services – at speeds above 200kph – with slower moving freight is not practical or safe. For this reason, high speed systems are usually dedicated to passenger services; the high power available often means steep gradients are used, reducing construction costs. These lines are usually less than 40 years old, and built with OLE standard clearances.
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The standard supply voltage is 25kV 50Hz AC, usually with a transmission voltage of 50kV and an Auto-Transformer system (see section 5.5.2). Good current collection becomes paramount; OLE is either sagged simple (see section 6.5), stitched simple or compound. Assemblies are lightweight; structures are a mix of portals and cantilevers (see section 6.11).
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5.
ELECTRICAL PRINCIPLES
5.1
Supply voltages and currents
5.1.1
Transmission and Supply Voltages Transmission Voltage is the voltage at which energy is transmitted to the train’s location. Supply Voltage is the voltage at which the train is supplied with energy. For the majority of systems, the transmission and supply voltages are equal. However, some high speed lines use a higher transmission voltage to avoid excessive heat losses and thus provide more power at the train. A variety of supply voltages are used around the world, due to a combination of historical and operational factors. 750V DC is the de facto standard for tram systems, and is chosen to minimise safety issues in public areas. 25kV 50Hz AC is used for the majority of new mainline and all new high-speed builds. Most countries (with the notable exception of the UK) have a legacy network of 1500V DC. It should be noted that the supply voltage is not a single constant value; I2R losses, magnitude of load in section and other factors affect the supply voltage at the train. For instance, below are the allowable voltages for UK 25kV AC systems6; System Voltage
Description
25 kV
Nominal system voltage
29 kV
Train equipment should be able to operate without suffering damage if the voltage rises to this level for 5 minutes
27.5 kV
Maximum voltage at which train equipment should operate continuously
24 kV
Average voltage for use in train performance calculations
20 kV
Minimum constant current voltage value
16.5 kV
Minimum voltage in normal operation. If the voltage falls below this value it should not be possible to initiate regenerative braking
14 kV
Minimum voltage at which a train should continue to operate for not more than ten minutes without being damaged. Also the voltage below which regenerative braking should cease.
6
RT/E/C/27010 “Compatibility Between Electric Trains and Electrification Systems”, Issue 1, November 1997, Para. 2.2
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System Voltage
Description
12.5 kV
Minimum voltage at which a train should continue to operate for not more than two minutes without being damaged. Equipment energised from the overhead line need not continue to operate if the voltage falls below 12.5kV, but should not be damaged.
Each system will have a line voltage performance specification in this way; the OLE system design is tailored to meet this. 5.1.2
Supply Current The supply current is obviously dependent upon the train power characteristic and the number of trains in section at any one time. For Low Voltage (LV) DC systems, the supply current is relatively high; Train Type
Train Current Draw
750V DC three car tram
~ 1100A
750V DC train
~ 3000A
1500V DC train
~ 1500A
For AC system, the higher voltage available means lower supply currents; Train Type
Train Current Draw
25kV AC passenger train
~ 200A
25kV double headed freight train
~ 500A
Of paramount importance is the maximum fault current, that is, the maximum current which will flow under fault conditions. The entire OLE system must be designed to withstand many such faults over the lifetime of the equipment, without degradation of the components. For UK 25kV systems, the maximum fault current is 6kA: for some high current systems, an increased level of 12kA is proposed.
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5.2
AC Supply Principles DC systems have historically been constrained to lower supply voltages (up to 3kV) due to the expense and availability of rectification equipment. Since AC systems do not require rectification equipment, they can use higher voltages than DC. This leads to much lower volt drop, and so feeder stations can be further apart than for DC systems – for a standard 25kV feeding system, feeder stations are 40 to 60km apart. This eliminates the requirement for a separate HV feeding network. Supplies have traditionally been obtained at each feeder station from the 132kV Distribution Network Operator (DNO - also known as a Regional Electricity Company or REC). 25kV is obtained through 132/25kV transformers supplied by the DNO. These are often duplicated to give supply security or redundancy. These transformers are usually procured by the railway but owned and maintained by the DNO. They may be sited at a DNO compound alongside the railway feeder station, or sited at a remote DNO site with 25kV cabling between the two. More recent installations take their supplies from the 400kV Electricity Supply Industry (ESI – also known as National Grid Company or NGC) system to limit load imbalance (see below). The single phase supply taken from the 3 phase system at each feeder station creates an unbalanced load (or phase imbalance) on the supply authority’s system. The supply authority has contractually agreed limits with its customers on the total imbalance. The railway can often be the biggest single contributor to this imbalance. Therefore the supply authority will generally impose an overall limit for the railway contribution to the imbalance. UK limits are 1.5% on the grid or DNO; and 0.5% contribution by the railway. To help limit the imbalance, adjacent feeder stations use different phase combinations; e.g. feeder 1 uses red-blue, feeder 2 uses blue-yellow, feeder 3 uses yellow-red. Direct connection of these adjacent systems is prohibited for electrical reasons, so a short section of dead OLE – a neutral section – is used to keep the phases apart. Trains shut off power before the neutral section, usually by means of an automatic trip, and coast through the neutral section before the power is tripped on again (see section 6.9.2). The OLE between feeder stations is electrically split into sections and subsections to allow for emergency feeding and maintenance. Each running line is electrically separate from the others. Sectioning is maintained at intermediate locations called Track Sectioning Cabins (TSCs). These are the equivalent of the Track Paralleling Hut (TPH) on a DC railway. The midpoint TSC – so called because it is midway between feeder stations – carries a neutral section which keeps the phases at adjacent feeder stations apart. Each feeder station also has a neutral section. This means that the phase split may be moved up and down the railway in emergency feeding conditions. A typical sectioning arrangement is shown overleaf. Typical spacings for 25kV classic feeding are: • • •
Feeder Station to Feeder Station – from 40 to 60 km; Feeder Station to midpoint TSC - approx 24km; Feeder Station to TSC - approx 11km.
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Spacings are determined by the traffic to be handled, the train performance requirements and the electrical characteristics of the overhead and supply systems. Such considerations result in an optimum spacing which it is not often possible to achieve, and shorter sections are often used to locate the feeder stations at strategic points such as junctions or route intersections. Feeder Stations are usually situated in close proximity to grid substations in order to avoid the disadvantages of long feeders.
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Figure 11: Typical feeding arrangements for AC OLE
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5.3
AC Supply Equipment
5.3.1
AC Transformers AC transformers are used to step voltages down from 132kV or 400kV to the supply voltage. They are typically of a conventional oil-filled naturally-cooled design. Off load tap changing of ±2½ and 5 percent is normally provided to allow the output voltage to be adjusted, but transformers with remotely controlled on-load tap changing are sometimes installed to allow this adjustment to be made in service. Transformers are generally supplied in standardised sizes: • • • •
15 MVA/600A; 10 MVA/400A; 7½ MVA300A; 5 MVA/200A.
Where AC supplies are derived from networks operating at voltages lower than 66kV, (e.g. 33kV or 11kV) the transformers are usually purchased by the railway infrastructure owner. 5.3.2
Auxiliary Transformers Auxiliary supplies are often taken from the OLE at a Feeder Station or TSC, either to supply local Low Voltage (LV) equipment or as a backup to other supplies. Auxiliary supplies can be for: • • • • •
Signalling Supplies (typically 650V or 400V); Battery charging (typically 110V); Operation of switchgear; Lighting; Heating.
These supplies are derived from the traction supply by means of step down transformers. 5.3.3
AC Circuit Breakers Circuit Breakers are designed to allow the supply to be interrupted during fault conditions or for routine maintenance. They must be capable of closing and opening (making and breaking) both the normal operational currents (load current) and the much higher currents experienced during a fault (fault current). They must be able to do this many times over their life without experiencing degradation of the contacts. Of particular importance is the ability to quickly extinguish the arc which forms as the electrical contacts move apart. AC circuit breaker technology has advanced significantly in the last 50 years, and this is reflected in the range of circuit breaker types on the railway. In historical order of installation, they are: • • • •
Oil insulated; Air insulated; Vacuum insulated; Sulphur Hexafluoride (SF6) insulated.
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Oil Circuit Breakers (OCBs) were used for installations until the 1970s. Oil provides a good electrical insulator and will extinguish the arc quickly while dissipating the heat generated. However, they are heavy and bulky, and are not able to clear faults quickly, while repeated operations contaminate the oil with carbon deposits which further degrade performance, meaning regular maintenance is required. Vacuum Circuit Breakers (VCBs) were first used in the 1970s. Their simplified mechanical arrangement means they were thought to be more reliable than OCBs, giving improved interrupting capacity, increased contact life, and requiring less maintenance. They are also significantly quieter and smaller than OCBs. Sulphur Hexafluoride (SF6) breakers were introduced because the vacuum in VCBs was proving hard to maintain. Initially SF6 was used for both insulation and arc-breaking purposes, but it was found that under arcing conditions the gas breaks down into acidic elements which damage the breaker. More recent SF6 designs have used the gas for insulation only, with a vacuum used for extinguishing the arc. However SF6 is extremely environmentally damaging and the search is on for a suitable replacement. Recent developments have looked at the use of resin, or even a modern form of the oil-filled circuit breaker. 5.3.4
AC Cables Incoming supplies from the DNO are typically delivered to the railway feeder stations through 400-500mm2 two-core concentric pressure cables. The same type of cable is also used where connections are required between railway feeder stations. Generally the cables are of the oilfilled type, with some being gas-filled. This latter type has the advantage of a lower charging current, and is favoured for tunnel use. Connections from the switchgear to the 25kV overhead contact system are usually formed of 25kV single core solid type cables.
5.4
AC Sectioning Principles OLE systems are generally divided into electrical sections, allowing sections of OLE to be isolated during planned maintenance or emergency situations. Sectioning is carefully chosen to give the ability to isolate any OLE section, while keeping the resultant train diversion around the isolation as short as possible. Crossovers are provided, typically every 3½ - 5 miles, to allow trains to transfer from the normal running line to the wrong direction line under perturbation conditions. Subsections bridged by isolators are provided to allow the OLE to be isolated at a fault. The train then runs wrong direction around the isolated subsection. Isolators have traditionally been manual, requiring switching on site, but remote-operated motorised isolators are increasingly used.
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Figure 12: Sectioning arrangements for Perturbation Crossovers
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5.5
AC Feeding and Immunisation Methods
5.5.1
Classic feeding arrangement The first OLE systems used the OLE to transmit power to the train, and one or more running rails to return current to the supply point. In AC systems this was found to be unsatisfactory, due to the large electromagnetic (EM) field created around the OLE. This induces a voltage in any LV cables in the vicinity of the OLE, and is a particular problem for safety-critical signalling cables. A partial solution was found with the introduction of the Return Conductor (RC) system. The RC is a conductor which runs parallel to the OLE, at approximately the same height, and positioned on the lineside. The RC is bonded at regular intervals to the running rail, and provides a measure of current sharing. Because the current flows in the opposite direction to that in the OLE, and it at equal height, the two EM fields tend to cancel at ground level. However, the fields are not equal, and there is still the potential for interference. The answer lay in transferring all the return current from the rail to the RC. This was achieved by means of Booster Transformers (BTs). A BT is a 1:1 ratio transformer; the primary is connected across the OLE in such a way that traction current is forced through it. The secondary is connected across a break in the RC. The current in the primary induces an equal and opposite current in the RC; this current is drawn from the rail at a bond connection midway between BTs called the midpoint connection (MPC). Figure 13: Booster transformers; Whitmore, UK
This system ensures that all return current moves from rail to RC and so provides a large measure of signalling immunisation. Booster Transformers are located every 3 miles, and OLE overlaps are used as a convenient point for a break in the OLE. For this reason signals should not be located near to Booster Transformers, as there is a risk of OLE burnout when a pantograph comes to a stand shorting out the BT (see section 6.7.2).
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the traction system. It has been used widely across Europe and in the UK, but there remain a large number of legacy RC only routes. The BT arrangement is shown overleaf.
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Figure 14: Booster Transformer arrangement for OLE
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5.5.2
Auto Transformer Feeding Arrangement There are practical limits to the amount of power that a BT system can deliver; I2R losses increase, and there is a limit to the amount of OLE cross section which can be provided without driving wire tensions to impractical values. In particular, the drive for higher speeds led to the requirement for a system with much higher power availability. The Auto Transformer (ATx) system was pioneered first at Philadelphia in the US in the early 20th century, using 36kV transmission and 12kV supply. It was then used on the Shinkansen at 60kV:30kV, before being introduced in Europe for TGV routes at 50kV:25kV. This is now the favoured ratio for new high speed lines, and the detail below is based on this. The ATx system is a 50kV AC transmission system, which is why higher power levels are available. Since power is proportional to V2, there is more power available in the classic feeding system. Alternatively, the same power can be delivered with fewer feeder stations spaced further apart. The heart of the system is the ATx itself. This is a 1:1 ratio 25kV-0V25kV centre-tapped transformer, with the OLE is fed from one half of the winding at +25kV, and an Auxiliary Feeder (AF) fed from the Figure 15: Simplified AT Feeding other half at -25kV (actually antiphase to the OLE). The running rail is connected to the 0V centre tap. The AF carries out the same immunisation role as a return conductor, which is not required in an ATx system. Delivery to the train is at 25kV as normal – a key requirement of any 50kV system, which must interface with traditional systems and trains. Approximately half the train current comes directly from the feeder station via the OLE; the other half comes from current induced in the OLE by the –25kV half of the ATxs. The additional 25kV AF conductors create additional design challenges; 25kV clearances must be maintained for AF to earth, but also 50kV clearances for AF to OLE. This can be a particular problem through limited clearance overbridges and stations. The ATx system is widely used on European high speed systems, and in the UK it is installed on the CTRL and is being piloted on WCML to overcome the problem of a saturated classic feeding system. The ATx arrangement is shown overleaf.
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Figure 16: Auto Transformer arrangement for OLE
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5.6
DC Supply Principles For the historical reasons outlined in section 5.2 DC overhead transmission is generally at lower voltages (3kV or lower). This means the system suffers from a large volt drop as a percentage of the supply voltage, and substations must be placed close together (typically 4km apart). The cost of providing a direct feed from the DNO at each location would be prohibitive, so DC railways usually have a dedicated HV trackside feeder system to provide power to the substations. These rings are typically at 66, 33, 22 or 11kV, fed from a 132kV grid infeed. The HV supply is then transformed down and rectified at each substation to provide power to the railway. The rectifier is fed with all 3 phases, meaning there is no imbalance on the DNO supply or requirement for neutral sections.
5.7
DC Sectioning Principles Switching is carried out at intermediate Track Paralleling Hut locations. These help keep the system impedance down by paralleling all tracks together. A typical sectioning arrangement is shown overleaf.
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Figure 17: Typical feeding arrangements for DC OLE
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5.8
Protection, Monitoring and Control
5.8.1
Fault Protection OLE systems are vulnerable to a large number of faults. These faults can cause currents to flow that are much larger than those caused by normal operation; these would cause considerable damage if allowed to flow unchecked. To prevent this damage a protection system is used to clear faults by opening the circuit breakers feeding into the section. Any system of protection must: • • •
Be sufficiently sensitive to detect a fault in its early stages; Be absolutely reliable in operation – the simpler and most robust the design the better; Discriminate between currents fed to faults within the section being protected and current passing through to a fault in another section.
OLE is split into sections that are fed from one (AC) or both (DC) ends. Each feed is routed through a circuit breaker. Attached to this by means of a current transformer (CT) and Voltage Transformer (VT) is a relay which looks continuously for faults, by measuring the impedance of the section that it is feeding. This is known as impedance or distance protection. Fault current will usually flow through several circuit breakers between the fault and the feeder station. This gives the opportunity to provide time delayed backup protection. For instance, UK heavy rail OLE has three zones of protection: zone 1 is instantaneous and is set to the impedance of the initial section less a calculation tolerance; zone 2 sees approximately 70% of the next section and has a small time delay; and zone 3 sees all of the next section with a larger time delay. Consider a system consisting of three series sections, each protected separately and capable of isolation by a circuit breaker at the feeding end:
Figure 18: Detection of a fault
The fault at F is a section fault relative to Section C, but a through fault relative to Sections A and B. Thus the protective devices on Sections A and B should not trip their respective circuit breakers, whilst the protection on Section C should open its circuit breaker.
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If circuit breaker C does not clear the fault within the specified time, then the protection on section B will cause circuit breaker B to trip. Similarly, circuit breaker C will act if circuit breaker B does not. In addition to impedance protection, overcurrent and under-voltage protection may be provided. These systems will protect the OLE against overload and trains against undervolts respectively. 5.8.2
Control and Monitoring The circuit breakers at feeder stations and TSCs are under the control of the Electrical Control Room (ECR). This is a central control centre which supervises operation and maintenance of the OLE. A telecommunication system known as Supervisory Control and Data Acquisition (SCADA) is used to monitor and control circuit breakers remotely. The SCADA system polls each feeder station in turn, interrogating the state of each circuit breaker. Any change in state or alarm is relayed back to the ECR. Similarly the ECR can send an instruction to a particular circuit breaker to open or close in the event of a fault or maintenance. The ECR Operator (ECRO) is able to monitor and control the whole system from a set of display screens at a central terminal. Motorised switches under ECRO control may also be provided at key locations if fast perturbation management is required.
Figure 19: ECR display screens; Melbourne, Australia
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5.9
Electrical Clearances It is essential for safety and reliable operation to keep all live parts of OLE a sufficient distance from other infrastructure, so that flashover is prevented. For this reason two sets of clearances are defined. The static electrical clearance is the clearance which must be achieved under static conditions. The passing electrical clearance is the clearance which must be maintained for a short duration as the train passes. These clearances are set for a particular system voltage. It is usual to have more than one level for each clearance in recognition of the different circumstances which may apply. For instance, UK 25kV AC standards7 define four levels of clearance which may be allowed; • • • •
Enhanced Clearances should be used wherever possible; Normal Clearances should be used where enhanced clearances cannot be attained; Reduced Clearances can only be used with the consent of the infrastructure owner when normal clearances cannot be attained; Special Reduced Clearances can only be used with the consent of the safety authority when reduced clearances cannot be attained.
Enhanced
Normal
Reduced
Special Reduced
Static
≥ 600mm
270 – 599mm
269 – 200mm
199 – 150mm
Passing
≥ 600mm
≥ 200mm
199 – 150mm
149 – 125mm
Where enhanced clearances cannot be provided, such as at low overbridges, a section of contact wire replaces the catenary. This minimises the chance of wire stranding in the event of a flashover. This cable is known as contenary. In addition to electrical clearances, minimum safety clearances must be maintained to those areas accessible to public and staff. These safety clearances are considerably more onerous than the equivalent electrical clearances a given system. For instance, the normal minimum safety clearance for 25kV AC lines is 2.75 metres. It is only possible to reduce this clearance if some form of protective barrier or screen is provided. It should be noted that the term “live parts” includes the pan itself. Due to the position and width of the pan, this can often be the most extreme part of the live envelope; it is important to
7
GE/RT8025 “Electrical Provisions for Electrified Lines”; Railway Safety & Standards Board; Para. B4.6.2
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consider this in the design of signals and other infrastructure which have maintenance access platforms.
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5.10
Earthing and Bonding Traction earthing and bonding is the term used to describe the arrangements for ensuring a low impedance return path for traction current and fault current. The system is designed to: • • • •
Provide a low impedance path for return current; Allow faults to be detected and cleared quickly; Keep the rail potential within limits; Eliminate touch potentials and step potentials.
Step potentials arise during fault conditions, or when current is allowed to flow to earth. During these conditions, the system earth electrode may be subject to a rise in potential. This will create a potential gradient in the surrounding ground, the potential reaching true earth or zero at some distance from the earth electrode. Step Potential is the potential difference between a person’s feet caused by this potential gradient.
Figure 20: Step potential
Touch potentials arise where a metal service connected to another earth system (e.g. DNO earth) is adjacent to OLE. In this situation, a person may be able to simultaneously touch the two earth systems (e.g. an OLE mast and an equipment cabinet). The two earths may be at different potentials, and so a current will flow between them. This potential is the Touch Potential.
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Figure 21: Touch potential
Both these potentials give rise to unacceptable safety risks. Therefore the earthing and bonding design must ensure these potentials are kept at acceptable levels. On AC systems the OLE structures are connected together by being bonded to the traction return rail, which may be one or both rails of each track depending on the signalling system being used. This ensures that a fault on the structure will be cleared quickly. The traction return rails are bonded together at regular intervals, further reducing the system impedance. Other structures are also bonded to traction return, to take account of the possibility that structures which lie within the OLE Zone and Pantograph Zone8 may become energised under mechanical failure conditions. These faults will create a safety risk if not cleared quickly; in particular, signal structures and metal bridges are usually bonded to traction return.
8
BS EN50122-1 “Railway Applications – Fixed Installations – Part 1: Protective Provisions Relating to Electrical Safety and Earthing”; BSI; p7
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Within this equipotential zone all exposed conductors are bonded to ensure that no dangerous potential can arise between them. It is often not desirable to connect LV equipment to traction return. For instance, LV equipment connected to a DNO earth system will not tolerate OLE fault current; additionally, the two earths may be a different potentials, creating unsafe potentials between earths. In this case, it is important to locate this equipment away from the OLE zone and a sufficient distance from traction bonded equipment that touch potentials may not arise. If this is not possible, an insulating shroud or gapping may be used instead. An important factor governing bonding design is that the main function of the rail is not traction bonding. The primary purpose is the guiding of trains; however it is also used by many signalling systems. These use track circuits to detect the presence of a train; the track is electrically sectioned by means of Insulated Block Joints (IBJs); also known as Insulated Rail Joints (IRJs). A voltage is placed across the rails at one end of the track circuit, and a relay detects the voltage at the other end. A train axle shorts the circuit, and this shorting is detected and allows the signaller to locate a train. These track circuits have their own bonding system, and so the traction bonding must be integrated with the signalling bonding. Figure 22: OLE and Pantograph Zones
Where this is the case, one rail of each track is designated the traction return rail – although it also carries track circuit current – and the other is reserved for signalling use. Some types of track circuit eliminate IBJs – which are a reliability issue – by using high frequency AC voltages. These are known as jointless track circuits. Since they are prone to interference from traction fault current, systems using these track circuits are provided with an OLE earth wire. This is connected to traction return rail by means of an impedance unit, which is a low-pass electrical filter that allows traction current to pass while blocking the track circuit frequency. The OLE structures are bonded to the earth wire rather than the traction return rail. The earth wire may be buried, but is usually aerially suspended between structures. Earthing and bonding principles differ for DC systems. This is because DC stray currents can be damaging to metal services and foundation reinforcement.
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5.10.1
AC Systems AC systems are characterised by the creation of a distributed earth system using the general mass of earth; this is formed by using each OLE structure foundation as an earth connection. This system helps to keep the rail potential low in the event of a fault.
5.10.2
DC Systems and Stray Currents DC stray currents are highly undesirable because of the phenomenon of cathodic corrosion. This occurs when current flows continuously from a metal into adjoining soil. The metal is corroded, eventually to such an extent that a hole may appear – a particular issue with metal services adjacent to the DC supply point. The problems which DC stray currents can cause mean that the DC earthing system is entirely different to that of AC systems. The entire system is insulated from the general mass of earth and allowed to float, so that stray currents cannot leave the system. As an additional measure, secondary insulation may be used. This is an additional (reduced) level of insulation inserted between the primary insulation and the mass of earth. A connection to traction return is made between the two sets of insulation; this captures any fault current and prevents it reaching earth. Secondary Insulation
Primary Insulation
Connection to traction return Figure 23: Principal of secondary insulation
This method can also be used on AC or DC systems to provide an additional level of protection against flashovers – for instance, at sensitive overbridge locations where stray currents are to be avoided. 5.10.3
Temporary Earthing Arrangements Temporary earths are required to protect staff against accidental re-energisation during maintenance. These earths are connected between the OLE and the earthed structure at a Designated Earth Position (DEP). Earthing stalks and line guards on the OLE are provided for these connections.
5.10.4
Buffer Sections and Permanent Earths It is often necessary, for the protection of staff during construction works, to permanently earth a section of OLE. This is done by isolating the section of OLE from the live sections around it, and
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installing permanent earths at the limits of the section. These form the safe limits of work for construction staff. Sometimes it is also desirable to create a buffer section between the construction work and live OLE. This is a further section of isolated and earthed OLE which is beyond the safe limit of work. No buffer section
|
Safe limits of work
| Buffer section |
Figure 24: Principal of permanent earthing and buffer sections
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6.
MECHANICAL PRINCIPLES
6.1
Interface with the Pantograph The key interface to be considered in OLE design that that of the contact wire and pantograph or pan – which collects traction current from the OLE, and is so called because of the parallel linkage used to maintain a level pan head.
Carbon Strip
Pan Head
Secondary Suspension
Actuator & Primary Suspension
Horn
Figure 25: A pantograph on test; Old Dalby, UK
The pantograph head is supported by a linkage which ensure the head is always parallel with the contact wire. The pantograph is maintained on the wire by an actuator which is generally hydraulic. This also acts as the primary suspension for the system. Secondary suspension is provided at the pan head.
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The head itself supports one or more rows of carbon strips. These form the interface with the contact wire. Carbon is the favoured material because it has good electrical and thermal conductivity, is self-lubricating, and has a much lower hardness than the contact wire. This means that the bulk of the frictional wear is taken by the train rather than the OLE (since it is easier to replace the carbons than the contact wire). The carbons are glued into an air channel, which is connected to a compressed air circuit. In the event of loss of a carbon strip, air pressure is lost and the pan auto-drop mechanism lowers the pan, thus minimising damage to the OLE. The pan has an operating range; that is, distance over which the mechanical behaviour is broadly the same. The auto-drop mechanism also operates if the pan exceeds the operating range.
Figure 26: Standard UK pan profile9
The pan to contact wire interface is a complex one, comprising as it does three dynamic systems which interact: • • •
9
The Pantograph; The OLE; The train.
TEE-C1-8100715; British Rail
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It is only with the advent of computer modelling that the system interactions have begun to be understood. In simple terms, the pan is arranged to exert an upward force on the contact wire: contact force. This is ideally a constant force; however two factors prevent this in practise. Aerodynamic effects on the pan at speed are different depending on whether the pan is leading or trailing. This can be partially overcome on modern pans by means of aerofoils on the linkage.
Pan Leading
Pan Trailing
Figure 27: Differential wind force on pantograph
The contact force also varies with wire height, due to the mechanical arrangement of the pan linkage and actuator10. The pantograph acts as a spring-mass-damper system, as does the OLE. The contact force creates a vertical displacement on the contact wire – uplift. When the train is moving this uplift combined with the along track movement creates a mechanical wave in the contact wire. Physics – and practical experience – shows that if the train catches up with the wave it creates, the pan loses contact with the OLE. Since the speed of the wave is proportional to the square root of the tension in the wire, the system designer generally sets the contact wire tension so that wave speed > 1.4 x maximum speed of electric trains. A further problem is that of hard spots; any component attached to the contact wire (such as a dropper clip or registration arm) reduces the elasticity locally (a hard spot); each hard spot will reflect a portion of the wave back towards the train. This can lead to loss of contact at the pan. A key factor in the system performance is the elasticity (measured as uplift per unit of contact force) of the OLE. This should ideally be uniform throughout the system. However the reality is that elasticity is less at the OLE structure, due to the support arrangement on the catenary restraining the system, than at the midspan between structures.
10
On high speed systems, this problem is overcome by providing OLE at a constant contact wire height, and locking out the primary suspension. The secondary suspension then caters for small variations in wire height, and the uplift force is nominally constant. The disadvantage of this system is that it is not possible to auto-drop the pan in the event of a dewirement, and significant damage will result.
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Therefore the OLE system designer will match the elasticity differential in the system to the performance requirements. The higher the linespeed, the lower the elasticity differentials. See section 6.5 for details. Heating effects can be significant at the pan/contact wire interface – a particular issue when the train is stationary and aerodynamic cooling is not available. For this reason many trains have limitations on their power consumption when at rest. The contact area must be set according to current requirements; DC pantographs have either a larger contact area, or use multiple pans. Engineering efforts are now concentrating on active pantographs; the contact force is measured many times a second and fed back to a controller which varies the actuator force.
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6.2
Materials Most fittings in modern OLE are galvanised malleable cast iron, galvanised mild steel or aluminium. Covered steel, copper covered steel and stainless steel are used for wire and conductors. Non-ferrous materials are used for certain live fittings in contact with the copper conductors.
6.3
Wire Types The various wires used in the system are also chosen for their electrical and mechanical characteristics.
6.3.1
Contact Wire The contact wire has five main requirements: • • • • •
To transmit electrical energy along its length; To transmit power to the pantograph; To withstand the mechanical stresses placed on it by the tension, environment and passage of trains; To withstand wear from the passage of trains; To facilitate connection for droppers, registration arms and electrical connections. Contact wire cross sections are standardised across the world; a circular section with two grooves is generally used. The groove is used for connection and support purposes. EU standards are centred on 107, 120 and 150mm2 sections. Contact wire material selection is generally a balancing of the mechanical and electrical requirements. The cross section must be kept as small as possible while keeping the conductivity high; however materials with a higher conductivity usually have a lower tensile strength.
11
Figure 28: Typical Contact Wire Cross Section
Copper and Copper alloy is the de facto standard for contact wires, due to Copper’s excellent conductivity, tensile strength and hardness, as well as good performance under temperature change and corrosion resistance. Copper has the advantage of forming a hard but conductive
11
“Contact Lines for Electric Railways”; Kießling, Puschmann, Schmieder; Siemens; p112
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oxidising layer when exposed to air. Alloy additives are added to copper to improve the mechanical performance; however they reduce the conductivity to a greater or lesser extent. Therefore the material is chosen to balance these criteria for the particular system.
Figure 29: Contact Wire Strength against Conductivity12
European contact wires use a system of grooves along the top of the wire to identify the material type13.
Number of Grooves
Type
0
Normal and High Strength Copper
1
Copper-Cadmium Alloy
2
Copper-Silver Alloy
3
Copper-Magnesium Alloy
1 at 24º
Copper-Tin Alloy
It should be noted that UK practise is opposite in terms of Hard Drawn and Cadmium Copper, i.e. HD Copper contact wire has one groove and Cadmium Copper has none.
12
Contact Lines for Electric Railways; Kießling, Puschmann, Schmieder; Siemens; p113 BS EN50149 “Railway Applications – Fixed Installations – Electric Traction – Copper and Copper Grooved Contact Wires”; BSI; p8
13
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6.3.2
Contact Bar It is sometimes not possible, due to restricted space in a tunnel, to provide conventional OLE using flexible wires. In these cases an overhead contact bar is used. This can be either a solid bar with a flat downward contact face, or a grooved bar designed to accept a conventional contact wire.
Figure 30: Overhead contact bar; Paris, France
This system is only used where conventional OLE is not feasible, since the bar requires frequent support, increasing costs, and current collection can suffer due to almost zero elasticity. Contact bar systems are generally limited to speeds below 160kph. 6.3.3
Catenary Wire and Auxiliary Catenary The catenary wire – and the auxiliary catenary, if there is one – has fewer requirements than the contact wire; it is required to transmit electrical energy along its length and to withstand the mechanical stresses placed on it; but it is not required to withstand pantograph wear or transmit energy across a small interface area. For this reason stranded cables are used for catenary wire. These have historically been formed of Steel, Aluminium/Steel composite, or Copper, but current best practise is to use Copper or Copper alloy.
6.3.4
Droppers Dropper wires have two main requirements: • •
To hold the contact wire in the correct position; To withstand the unloading/loading cycle created by the passage of trains.
By default, droppers do not have an electrical function, although a current carrying dropper, with suitable electrical connections, may be used for this purpose.
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Historically, droppers have been made from solid galvanised steel wire; however these are prone to long-term failure due to the constant bending created by train passes. Modern droppers use a stranded Copper alloy cable, which gives better load cycle performance. 6.4
Insulators Insulators are required to separate live parts of the system from earthed parts, and to separate live sections. The insulators chosen for the system must meet the following requirements: • • • • •
Sufficient electrical strength for electrical loads and faults; Sufficient mechanical strength for the location and use; Sufficient creepage path for the environmental contamination at the location; Sufficient durability in areas prone to vandalism; Ability to tolerate pan passes (for contact wire inline insulators only).
The electrical strength is chosen to match the system voltage. The creepage path is the distance around the outside of the insulator; the required creepage path may be achieved by means of ribbed sections, or sheds; or they may simply be long rod insulators. 6.4.1
Materials The material used is dependent on the use, cost and environmental factors. Porcelain has been historically favoured in the UK due to its cost-effectiveness and ease of fabrication. However these are prone to vandalism and to explosive failure. In recent years shed protectors have been added to these insulators; these comprise a rubber sleeve which fits tightly around the shed. This helps the shed to withstand vandalism, and can help to hold together a damaged insulator. Glass is used extensively in Europe, being more robust than porcelain, but also more expensive. Plastic (or polymeric) insulators are now favoured in the UK, as they are lighter and smaller than their porcelain or glass counterparts, and can be made in antivandal forms, where the sheds deform rather than break on impact.
Figure 31: Lightweight shedded polymeric 25kV insulator; WCML, UK
Plastic insulating materials may also be formed into rod insulators. These are used at locations where clearances to the pan are small, and a shedded insulator would be too large.
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Figure 32: Polymeric 25kV rod tension insulator; Stone, UK
Glass Fibre insulators are used where a rod insulator is required to withstand a bending load is. These are used on bridge arms (see section 6.11.8). Plastic materials are also used extensively for rope insulators on tram systems. 6.4.2
Mechanical Requirements The mechanical load requirements of the insulator depend on the use. Tension insulators are designed to take a purely tension load. They are used as cut-in insulation in wire runs, and as catenary supports. They may be formed as individual shed components; these are joined together by means of a cap and pin arrangement to form an insulator of the required electrical strength.
Figure 33: 25kV shedded porcelain tension insulator formed of 3 cap & pin sections; Norton Bridge, UK
Post insulators are designed to take bending and compression loads, and are used to support feeder wires and support catenaries.
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Figure 34: 25kV shedded porcelain post insulator; WCML, UK
Switching Insulators are designed to take a torsional moment and are used in torsion-tube operated switches.
Figure 35: 25kV porcelain switching insulators with shed protectors; Norton Bridge, UK
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Glass Bead Insulators are formed of glass beads threaded onto a rod; they are used in circumstances where an insulator is required in the in running contact wire; for instance, at inline neutral sections (see section 6.9.2). This type of insulator needs regular cleaning and their use is therefore minimised.
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6.5
Suspension Arrangements Various suspension systems have been developed for the different performance requirements of OLE. At its simplest, OLE can consist of a contact wire suspended directly from support structures. This is known as tramway or trolley OLE.
Figure 36: Tramway OLE
Although simplest in terms of engineering, the elasticity is zero at the support point; for this reason, it is used only on very low speed (≤ 30kph) lines for tram networks and heavy rail sidings. The tram system can be improved by the addition of a stitch (also known as a bridle). Here the support is transferred to the stitch wire, which in turn suspends the contact wire. The length of stitch may be varied for the particular system.
Figure 37: Stitched tramway OLE
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The stitch creates some elasticity at the support; this type of suspension is often used on tram systems, and gives good current collection up to 80kph. The next step is to create a suspension wire running the whole length of the system. This is the simple catenary system – so called because a wire suspended in space describes a catenary curve under gravity. The contact wire is suspended from the catenary by vertical droppers.
Figure 38: Simple catenary OLE
This system gives better elasticity at the support and is the simplest system adequate for mainline railways. For this reason it is widely used in the UK and Europe, and gives good current collection up to 120kph. In an attempt to further reduce the elasticity variation, the next system use presagged contact wire. Rather than keeping the contact wire flat across the span, a deliberate amount of sag is introduced – typically of 1/1000 of the span length (the distance between structures).
Figure 39: Presagged simple catenary OLE
The purpose of the presag is to compensate for the greater elasticity at the midspan, since the uplifted contact wire position at midspan is closer to the uplifted position at the support. This
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system has found favour in the UK (≤ 200kph) and France (≤ 300kph). It should be noted that this system powered the current rail world speed record holder to 574kph. It is also possible to introduce a stitch in simple catenary. The tension in the stitch can be set so as to reduce the elasticity even further.
Figure 40: Stitched simple catenary OLE
This system is favoured on high speed lines in Germany, where it is used for speeds up to 300kph. A further development is the introduction of a third wire – the auxiliary catenary. This gives us the compound catenary system.
Figure 41: Compound catenary OLE
This also gives very low elasticity variation, and many of the first mainline systems in the UK were compound. They have since fallen out of favour in the UK due to the complexity and maintenance requirements. Elsewhere in the world it is still widely used, notably in Japan, where the high speed Shinkansen lines make extensive use of compound equipment at speeds up to 300kph.
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6.6
Tensioning Arrangements OLE must be tensioned to maintain the contact wire height under gravity. The key parameter for tensioning is the requirement to allow for expansion and contraction of the wires with varying temperature. A complete length of OLE (or wire run) may expand or contract as much as 1.5 metres over a 50°C temperature operating range, and this has a major effect on tensioning arrangements. The simplest system is known as Fixed Termination (FT). Here the catenary is fixed and tensioned at every structure. The contact wire is tensioned at each end, and allowed to expand and contract in between, but is restrained by the droppers attached to the catenary.
Figure 42: Fixed termination OLE
As temperature is increased, the contact wire will sag between structures. As it decreases, it will hog. For this reason, current collection is a significant problem for FT systems. It is generally only used on tram and sidings systems. The standard system for medium and high speeds is the Auto Tensioned (AT, also known as balance weight) system. Here the catenary is fixed only in the centre of the wire run at the midpoint anchor; the whole system is free to move around this fixed point. Constant tension is provided by a set of balance weights attached through to the catenary and contact wire. This is done at a mechanical ratio of either 3:1 or 5:1 via pulleys or drumwheels, which reduce the size of the weight stack required. The weights travel up and down as the system expands and contracts. Along track movement is provided for at structures by pulleys, flexible links or pivoted cantilevers. The tension is not entirely constant, varying slightly due to the drag caused by cantilevers pivoting the wire away from the neutral temperature position. However with good design, the tension variation can be kept below 3%.
Figure 43: Auto tensioned OLE
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AT systems are used worldwide at all speeds. Other tensioning devices are sometimes substituted, such as hydraulic or pneumatic systems where space is restricted. Contact wire tensions run from 8kN for slow speed systems, right up to 40kN (used for the world speed record attempt). Typically, mainline systems run between 10 and 15kN. 6.7
Transferring the Pan between Tension Lengths The length of a wire run is limited due to the maximum drag requirements detailed above (as an example, UK mainline wire runs are limited to ≤ 1970 metres) – as well as practical considerations such as maximum cable length on the cable drum. Therefore arrangements must be made to transfer the pan from one wire run to the next. This transfer arrangement is known as an overlap. At its simplest, an overlap is a purely mechanical arrangement. However, it is also used as a convenient place to create an electrical break in the OLE for sectioning purposes. The overlap type is defined by two parameters; the number of spans of parallel running; and whether it is uninsulated (or construction) or insulated. An insulated overlap takes advantage of the fact that each wire run is out of running (not in contact with the pan) at some point. Therefore insulation may be inserted in each wire without the hard spot of an in running type insulator. A switch or Booster Transformer may then be connected around the electrical break. It should be noted that, when used as a electrical break for a Booster Transformer, a train brought to a stand in the overlap will short out the BT. This can lead to arcing and contact wire burnout; for this reason signals are not placed at overlaps.
6.7.1
Zero Span Overlap The simplest form of overlap is the zero span. This has a single point transfer, with no spans of parallel running.
Figure 44: Uninsulated zero span overlap
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Figure 45: Insulated zero span overlap
The zero span arrangement is suitable for low speeds on tram and siding systems only, due to the poor dynamics of the transfer point.
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6.7.2
Single Span Overlap Higher speeds are achievable using a single span overlap. This has a single span of parallel running. The pan is transferred gradually from one wire run to the other; within the parallel running section, it is in contact with both.
Figure 46: Uninsulated single span overlap
Figure 47: Insulated single span overlap
The single span overlap is used worldwide, and is the standard for UK heavy rail up to 200kph.
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6.7.3
Multiple Span Overlaps For higher speeds, the increased elasticity variation created by the wire being lifted out of running becomes a barrier to good current collection. Therefore the number of spans of parallel running is increased. Two span overlaps can lead to poor dynamics due to the presence of the structure at the midpoint; therefore a three span overlap is preferred.
Figure 48: Uninsulated three span overlap
Figure 49: Insulated three span overlap
The amount of lift at the first out of running location is small; the wire is lifted further at the next support. This system is used on European high speed lines at up to 300kph. Some high speed lines also use five and seven span overlaps.
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6.8
Turnout Wiring Special arrangements are required where tracks diverge or converge, to ensure continuity of current collection.
6.8.1
Low Speed Tangential Method The simplest way to wire a turnout is to use an additional wire run for the turnout, with no connection between the two wire runs. This is satisfactory for low speeds, but as speed rises so does the uplift. This leads to the situation where the wire run carrying the pantograph rises, but the other wire run does not, leading to the risk of hookover.
Figure 50: Low Speed Tangential Turnout Wiring
This method is used extensively on trams systems and in heavy rail sidings. 6.8.2
Cross Contact Method One method used to minimise the hookover risk is to use a Cross Contact arrangement. In this case the two wire runs cross, and a Cross Contact bar is provided at the contact wire crossing point. The cross contact bar ties the two wires together, while allowing for along track movement. This ensures that the wire run which is not being lifted by the pan follows the lifted wire, and hookover risk is minimised.
Figure 51: Cross contact turnout wiring
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The mainline wire should always be placed below the crossover wire run. The cross contact system is used extensively in UK heavy rail, although the cross contact bar can cause a hard spot if poorly designed.
Figure 52: Cross contact arrangement
High speed cross contact has been successfully used in Europe, with a specially-designed lightweight cross contact bar and appropriate droppering. 6.8.3
Cross-Droppered Cross Contact Method A variation on the Cross Contact method may be achieved by the use of Cross Droppering. This entails droppering the mainline catenary to the crossover contact wire in the vicinity of the Cross Contact bar, to spread the lifting effect of the Cross Contact over a longer length. This system has been used in some UK turnout wiring at speeds up to 125mph.
FFigure 53: Cross-Droppering Arrangement, Brinklow, UK
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6.8.4
High Speed Tangential Method In an attempt to eliminate the hard spot associated with the Cross Contact bar, a high speed Tangential arrangement has been developed in the UK. This uses a complex droppering arrangement and a span where the two wire runs are in parallel to ensure that the pantograph picks up the crossover wire run without hookover risk.
6.8.5
High Speed Three Wire System Some high speed systems use a three wire arrangement at the turnout to achieve transfer of the pan without hard spots. Two wires are routed down the crossover, and transfer is achieved by careful positioning of the three wires at the turnout structure, where a triple cantilever is provided. An additional benefit is that the section break between the two tracks can be provided by configuring the two crossover wire runs as an insulated overlap (see section 6.7), thus removing the need for a section insulator (see section 6.9.1). This is not standard in the UK, but is used on the Channel Tunnel Rail Link.
6.9
Other Electrical Break Devices
6.9.1
Section Insulator Although overlaps are used wherever possible to create section breaks, there are times when additional breaks are required for switching and sectioning. At these locations, a section insulator (SI) is used. This is an insulator which sits in the contact wire and catenary, and allows the pan to pass over it. An SI consists of a standard insulator in the catenary and an arrangement of insulator and skids in the contact wire; this allows the pantograph to pass over it. The detailed arrangement of SIs varies, but there are two basic types; the continuous type, where the train is provided with power at all times; and the discontinuous type, where there is a short section with no power. The discontinuous type is simpler, but has obvious drawbacks, as there is a discontinuity of current collection, and these are only used in low voltage systems. The continuous type is better operationally, but requires an overlapping skid arrangement which is more complex to maintain.
Insulator
Insulator
Figure 54: Discontinuous SI
Glass bead insulator
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Glass bead insulator Figure 55: Continuous SI (plan view)
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SIs are a major hard spot in OLE; for this reason their use is minimised, and generally restricted to crossovers, sidings and station areas where speeds are lower. They should be supported at a structure wherever possible. They are also difficult to set up, and there are more onerous rules on horizontal position, depending on the width of the SI. Figure 56: High speed continuous SI; Rugby, UK
6.9.2
Neutral Sections An electrical break is required wherever different supply phases meet – or, for that matter, where there is a change of system voltage as occurs at many European interfaces. At these locations a neutral section is used. This is a section of earthed OLE, with a line voltage strength insulator either side (since the total strength of the insulation must be √2 x line voltage). The train must not draw power through the neutral section, since an arc would be drawn to earth. For this reason the train power is tripped off by a trackside Automatic Power Controller (APC) magnet, which operates the train’s circuit breaker via a relay. When the train has cleared the neutral section, the breaker is closed by a second APC magnet.
Train power shut off
Train power switched on
Direction of travel
Figure 57: Principle of a neutral section
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Figure 58: APC magnets at a neutral section
There are two main types of neutral section; the inline type, and the overlap type. The inline type consists of either a glass bead insulator (over which a pan is able to run), or a high speed section insulator, placed either side of the dead section. Sacrificial arcing horns are provided in the event that a train draws power through the dead section. These types are standard on mainlines up to 200kph; the geometry can be difficult to maintain, and the glass bead insulators require regular cleaning.
Figure 59: Arthur Flury type (left) and BICC glass bead type (right) neutral sections; Rugby, UK
The inline type is the standard for speeds up to 200kph. Above this speed, dynamic performance is significantly affected, and the overlap type is used.
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The overlap type consists of two overlaps in quick succession; the first transfers the pan from the first live wire run to an electrically floating wire run; the second transfers the pan back onto a second live wire run. Train power is switched off in the normal way. This gives much better dynamic performance, but requires a more complex OLE arrangement. It is used on the CTRL and European high speed lines. Neutral Sections are found at feeder stations and midpoint track sectioning locations. Care must be taken to site signals so that there is no risk of a train becoming stranded at a neutral section. 6.10
Mechanical Clearances It is essential to maintain mechanical clearances between static parts of the system, and those parts which move. Key mechanical clearances are: • • •
6.11
Pan to registration arm; Pan to drop bracket; Registration arm to supporting assembly.
OLE structures OLE structures have both a mechanical and electrical role to play. Mechanically, they must be capable of holding the wires at their design positions, and must only deflect under wind within the design deflection limits. Electrically, they must be capable of withstanding the mechanical stress and thermal stress caused by voltage and current spikes under fault conditions. For AC systems, the structures and their foundations also form a distributed earth system (see section 5.10.1). For DC systems, stray currents (see section 5.10.2) mean structures must be insulated from earth. Most systems use standard structure designs which are held in Basic Design Ranges (see section 6.12.8). These standard structure designs are pre-approved for use in appropriate locations. A structure may be used to support the OLE (to fix the vertical position). This is usually done at the catenary, by means of a clamp, link or pulley; the contact wire vertical restraint is via the droppers. A structure may also be used to register the OLE (to fix the horizontal position). This is done at the catenary, as above, and at the contact wire, by means of a registration arm. This is free to move vertically to take account of uplift, and (for AT equipment) along track to take account of movement with temperature. It is sometimes necessary to use a structure to support only (e.g. to support the mass of an SI), or to register only (to get a wire run around a heavy curve). These structures are denoted as Not Registered (NR) and Not Supported (NS). Sometimes a structure may not carry out either role (e.g. a switching structure carrying a feed onto the OLE); these are designated Not Supported or Registered (NSR). The structure must be capable of withstanding a number of loads: • •
The static loads in the system; The live loads created by the action of wind and weight of ice;
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• •
Loads caused by a dewirement; Loads created during construction, both by staff working on the structure, and partial installation of equipment.
OLE structures are identified by their structure number and their along track location. The location may be given in kilometres or miles and feet from the zero point of the route, depending on the vintage of the system. In the UK, the structure number is in the form [Route code][Unit]/[Number]. The route code refers to the line of route which the structure is on; the unit is either the mile of kilometre which the structure is in, and the number is the number of the structure in the unit. For instance, the first structure at the zero point at Paddington is J00/01; the route code is J, and the structure is the first in the ‘0’ kilometre. Subsequent structures are J00/02, J00/03….until the 1 kilometre mark is reached. The first structure past this mark is J01/01, then J01/02 etc. Where new structures are introduced on an existing electrified route, a letter suffix is used; e.g. if a new structure is required between J01/04 and J01/05, it would be numbered J01/04A. A second new structure at this location would be numbered J01/04B, and so on. A list of UK route codes is given in APPENDIX I. There are several different types of OLE structure, each appropriate to a particular use.
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6.11.1
Single Cantilever The single cantilever is the basic building block of most OLE systems. It is designed to support one wire run over one track.
Figure 60: Typical single cantilever
The single cantilever is cheap, easy to construct and adjust, and is the standard structure for use on a two track railway.
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6.11.2
Double Cantilever It is often necessary, particularly at crossovers and overlaps, to support two wire runs over one track. The simplest way to do this is by means of a double cantilever.
Figure 61: Typical double cantilever
The two cantilever arms are separated along track on horizontal spreader channels, and separated along track to ensure that under extreme temperatures (and thus along track movement) the assemblies do not clash. Some high speed railways place an overlap on
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crossovers to avoid using an SI (see section 6.8.5); these systems use a triple cantilever on the same principal as the double cantilever. The double cantilever illustrates the important principal of Mechanically Independent Registration (MIR). This means that each wire run has a support and registration which is independent of any other. In the event of wire run 1 being damaged, wire run 2 will continue to operate within geometrical limits. This has important implications for OLE availability in the event of a dewirement. 6.11.3
Back to Back Cantilever Where there is sufficient clearance, a back to back cantilever may be used to support wire runs over two tracks.
Figure 62: Typical back to back cantilever
This has the advantage of requiring less materials than a pair of single cantilevers. However, the maintenance requirements are more onerous, since the live equipment on one track must be isolated in order to work on the second track, meaning the railway is closed to electric services.
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6.11.4
Twin Track Cantilever It is often the case that foundation space is only available on one side of a two track railway; for instance, signalling equipment may be present on the other side. In this case, the Twin Track Cantilever (TTC) is used to support several equipments over two tracks.
Figure 63: Typical twin track cantilever
The TTC will experience a high overturning moment at the base of the mast, and for this reason the foundation will be larger to resist the moment. TTCs should be used only where single cantilevers or portals are not suitable. The TTC above has MIRs, since the equipments are on separate cantilevers. It is possible to use a span wire strung between the TTC mast and a nose assembly at the extremity of the TTC boom; however this arrangement will not be mechanically independent, and loss of wire run 1 will lead to loss of tension in the span wire, and subsequently wire run 2 will lose restraint.
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6.11.5
Portals For railways with more than two tracks, it is not possible to use single cantilevers without separating tracks, which leads to additional land-take and expense. Therefore it the standard structure for a multi-track railway is the portal.
Figure 64: Typical portal for four tracks with wideway
The structure shown also has MIRs. It is relatively easy to make adjustments on these structures; however construction or demolition requires a possession (i.e. closure) of the railway, and isolation and earthing of all OLE. The use of a crane, along with good access, is also necessary. For this reason, feasibility of construction must be considered in the design of a portal railway. A portal may be either a fixed or hinged type. The fixed type has rigid bolted connections at each foundation and at each corner; this means all structure loads are transferred to the foundation. A hinged portal will have hinge pin connections, either at the foundations or at the connections between the mast and boom. With this arrangement, only the vertical loads are transferred to the foundation – an arrangement which is especially useful on viaducts, where the structure may not be capable of withstanding high loads. Much like the TTC, it is possible to use a span wire strung between the portal masts. This arrangement is not mechanically independent, and the same issues arise as with a span wire TTC. Figure 65: Hinge-based portal leg on a viaduct, showing hinge pin
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It should be noted that the configuration above could equally be serviced using a back to back twin track cantilever or two single cantilevers and a back to back cantilever. 6.11.6
Headspans An alternative to the portal in multi-track areas is the headspan structure. This structure comprises two extended masts, with one or two horizontal tensioned wires (the upper and lower cross span wires) strung between them to locate the OLE. A third headspan wire supports the overall arrangement. The headspan has the advantage of being cheaper and easier to install than the equivalent portal. The headspan is a load-balanced system; the tensions in the wire runs themselves contribute to the geometric stability.
Figure 66: Typical headspan for four tracks
If a wire run breaks, the design geometry is lost and all other wire runs will be out of balance. This type of structure is not mechanically independent, and a failure means all tracks are lost to electric services. Headspans require regular maintenance to check the span wire tensions, and adjustment of the equipment tends to lead to design and replacement of assemblies. For high
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speed lines, the mechanical wave created by the passage of a train can also affect adjacent wire runs. Because of this, headspans are best suited to low speed applications where low capital cost is more important than high availability or performance. For UK heavy rail, headspans are present in large numbers; however their poor availability means they a prohibited for new designs on mainlines. 6.11.7
Spanwire Portals A compromise may be achieved between the performance advantage of a portal and the cost advantage of a headspan – the result is a spanwire portal. This uses a portal boom but with a spanwire to fix the registration equipment, thus avoiding expensive stovepipe arrangements. This is not an MIR arrangement, and is generally confined to sidings or complex areas.
Figure 67: Typical spanwire portal
6.11.8
Bridge and Tunnel Supports Wherever possible, OLE passes through bridges without being connected to them. These bridges are free running. Where it is not possible to achieve this, it is necessary to attach one or
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more support and/or registration assemblies to the bridge. This can be done in a number of ways, depending on the type of bridge and the clearance restrictions. Many existing bridges and tunnels are of Victorian build; these are typically arched, and pose particular problems for electrical clearances. These can be wired using tunnel cantilevers or tunnel arms. The former is supported from the centre of the arch; the latter from the outside.
Figure 68: Tunnel cantilever arrangement
Figure 69: Tunnel arm arrangement
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Modern bridges often use flat concrete decks, which pose an even greater problem if the deck was not designed to take account of OLE clearances. In this case a glass fibre bridge arm can be used. The arm both supports and registers with OLE. The insulator material has some flexibility, and this provides for a reduced amount of uplift to assist with clearances. The end fitting, which is the highest point of the assembly, is carefully designed to minimise the electrical stress between the arm and the bridge.
Figure 70: Glass fibre bridge arm; Ripple Lane, UK
At overbridge locations, the system height (the distance between the contact wire and catenary) is reduced and contenary used; or even eliminated by using twin contact; contenary is spliced into the catenary and then brought down until it is side by side with the contact wire.
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6.11.9
Anchors Anchors are required to terminate wire runs, and at the midpoint of an auto-tensioned wire run. They must be capable of withstanding overturning moment created by the tension in the contact wire and catenary, both under normal operation and in the event of a wire breakage. Terminating Anchors take a variety of forms. A stand alone anchor structure may be used; although wherever possible, an existing cantilever, TTC, headspan or portal should be used to keep steelwork costs down. These anchors may be of the self-supporting variety; that is, the steel section and the foundation withstand the entire overturning moment; or of the back-tied variety, where a tie wire or rod extends from the top of the structure down to a mass foundation at a short distance from the structure. The back-tied type has the advantage that a significant portion of the tension load is transferred to the mass foundation, and the steel section and main foundation size may be reduced. The self-supporting type is used where there is no space for a back-tie. Terminating anchors may be of the balance weight type, for use at the end of an auto-tensioned wire run, or of the fixed type; these are used at the end of fixed termination wire runs, or for one end of a short auto-tensioned run where a midpoint anchor is not required.
Figure 71: Back-tied balance weight anchor with 3:1 anti-fall drumwheel and twin weight stacks; Newbold, UK
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The arrangement of a midpoint anchor depends on the type of structures in use. For cantilevers, the MPA is arranged by means of a tie wire which is clamped to the catenary. This wire is terminated at the structure either side to form the restraint.
Figure 72: MPA arrangement for cantilevers
For portals, a direct connection to the portal boom via insulators is generally used. The connection is jumpered to maintain electrical continuity.
Figure 73: Typical MPA arrangement for portals; Norton Bridge, UK
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For headspans, the MPA cannot be a point restraint due to the flexible nature of the system. Therefore a distributed MPA is used; the catenary is clamped to the span wire over several structures to distribute the load.
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6.12
OLE Foundations Similarly to OLE structures, OLE foundations have both a mechanical role (withstanding the loads) and an electrical role – facilitating fault current flow for AC systems, preventing it for DC systems – to play. The main component of mechanical load on an OLE foundation is the overturning moment at the base of the mast. This determines the configuration of the foundation, and there are a number of different types, each designed to resist this moment. The type of foundation chosen must be matched to the ground conditions, ground profile and construction methodology.
6.12.1
Planted Mast Foundations Planted Mast Foundations are formed by setting a polystyrene former into a previously dug hole, and pouring concrete around the former. The former is then burned away, and an extended mast placed into the foundation and grouted. Although extensively used in early OLE systems, they are not favoured, due to the requirement to support the mast while the foundation is curing.
6.12.2
Side Bearing Concrete Foundations A side bearing concrete foundation comprises a cuboid of reinforced concrete, with the long side arranged vertically. The overturning moment is resisted by this long side bearing on the surrounding ground. A hole is dug, a reinforced steel cage placed in the hole, the foundation poured, and a dressed concrete cap incorporating holding down bolts poured on top of the main foundation. Figure 74: Planted mast; WCML
The holding down bolts protrude from the cap, and a bolted base mast is attached. These foundations are favoured for level ground with a high bearing pressure and good access for appropriate plant. 6.12.3
Mass Concrete Foundations These are used to attach back-ties for anchor structures. They comprise a cuboid of reinforced concrete dug into the ground; an attachment point is provided for terminating the back-tie.
6.12.4
Piled Foundations Modern piling techniques offer a number of solutions, which are generally used whether either ground conditions are poor, or the construction is to take advantage of the economies of “assembly line” installation.
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Like the side bearing concrete foundation, the moment is resisted either by the long side of the pile bearing against the surrounding ground. All the types of pile detailed below, with the exception of the driven steel type, have a dressed concrete cap added after piling, to give controlled water runoff and to take the holding down bolts for a bolted base mast. A bored pile foundation consists of a reinforced concrete cylinder similar to the side bearing type. A boring rig is used to dig the hole in stages; concrete is poured onto a reinforced steel cage placed in the hole. This piling method is only suitable for good ground; the hole has a tendency to collapse before the concrete can be poured. An augered pile (or to give its full name, the continuous flight augered pile) is similar to a bored pile, except that the hole is created in one operation; as the auger is withdrawn, concrete is pumped down the hollow shaft of the auger and into the hole from the bottom upward. A reinforced steel cage is placed into the concrete before it cures. This avoids the problem of hole collapse. A driven concrete pile consists of a precast reinforced concrete pile, which is driven into the ground by a series of blows from a piling rig. A driven steel tube pile uses the same installation technique as the driven concrete type, but the pile is a hollow steel cylinder. This makes it much easier to drive; it also allows driving of long piles in sections, as each can be bolted on as the previous section reaches ground level. The holding down bolts can be pre-welded into the top of the pile, making it an attractive proposition for rapid installation. The disadvantage is that the steel can corrode if placed in acidic ground conditions. The screw pile comprises a self-driving bore which forms the foundation itself; it is screwed into the ground, and the pile cap added. Figure 75: Driven steel tube pile; Brinklow, UK 6.12.5
Gravity Foundations A gravity foundation (also known as a gravity pad) takes the form of a shallow cuboid of reinforced concrete, arranged to form a large footprint. The pad is dug a short way into the ground; the moment is resisted by the underside of the pad bearing against the ground below it on the compression side, and the mass of the foundation on the tension side.
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Figure 76: TTC with gravity pad; Aveley Marsh, UK
The gravity foundation is used in locations where depth is not available, such as on viaducts, or where ground conditions below the surface are poor. 6.12.6
Rock Foundations Rock foundations are used where the railway runs through an area where bedrock is on the surface; usually at cliff areas or mountain passes. The rock is usually dressed with a flat concrete bearing face, and holding down bolts are drilled into the rock and bonded with a suitable adhesive.
6.12.7
Attachment to Other Infrastructure In restricted clearance areas there is often not room for a dedicated OLE structure foundation. Typically, these areas are at: • • • •
Stations; Overbridges; Underbridges; Cuttings with retaining walls.
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In these areas it is necessary to attached OLE structures or assemblies to the existing infrastructure. For these attachments, the OLE designer must take account of the following; • • • • • • • 6.12.8
Condition of the structure; Load capacity of the structure; Ownership of the structure (many bridge structures are owned by third parties); Effect of fault current on structure and other systems and utilities attached to it; Electrical clearances; Fixing arrangements; Safety of the public.
Basic Design Ranges The Basic Design Range of each OLE system generally contains a number of foundations, which are pre-approved for use at appropriate locations. Foundations are allocated based on the constraints at the location, results from geotechnical investigations, and the construction methodology. Where standard foundations cannot be allocated, specially designed foundations are used, which are subject to the civil/structural Form A and Form B design procedures.
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6.13
OLE Assemblies Overview The terminology used in OLE design and construction is often not clear. The following diagrams give a broad overview of the main terms used. For more detail see RYE/EAN/045 “Glossary of Electrification Terms”. Below is a ‘pull-off’ cantilever; so-called because the assembly pulls the wire toward the mast.
Return Conductor Top Tube (or Tie)
Strut Tube
Registration Tube
Mast
Windstay Registration Arm Catenary Contact Wire
Dropper
Foundation
Figure 77: Pull-off single cantilever
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Below is a ‘push-off’ cantilever (also called a ‘push-pull cantilever); so-called because the assembly pushes the wire away from the mast.
Nose Dropper Clevis
Top & Bottom Mast Brackets
Drop Bracket
Z Dropper
In-span jumper
Figure 78: Push-off single cantilever
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6.14
OLE Geometry The requirement for continuous contact between the OLE and the pan means that the geometry of the system must be kept with strict limits. It is important ensure that the OLE geometry complies with the rules set out below. Failure to do so will result in a failure to meet the RAMS requirements (see section 4.4) – for instance by compromising the reliability. The contact wire geometry is defined in terms of height and stagger at each structure. The height is measured parallel to the track centreline; the stagger as the offset perpendicular to it.
Figure 79: Height and stagger for OLE
6.14.1
Vertical Limitations As stated previously, the pantograph has a vertical operating range. Going below the lower limit will potentially lead to train damage; going above the upper limit will lead to the auto-drop mechanism activating.
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This leads to the concept of minimum contact wire height and maximum contact wire height. Above the upper limit, the pan will auto-drop leading to loss of power; below the minimum electrical clearances to the train will be compromised. The requirement for height variation arises from the need to achieve minimum safe clearance for road traffic at level crossings, and to operate through pre-electrification era overbridges. Modern high speed lines are usually built as brand new construction, with no there are no level crossings (due to the unacceptable safety risks), and overbridges are built to give sufficient clearance. In these circumstances it is possible to maintain a constant contact wire height throughout the route. For other systems, where there is a need for height variation, the pantograph has a maximum rate of rise per second, above which it will not be able to follow the wire. Therefore the rate of rise and fall of the wire over the pan must be controlled if good current collection is to be achieved. This gives rise to the concept of contact wire gradient. The maximum gradient is generally proportional to the maximum linespeed: GMAX ≤ 1 in (5v) where v is measured in mph Additionally, areas of change are subjected to profile rules.
overbridge
level
GMAX/2
GMAX
GMAX/2
level
GMAX/2 GMAX
Figure 80: Typical contact wire profile (y axis exaggerated)
Note that gradients are always measured in relation to track rather than gravity. The maximum gradient generally can only be achieved by means of an intermediate span with a half maximum gradient. Gradient can be quoted either as “x%” (used in Europe) or as “1 in x” (used in the UK). It is particularly important to manage this change at overbridges; poorly graded OLE can lead to long term current collection problems and locally increased contact wire wear. The design uplift is the uplift the system must be capable of catering for without failure. It is a function of the maximum uplift derived from system modelling, and a safety factor for the uplift. For European systems, the safety factor is normally 2. For bridge arrangements, where clearances are restricted, support and registration assemblies which restrict the uplift are available.
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An important consideration is the span differential for each structure. This is the difference between the span lengths either side of the structure. A large span differential corresponds to a large elasticity differential between the two sections of OLE, and this will affect current collection. Therefore a maximum span differential is defined. 6.14.2
Horizontal Limitations The pantograph also has a horizontal operating range. Contact wire deviation outside this limit will lead to the pan coming off the wire; it will then rise without restraint. As the wire comes back toward the pan, dewirement is a certainty. The horizontal displacement of the contact wire from the pantograph centre line at registration points is known as stagger. Stagger is required to ensure even pantograph carbon wear and carry overhead line around a curve. This leads to the concept of maximum stagger. The maximum stagger is not usually a constant; as contact wire height increases, the sway of the pan created by train roll increases. This reduces the effective operating range; the maximum stagger is reduced, usually linearly, to compensate. The stagger is achieved by restraining the contact wire with a registration arm. This assembly is attached to the structure by means of a drop bracket. The registration arm length is matched to the stagger so that the pantograph does not come into contact with the drop bracket when the registration arm is raised to the design uplift. In particular, some arms are designed to reach over the pan centre line; others are not. Figure 81: Determining minimum stagger
This leads to the concept of minimum registration arm stagger. An associated rule is that of heel setting. This is the vertical distance from the contact wire to the attachment of the registration arm to the drop bracket. This, combined with the maximum registration arm stagger, ensures the pan does not hit the registration assemblies. The point where the horizontal operating range is most at risk is at the midspan between structures. This is because wind causes blowoff of the contact wire from its still air condition.
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This leads to the concept of maximum total offset (MTO). This is the sum of Midspan Offset (MSO), blowoff, and stagger effect. The MTO for each span must be less than the Maximum Permissible Offset (MPO).
Figure 82: MSO, blowoff, stagger effect and MTO
MSO is the distance the contact wire is from the track centre-line under still air conditions midway between registration points. MSO is a function of the stagger at either end of the span; and the track curvature, measured as versine or stringline. It is important to keep MSO as low as possible, since the other factors in the MTO are less easy to control. Versine is measured using a straight line drawn from the running rail at one structure to the same rail at the next structure; the distance between this line and the same rail at the midpoint is the versine. Versine is a function of span length and track radius.
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Thus the designer can control the MSO by varying the structure spacing and/or the staggers. Blowoff is the amount through which the contact wire is moved at the midspan as a result of maximum wind conditions. It is a function of the contact wire tension, the contact wire drag factor (which is a measure of the aerodynamic drag of the wire), the contact wire surface area (diameter × length), and the design windspeed. The design windspeed is calculated using the base windspeed for the area; this is a statisticallyderived measure of the highest windspeed which is likely to be seen over the life of the system (typically 50 years). This base windspeed is modified by factors reflecting the local topography to give the design windspeed. The design windspeeds are determined by the OLE designer as a result of a windspeed survey. Stagger effect is the difference between the worst deviation in the span under wind, and the deviation at midspan. When the stagger at each end of the span is not the same in magnitude and direction, the MTO may not occur at midspan. The stagger effect figure is added to the midspan offset and blowoff to find the MTO. Similarly to maximum stagger, MPO is not a constant, due to the increased sway of the pan with height. MPO is reduced, usually linearly, to compensate. Sweep is the distance the contact wire moves across the pantograph in the course of travelling between two registration points, be it either from one side or from one side to the centre line and back again. Sweep Ratio is the ratio of this distance to the span length; it is thus a measure of the speed of the contact wire movement over the pan. It is important to keep the sweep ratio between the minimum sweep ratio and maximum sweep ratio; if the contact wire moves too little, a groove may be worn in the carbon; too much and undesirable frictional heating effects come into play.
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6.14.3
Load Limitations The contact wire and catenary are subject to a number of mechanical loads. These are categorised as; • • • •
Permanent vertical loads; the vertical loads caused by self weight of the equipment; Ice vertical loads; the additional live vertical loads created by the weight of ice on the wire; Permanent radial loads; dead loads caused by a component of the wire tension being transferred to a structure when the wire changes direction, e.g. on a curve; Wind radial loads; additional live radial loads created by the action of wind on the wire.
The support and registration components must be capable of withstanding all of these loads in combination. In particular, the permanent and wind loads affect the operation of the support and registration assemblies. At contact wire level, many registration arms behave poorly if not held in tension. If there is little or no tension, the registration arm will “chatter” at the drop bracket fitting, and wear will occur. If there is a compression load, the registration arm may flip around, with catastrophic results at the next train passage. At the other extreme, too much tension can lead to failure of the registration arm fittings. Most systems have special registration arms designed specifically to take a compression load; there are occasions where it is impossible to avoid without significant extra cost. Therefore it is important to keep the registration arm load within design limits. The load on the registration arm is a combination of radial and vertical loads; they must be balanced to achieve the desired result. In practise the vertical loads tend to be fixed for a given span length; therefore the radial load is adjusted by means of stagger and versine. The effect of versine on radial load is approximately four times that of the staggers, so structure spacing on curves is key. The same limitations apply to a lesser extent on the catenary support; there is a maximum vertical and radial load. Many support arrangements are capable of taking compression loads; however care should be taken with cantilever arrangements which use a top tie wire rather than a top tube. These can collapse if sufficient compressive radial load is applied. A Factor of Safety (FoS) is applied to the maximum loads. This factor of safety is generally higher for structures than for registration assemblies; for instance, UK heavy rail standards specify a FoS of 2.5 for structures and foundations, and 1 for registration assemblies. This is in recognition of the critical nature of the structures.
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7.
OLE DESIGN AND CONSTRUCTION PROCESSES The design of OLE is subject to a strict process designed to ensure that designs are safe, robust and meet the performance criteria. These procedures are country-specific; however the principles are the same for all systems. This document will focus on the general principals, with examples of UK practise used to demonstrate the process.
7.1
Process Overview The design and implementation process from beginning to end is generally as follows: 1. 2. 3. 4. 5.
The client defines the scope; The designer receives record drawings from the client; The designer receives geometry records from the client; The designer issues the outline design (i.e. a design which shows principles) to the client; The designer and client agree changes to design to achieve approval or acceptance for the outline design; 6. Steps 4 and 5 are repeated for the detailed design (i.e. one which has all details required for construction); 7. Designer validates the design on site; 8. Designer issues “For Construction” drawings; 9. Installer procures the materials; 10. Installer constructs the design; 11. Installer & Designer create the as fitted records (which detail actual constructed equipment). 7.2
Form EA and Form EB Processes The Form EA and Form EB processes are used in the UK to control OLE designs. The Form EA process controls the production of an outline design. It defines the design outputs, the standards to be met, and the client approval process. The Form EB process works in the same way for a detailed design.
7.3
Design Documentation OLE designs for specific locations are presented in a standardised manner by a series of drawings and documents. This is to ensure that the details are easily understood by any competent person, and that no ambiguity can be present in the design. It should be noted that any proposed alteration to OLE will affect some or all of these drawings. Additionally, many changes to other railway systems have an impact on the OLE drawings. In the UK no written standard for drawing format exists; however there are several examples of industry best practice in circulation. Detail of drawing formats tend to be agreed on a project by project basis, with specific preferences depending on the region or person involved.
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These drawings can be thought of in a hierarchical manner; each drawing overlaps with the one above and below in terms of information. In the following sections this hierarchy is followed in descending order. 7.3.1
Major Feeding Diagram The Major Feeding Diagram (MFD) shows the interface between the supply authority (supply voltage) and the railway (line voltage); feeder stations, TSCs and neutral sections are included.
Figure 83: Typical MFD detail
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7.3.2
Section Diagram and Switching Instructions The section diagrams sit below the MFD and show the detailed electrical feeding & sectioning. They detail switch numbers and locations, booster transformers, and section numbers. These documents are used for taking isolations and are therefore safety critical. These drawings are strictly controlled by the infrastructure owner.
Figure 84: Typical section diagram detail
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Alongside the section diagrams sit the switching instructions. These are a set of procedures detailing the steps to be taken to isolate and earth a particular section. These are also strictly controlled. 7.3.3
Wire Run Diagram The Wire Run Diagram is a schematic showing the wire run numbers, and their anchor locations for a given route.
Figure 85: Typical wire run diagram detail
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7.3.4
OLE Layout Plan The OLE layout plan is the first drawing to show any geometric detail of the OLE. They are typically 1:500 plans of a location, showing OLE structures, wire runs, RCs, earth wires, overlaps, SIs, track curvature, span lengths, height & stagger and other information.
Figure 86: Typical layout plan detail
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7.3.5
OLE Cross Section
Figure 87: Typical cross section detail
The OLE cross section drawing shows detail of a specific cross section across the railway; this will include one or more OLE structures. These drawings are typically 1:100 scale and include all the arrangements, dimensions, and assembly part numbers required to build the structure(s). The assembly part numbers are drawn from the basic design range for the system. The drawing may have more than one sheet – for instance it may be split into support and switching sheets for complex arrangements. 7.3.6
OLE Bridge Drawing The OLE bridge drawing is a set of drawing sheets showing the detail of an overbridge with OLE attachments. These are typically comprised of a layout plan extract, at a larger scale, and a set of cross sections showing the bridge attachments.
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7.3.7
Bonding Plan The bonding plans show the detailed arrangements for the traction earthing and bonding. For the reasons given in section 5.10 they often show signalling bonding as well. These composite bonding plans are generally owned by the signalling discipline, with joint input by signalling and OLE Engineers.
Figure 88: Typical composite bonding plan detail
Composite bonding plans are safety critical and are strictly controlled by the infrastructure owner. 7.3.8
Dropper Tables The dropper tables detail the lengths and positions of droppers for each span length to give the correct profile for the particular equipment type.
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7.3.9
Bill of Quantities The Bill of Quantities (BOQ) is a breakdown of the assemblies shown on the cross sections into components, for use in the procurement of materials.
7.3.10
Overhead System Design The Overhead System Design (OSD) is a document which details the work required for a change to the OLE infrastructure. It typically takes the form of a short description of the work, together with a series of appendices containing all the documents (as detailed above) required to carry out the works.
7.3.11
Testing & Commissioning Plan Where changes are proposed to the feeding, switching and sectioning of OLE, a Testing & Commissioning (T&C) plan is required for the work. This details the steps to be taken to ensure that the system has been installed as per the design; particularly in terms of feeding, switching, sectioning and insulation strength. The T&C plan will detail the tests to be carried out prior to energisation. These tests may include section proving (where each electrical section is tested live and dead in relation to adjoining sections), short circuit testing (where a short circuit is deliberately created to test the fault protection), and any other tests required to prove the safety and operation of the system. The T&C plan should be created in conjunction with the OLE installer so that the logistical requirements may be taken into consideration.
7.3.12
Operation & Maintenance Manuals Where new equipment is introduced to the system as part of a construction activity, a set of Operation and Maintenance (O&M) manuals are required. These give details of the O&M requirements of the new equipment, so that operations and maintenance staff can conduct familiarisation training. In the UK, the O&M requirements for standard types of OLE are detailed in a set of standards documents. Therefore O&M manuals are only required if novel items are introduced in the design.
7.4
Checking Process OLE designs are subject to an internal quality process, to ensure designs are correct and compliant prior to issue to the client. This process is based on the principal of independent checking. This ensures the design is subjected to independent scrutiny prior to issue. There are usually a minimum of three OLE Engineers involved in the process. These are designated as; the designer; the checker; and the approver.
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The designer is the Engineer who has decided upon the details of the design. It is not the person who has created the drawing; rather the person who determined the content. The designer is the main safeguard against poor designs being issued. Their signature means they take responsibility for the design, and that they believe it meets the RAMS requirements. The checker is the Engineer responsible for ensuring that the design meets the requirements of RAMS. It is essential that the checker has played no direct part in the design prior to the check. The checker must satisfy themselves that the design is correct. Their signature means that the design has been officially checked and is compliant. The approver is the senior Engineer who validates the design process. The approver must satisfy themselves that the internal and external procedures have been followed in the design process, that the design meets all requirements, and that the other staff are competent to carry out their respective roles for that design. Their signature means that the design has been created in accordance with these systems. Each drawing must carry the signature of a designer, checker and approver. It is permitted (though not recommended) for the designer and approver, or the checker and approver, may be the same person. However the designer and checker must always be different. 7.5
Design Licensing This section deals with the requirements of the Network Rail (NR) OLE design licensing regime; it therefore applies only to UK heavy rail. However, many of the principals apply equally to other systems. A design organisation must be licensed by NR before it can design a change, removal or addition to, NR OLE. Similarly the individuals working for the organisation must be licensed at the appropriate level for their part in the design. The design licence therefore has two parts; organisation competences, and individual competences. Potential organisations and individuals are assessed by an OLE Engineer who is independent of OLE design organisations. There are four categories of OLE design which the organisation and individual may be licensed to carry out: • • • •
System design is the matching of mechanical and electrical parameters to a railway performance specification; Basic design is the creation of components and assemblies for a system, together with detailed geometry and load rules; Allocation design is the application of basic design assemblies to a location to meet system design requirements; Construction design is the controlled change to an allocation design during construction.
The individuals in the design organisation may be licensed for each of these categories at designer, checker or approver level. The individual must never carry out duties above their level
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of competence in that category, although they may carry out duties below; e.g. an approver may carry out the role of designer. The only exception to this rule is for trainees; they may act as designer prior to being licensed, with the agreement of the checker and approver.
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7.6
Basic Design Ranges A Basic Design Range is a set of drawings which define the components, materials, and geometry of a given OLE system. Each range may contain one or more types of equipment. The allocation designer applies these to a given location in accordance with the performance requirements of that location.
Figure 89: Typical basic design drawing
The following sections give an overview of the various basic design ranges in use in the UK. Each country will have a set of basic designs in this manner; these are developed appropriate to the technology available at the time and the performance requirements of the system.
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7.6.1
GE/MSW Range The Great Eastern (GE) range was developed by London & North East Railways (LNER) and subsequently BR, and was first installed in 1949 for the electrification of the lines out of Liverpool St at 1500V DC. It was then used on the Manchester to Sheffield (via Wath) (MSW) route in 1954. The range was updated to reflect the conversion of GE lines to 6.25kV, and the subsequent conversion of both GE and the remaining section of MSW to 25kV AC. The range is imperial and robustly engineered, using large quantities of Copper (which was a cheap material at the time). The range uses painted steel fabricated portals and planted masts, meaning a large amount of work was carried out on site. Most structures are MIR type, with spanwire portals used in complex areas and sidings. The system has a large quantity of fixed termination equipment, as well as auto tensioned equipment for higher speeds. The contact wire, auxiliary and catenary are of a very large cross section, reflecting the original requirement to carry DC currents; this, coupled with the low tension, means system heights are large. The insulation has been upgraded to 25kV standards.
Figure 90: GE OLE; Stratford, UK
The range is no longer available for design use; however it is used as a reference, since the lines out of Liverpool St and from Ardwick to Glossop still use the range.
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7.7
Mark 1 Range The Mark 1 range was developed by BR and Balfour Beatty in the early 1960s for the first phase of WCML electrification, and consists of approximately 4000 drawings. Like the GE range, the assemblies are imperial and use Copper. The range also uses painted steel fabricated portals and planted masts. All structures are MIR type, with catenary pulleys. Again, system heights are large (1980mm).
Figure 91: Mark 1 portal; Norton Bridge, UK
The range is no longer available for design use; however it is used as a reference, since the southern half of WCML and some other lines still use the range.
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7.7.1
OLEMI Range The OLE Master Index (OLEMI) was initiated in the early 1970s in response to the requirement for cheaper OLE builds; it is still being added to today. It was developed by BR and is now owned by NR; it consists of approximately 11000 drawings. The OLEMI was developed as a modular system, where a single component can carry out many tasks. It is a metric system, and was initially developed with mechanically dependent supports in the form of headspans. MIR assemblies have since been added to the range. The OLEMI maximises the use of galvanised steel, at the expense of Copper, since prices had risen steeply by the 1970s. The range contains the Mark 3, Mark 3a, Mark 3b, Mark 4 and Mark 5 ranges, and some metric conversion assemblies for Mark 1. The use of bolted base masts was pioneered, to help speed up construction. OLEMI schemes include the second phase of WCML electrification, the ECML and the MML. In an effort to reduce structural steelwork, the standard system height is reduced (as far as 900mm for Mark 3b).
Figure 92: APT under Mark 3a headspans; Winwick Jct, WCML UK
The OLEMI is available for use in designs; it is mature, and subject to update every couple of years.
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7.7.2
UK1 Range The UK1 range was developed in the late 1990s in response to the requirement under West Coast Route Modernisation (WCRM) to raise WCML linespeeds. The existing Mark 1 and Mark 3a equipments were not adequate for these speeds; therefore an upgrade range was required. The range covers upgrade of equipment to both 200 and 225kph, although only the 200kph upgrade has subsequently been implemented. The range was developed by the OLE Alliance and consists of approximately 2000 drawings. Although the numbering of the range is designed to integrate with the OLEMI, and the range uses many OLEMI components, it is not currently part of the OLEMI. The range is modular, using a significant amount of Copper (which at this time was cheap again), alongside many aluminium MIR assemblies from continental best practise. It is used at existing Mk1/Mk3a locations and for new schemes. The range is now mature; and is subject to occasional updates.
Figure 93: UK1 overlap portals; Millmeece, UK
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7.7.3
Auto Transformer Range The Auto Transformer range is the newest in the UK; it was started around 2000. It is designed for the ATx feeding pilot scheme under way as part of WCRM and is being developed by NR. It is very immature, and has only recently been approved for use. It is subject to regular updates.
Figure 94: Auxiliary Feeder on CTRL section 1; Ashford, UK
7.7.4
Other Assemblies A number of other arrangements exist in the UK, which have not been included in an approved design range, and a therefore not officially available for new use. For instance, under the Euston Remodelling contract on WCRM new Mk1 FT assemblies were introduced; these are not part of OLEMI or UK1.
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7.8
Construction Methodology It is important to consider the construction of OLE at the planning and design stages. Construction is by far the most costly part of the process. Efficient working will only be possible if the design is matched to the site constraints, and the labour, materials and plant to be used.
The sequence for installation of OLE is generally as follows; • • • • • • • • • • • •
Foundation installation; Mast steelwork erection; Boom steelwork erection; Dress steelwork (add support fittings); Installation of support and registration (also known as Small Part Steelwork or SPS) assemblies; Running out of wiring; Registration of wiring; Switching and feeding connections; Final wiring adjustment; Pantograph running check (panning); Electrical section proving; Energisation.
Figure 95: OLE construction; Temple Mills, UK
Any feeder station works may be carried out in parallel with the OLE works, with connections made near the end of the process. Particular items that should be considered during design are; • • • • • • • • •
Foundation methodology; Site stores for materials; Materials lead times; Concrete availability and curing time; Site access for labour, plant and materials; Crane access and ground stability; Railway closure (possession) requirements; OLE isolation & earthing requirements; Conflict with other works, e.g. permanent way, civil, signalling.
Construction often takes place on an operational railway; in this case, closure and isolation opportunities may be infrequent and short in duration. The design must be staged to take
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advantage of these opportunities, with as much preparation work as possible carried out with trains running. It is important that the designer is involved with the construction phase of the work. It is rare that an OLE design is installed without any changes being required; often as a result of unrecorded buried services, entailing the moving of a structure from its design position. It is essential that this design change is done by a controlled process known as Construction Design (see section 7.5). Broadly, the process is; • • • • • • 7.9
A competent OLE Site Engineer identifies a need for a change to the design; The Site Engineer sends the design change proposal to the design office; The design office Engineer reviews the design change proposal; The design office Engineer amends the proposal as necessary and sends a Design Change Note (DCN) to the site; The design change is made on site; The drawings changed and issued from design office to reflect the new design.
OLE Maintenance It is important to consider the maintainability of OLE at the planning and design stages. OLE is relatively maintenance-free compared with other railway systems. OLE is usually inspected periodically; maintenance is carried out by small teams working from rail-mounted scissor lift platforms.
Figure 96: OLE Maintenance; Stafford, UK
Regular maintenance items are: • •
Checking and cleaning insulators; Checking and adjusting height and stagger;
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• • •
Greasing connections; Structure painting (for older non-galvanised structures); Checking contact wire wear.
More onerous rectification work is required after a dewirement. The team will be required to bring the OLE back into service as quickly as possible, and new wiring and support assemblies may be required. Each area will have a store of materials held against such incidents.
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7.10
Types of UK Equipment There are approximately 60 different types and subtypes of OLE present in the UK, including tram and light rail systems. The type refers to the generic system, e.g. Mark 1 or Mark 3b. The subtype refers to the suspension and tensioning system, and the tensions in each wire. A type may have many subtypes; e.g. Mark 1 has simple and compound, auto-tensioned and fixed termination. The complete list of OLE types in the UK can be found in APPENDIX II. Care must be taken when modifying existing equipment, to determine the type in use and ensure that the basic design range is available.
7.11
Interfaces with Other Subsystems OLE interfaces with almost every other railway subsystem. It is often at the interfaces that design mistakes are made; for this reason it is vital the these are fully considered in the design process. The key interface issues to be considered during OLE design are discussed below.
7.11.1
Permanent Way This is the one of the most important interfaces; the OLE must follow track geometry. Particular items are: • • • • •
7.11.2
Track position; Track lift; Track slew; Change of cant; Position of toes of points.
Civil & Structural Key civil and structural issues to be considered are: • • •
7.11.3
Electrical clearances to structures; Attachment to structures; Foundations.
Signalling Key signalling interfaces are; • • • •
7.11.4
Electrical clearances to signalling structures (RCs, OLE, pan); Signal positions with respect to overlaps and neutral sections; Conflicts with minimum signal sighting distances due to OLE ‘clutter’; Earthing & bonding.
Telecomms The key telecomms interfaces are:
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• •
Electromagnetic Interference (EMI); SCADA.
7.11.5 Electrical & Mechanical Services Electrical & Mechanical (E&M) Services include all non-electrification power supplies, as well as water courses, drainage, water and gas services. The key interfaces are: • • • • • • 7.11.6
Signalling Supply Points (SSPs – a backup feed from OLE for signalling systems); Earthing & bonding; Overhead power cables; Gas & water pipes; Buried power cables; Telecomms cables.
Operations Operations requirements are determined in terms of: • • • • •
7.11.7
Pantograph interface; Reliability; Availability; Maintainability; Safety.
Highways The key interface with highways is at level crossings.
7.11.8
Environment Environmental interfaces include: • • •
Visual impact; Construction impact; Safety impact.
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APPENDIX I - UK OLE Structure Codes
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C C CC CE CH CR ? ? ? ?
Bethnal Green - Cambridge inc Stansted Spur Cambridge - Lincoln - "North" Bury St Junction - Cheshunt Hackney Downs - Enfield Town Clapton Junction - Chingford Broxbourne Junction - Hertford East South Tottenham East Junction - South Tottenham West Junction South Tottenham West Junction - Seven Sisters Junction Woodgrange Park Junction - start of line to Gospel Oak Reading Lane Junction - Navarino Road Junction
AC MA MH SB
Castlefield Junction - Trafford Park Manchester Oxford Road - Altrincham Ardwick - Hadfield Stockport - Hazel Grove
AL D DA DB DW HP PD PT SA SAO
Aston - Lichfield Kings Norton - Barnt Green Barnt Green - Redditch Birmingham New St - Kings Norton Pleck Junction - Walsall Bescot - Pleck Junction (may be BP) Pleck Junction - Darlaston Junction Wolverhampton - Portobello Junction Stetchford - Aston Wolverhampton - Stetchley
WA
UK Equipment Information.xls
Unsure
London Liverpool St - Norwich (code not shown on structures between Liverpool St approach and Arbour Lane, Chelmsford Witham - Braintree Colchester - Clacton Stratford Central Junction - Carpenters Rd N Jct Manningtree N Jct - Manningtree - E Jct Manningtree S Jct - Ipswich Romford - Upminster Norwich Thorpe Junction - Crown Point Depot East Gate Junction - Colchester Town Gas Factory Jct - Bow Jct Forest Gate - Barking Ilford Carriage Sheds Hythe Junction - Colchester Town Shenfield flyunder (LNER code still used) Colchester flyunder (LNER code still used) Shenfield - Southend (LNER code still used) Stratford Central Junction - Coppermill Jct Thornton Fields Sidings Thorpe le Soken - Walton on Naze Carpenters Rd S Jct - Carpenters Road N Jct Channelsea North Junction - Temple Mills East Junction Wickford - Southminster
Not Used
Code B BB BC BM BE BH BU BY EB F FB IL HL L L S SC TH TW V ? SS
Line Closed
Abbrev
London Fenchurch St - Shoeburyness Barking - Pitsea via Grays Gas Factory Jct - Bow Jct (few masts only) Woodgrange Park - Gospel Oak (few masts only) Tilbury Freightliner Yard Upminster - Grays
GE
LTS
Birmingham Suburban
Manchester Suburban
A AT AB TH TF UG
N/A
West Anglia
Great Eastern
London, Tilbury & Southend
Area
N/A
Common Name
Railway Electrification Engineering Introduction to Overhead Line Electrification
y
y
y y y y
y
13/08/2008
BB BB BS CB CM CN CS EN F G GC GB GL GM HC HH KC KC L LL LM M MAS NC NW PB RR SG SO SW V WL WS ?
Birmingham New St - Bushbury Junction (via Wolverhampton) Dalreoch - Balloch Pier Birmingham New St - Stafford (vie Aston/Bescot) Carnforth (start of Barrow branch) Cheadle Hulme - Macclesfield Coventry - Nuneaton Crewe - Gresty Lane (Shrewsbury line) Norton Bridge - Stone Denbigh Hall South Junction - Bletchley flyover Euston - Law Junction (or Eglinton St) Crewe - Steelworks Junction (Chester line) Rugby - Birmingham New St Weaver Junction - Liverpool Lime St (first few masts, see also L) Crewe - Manchester Oxford Road (first few masts, see also M) Macclesfield Hibel Road - Colwich Hartford LNW Junction - CLC Junction Coventry - Park Junction (Kenilworth line) Kidsgrove - Crewe Weaver Junction - Liverpool Lime St (see also GL) Crewe Low Level lines Edge Hill - Olive Mount Junction, and Earlestown - Newton le Willows Junction Crewe - Manchester Oxford Road (see also GM) Manchester Airport south curve Short section at Carlisle end of Newcastle - Carlisle line Nuneaton - Abbey Junction Preston - start of Blackpool line Roade - Rugby via Northampton Speke - Garston Wilmslow - Slade Lane Junction Stafford headshunt (former Wellington line) Carpenters Road South Junction - Primrose Hill Junction (North London Line) North end of West London Line Wolverhampton North Junction - Oxley Carriage Sidings Manchester Airport branch
UK Equipment Information.xls
Unsure
Glasgow High St - Helensburgh Central via Singer Hyndland depot branch Westerton - Milngavie Singer Works branch Hyndland East Junction - Dalmuir via Yoker Glasgow High Street - Drumgelloch Glasgow High St - Bridgeton Central Bellgrove - Springburn Glasgow Central - Eglinton St; Rutherglen - Carstairs Cathcart Circle Motherwell - Coatbridge Newton - Motherwell via Hamilton Loop Cathcart - Neilston Cathcart - Newton Lanark branch Glasgow Central - Gourock Paisley - Ayr Largs branch Shields Jct - Corkerhill Depot Ardrossan Harbour branch Bogston - Wemyss Bay Finnieston E Jct - Rutherglen
Not Used
Code
N/A
B BH BM BS BY F FB FS G GC GD GH GJ GK GS L LA LB LC LN LW RF
Line Closed
Abbrev
Area
WCML
West Coast Mainline
Glasgow Suburban
Common Name
Railway Electrification Engineering Introduction to Overhead Line Electrification
y y
y
y
y
y
y
y y y y
y y
13/08/2008
MML
F MF
N/A
H J
Paddington lines
Channel Tunnel Rail Link
Marylebone
St Pancras - Bedford Kentish Town - Moorgate Paddington - High Wycombe Paddington - Heathrow
Y Y YA YW ?
St Pancras - Channel Tunnel boundary Channel Tunnel boundary - Dollands Moor - Saltwood Tunnel (code now changed, see below) Ashford station loop of Channel Tunnel Rail Link Singlewell Junction - end of OLE near Fawkham Junction Channel Tunnel boundary - Dollands Moor - Saltwood Tunnel (code was Y, now Y "something")
D
Marylebone lines
N/A
UK Equipment Information.xls
Unsure
Midland Mainline
Not Used
Code
Apperley Junction - Ilkley Kings Cross - Haymarket East Junction Doncaster - Leeds - Neville Hill Depot Hitchin - Shepreth Hertford Loop Start of Doncaster - Hull line Portobello Junction - Newcraighall (thence to Millerhill Yard?) York avoiding line Drem - North Berwick Whitehall Junction - Copley Hill West Junction Leeds - Skipton Shipley - Bradford Forster Square Shipley - Guiseley Shipley West Curve Finsbury Park - Drayton Park Finsbury Park - Canonbury Whitehall Junction - Engine Shed Junction Leeds West Junction - Engine Shed Junction Newcastle southern loop through Gateshead
Line Closed
Abbrev ECML
AY E EB EC EH ET EW EXG EZ LH LS SB SG SW ? ? ? ? ?
CTRL
Area
East Coast Mainline
Common Name
Railway Electrification Engineering Introduction to Overhead Line Electrification
y
y
y y y y y y y y
y
y
13/08/2008
Railway Electrification & Power Engineering REPE Handbook: Introduction to Overhead Line Electrification
APPENDIX II - UK OLE Types and Subtypes
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13/08/2008
UK OLE Types
4 5 6 7 8 9 10 11
Great Eastern (GE) & 12 Manchester - Sheffield - Wath (MSW)
Simple
FT
193 Cu-Cd
13350
3000
2730
-
-
?
50
80
Simple
FT
107 Cu-Cd
7565
1700
6075
1365
-
-
-
?
45
72
SCS 02 - orig. reduced tension Simple FT ¥ 1st Section > Last Section >
Simple
FT
193 Cu-Cd 2x107 Cu-Cd
13350 6675
3000 1500
37/2.4 HDCu 19/2.1 Cu-Cd (was HDCu) 37/2.4 HDCu 2x19/2.1 Cu-Cd
12150
SCS 01 - orig. Sidings Simple FT
12150 6075
2730 1365
-
-
?
45
72
SCS 03 - ML Compound AT ¢
Compound
AT
193 Cu-Cd
13350
3000
37/2.4 HDCu ¢
13885
3120
5355
1203
?
80
128
SCS Tramway GE/MSW 00 - orig. ML Compound FT GE/MSW 04 - orig. Tramway FT GE 00 - orig. RML Simple FT GE 01 - orig. Sidings Simple FT GE 03 - reduced tension Simple FT ¥ 1st Section > Last Section > GE 03 - reduced tension Tramway FT ¥ 1st Section > Last Section >
Tramway Compound Tramway Simple Simple
? FT FT FT FT
? 193 Cu-Cd 193 Cu-Cd 193 Cu-Cd 193 Cu-Cd 193 Cu-Cd 2x107 Cu-Cd 193 Cu-Cd 2x107 Cu-Cd
? 13350 13350 13350 13350 13350 6675 13350 6675
? 3000 3000 3000 3000 3000 1500 3000 1500
37/2.64 HDCu 37/2.64 HDCu 7/3.63 Cu-Cd 37/2.64 HDCu 2x19/2.1 Cu-Cd -
16955 16955 8850 16955 6675 -
3810 3810 1988 3810 1500 -
19/2.1 Cu-Cd (was HDCu) 19/2.85 HDCu -
5674 -
1275 -
? ? ?
42 80 25 50 41
65 128 40 80 65
13350
3000
?
?
?
-
-
13350 13350
3000 3000
? 19/2.85 HDCu
10280 14462
2310 3250
-
-
13350
3000
37/2.64 HDCu
16955
3810
-
8900 11300 8900 11300 9900 11300 11900 14000 8900 ? ? ? 8900 9900 8925 11180 11180 8925 11160 11000 8630 11200
2000 2539 2000 2539 2224 2539 2674 3146 2000 ? ? ? 2000 2224 2005 2512 2512 2005 2507 2472 1939 2516 0 0 0 2472 2516 2539 2472 2472 ? ? ? ? 4045 4494 0 0 4494 ? ? ? ?
19/2.1 Cu-Cd 19/2.1 Cu-Cd 19/2.1 Cu-Cd 19/2.1 Cu-Cd 19/2.1 Cu-Cd 19/2.1 Cu-Cd 19/2.1 Cu-Cd Cu-Cd 19/2.1 Cu-Mg 19/2.1 Cu-Mg 19/2.1 Cu-Mg 19/2.1 HDCu 19/2.1 HDCu 19/2.1 HDCu 19/2.1 HDCu 7/3.95 AWAC 7/3.95 AWAC 7/3.95 AWAC 7/3.95 AWAC 19/2.1 Cu-Cd 19/2.1 Cu-Cd 7/3.95 AWAC 7/3.95 AWAC 19/2.1 HDCu 19/2.1 Bronze 19/2.1 Cu-Mg 19/2.1 Cu-Mg 19/2.1 Cu-Mg 7/3.95 AWAC 19/3.39 AWAC 37/2.5 HDCu 19/2.1 Cu-Cd 19/2.1 Cu-Cd 37/1.5 Bronze ? ? -
8180 8560 8180 8180 8180 8560 8560 8180 ? ? ? 8180 8180 11100 8630 11100 11160 11000 11200 -
1838 1923 1838 1838 1838 1923 1923 1838 ? ? ? 1838 1838 2494 1939 2494 2507 2472 2516 0 0 2472 1939 2472 2472 ? ? ? ? 5393 4494 0 0 3146 ? ? -
7/2.1 Cu-Cd 7/2.1 Cu-Cd Cu-Cd 19/3.39 AWAC -
Simple
FT
Tramway
FT
Simple
GE 07 - RML(light) Simple FT MSW 02 - orig. RML(light) Simple FT
Simple Simple
16
MSW 05 - orig. RML(heavy) Simple semi-AT
Simple
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73
Compound AT Compound AT (supertensioned) Simple AT Simple AT (supertensioned) Simple FT Tramway Sagged Simple AT UK1 upgrade (for 200kph) Sagged Simple AT UK1 upgrade (for 225kph) Stitched Simple AT All Areas of heavy electrical load Areas of high pan passages Sagged Simple AT Simple FT Sagged Simple AT Simple FT Tramway Sagged Simple AT Sagged Simple AT (supertensioned) Sagged Simple AT (Mk3b tensions) Simple FT Tramway FT Tramway AT? Sagged Simple AT UK1 upgrade (for 200kph) Sagged Simple AT UK1 upgrade (for 225kph) Sagged Simple AT Simple FT Tramway FT Sagged Simple AT Sagged Simple AT All Areas of heavy electrical load Areas of high pan passages Areas with AWAC catenary Compound AT Simple AT Sagged Simple AT (for 200kph) Sagged Simple AT (for 225kph) Sagged Simple AT ? Simple AT Tramway AT (double CW) Tramway AT (single CW)
Compound Compound Simple Simple Simple Tramway Sagged Simple Sagged Simple Stitched Simple All All Simple Sagged Simple Simple Sagged Simple Simple Tramway Sagged Simple Sagged Simple Sagged Simple Simple Tramway Tramway Sagged Simple Sagged Simple Sagged Simple Simple Tramway Sagged Simple Sagged Simple All All Simple Simple Compound Simple Sagged Simple Sagged Simple Sagged Simple ? Simple Tramway Tramway Tramway Simple Simple Tramway Tramway Tramway Tramway Simple Tramway ? Simple Simple Tramway Tramway
Mark 3
Mark 3a
Mark 3b Mark 3c Mark 3d Mark 3/3a/3b/3c proposed upgrade Mark 4 Mark 5 UK1 standalone CTRL Brown Boveri Tyne & Wear Metro Croydon Tramlink Midland Metro Manchester Metrolink
Sheffield Supertram Nottingham Express Transit Blackpool Tram Leeds Supertram Channel Tunnel SICAT medium speed Luas Tram AT Luas Tram FT
Simple AT MJSA (Mark 3 Simple FT converted from Mark 1) Tramway FT Reduced Tension Tramway FT Tramway Simple
Simple AT Simple AT Tramway AT Tramway FT
* Spring Tensioned § Cantilever/Headspan ¥ one heavy wire run splitting to two light wire runs ¢ Catenary tension lengths longer than aux/cw tension lengths - typically, one cat covers 3 aux/cws ML = mainline RML = reduced mainline
FT cat 193 Cu-Cd AT cw FT 193 Cu-Cd FT 193 Cu-Cd AT cat* 193 Cu-Cd FT cw AT 107 Cu-Cd AT 107 Cu-Cd AT 107 Cu-Cd AT 107 Cu-Cd FT 107 Cu-Cd FT? 107 Cu-Cd AT 120 Cu-Ag AT 120 Cu-Ag AT Cu-Cd All 107 Cu-Sn All 107 Cu-Ag FT 107 Cu-Mg AT 107 HDCu FT 107 Cu-Cd AT 107 HDCu FT 107 Cu-Cd FT? 107 Cu-Cd? AT 107 HDCu AT 107 HDCu AT 107 HDCu FT 107 Cu-Cd FT 107 Cu-Cd AT AT 120 Cu-Ag AT 120 Cu-Ag AT 107 HDCu FT 107 Cu-Cd FT 107 Cu-Cd AT 107 HDCu AT 107 Cu-Sn (0.4) All 107 Cu-Sn All 107 Cu-Ag FT 107 Cu-Mg All 107 HDCu AT 107 Cu-Cd AT 150 HDCu AT 120 Cu-Ag AT 120 Cu-Ag AT 150 HDCu ? ? AT ? AT twin AT single AT FT FT FT ? ? ? ? ? AT AT AT FT
120 HDCu 107 Cu-Cd 2 x 120 Cu-Cd 2 x 120 Cu-Cd ? ? ? ? ? ? 107 Cu-Ag 120 HDCu 120 HDCu
11000 11200 11300 11000 11000 ? ? ? ? 18000 20000
20000 ? ? ? ? 12000 12092 12000 24000 ? ? ? ? ? ? 11230 12000 12000
2696 2717 2696 5393 ? ? ? ? ? ? 2523 2696 2696
N/A
N/A N/A
N/A Yes Yes
Yes Yes N/A Yes Yes Yes N/A N/A Yes Yes Yes N/A Yes Yes
Yes Yes Yes Yes
N/A N/A No No N/A N/A
-
2 x 19/2.8 HDCu 19/2.1 HDCu ? ? ? 19/2.1 Cu-Bronze -
11000 8630 11000 11000 ? ? ? ? 24000 20000
14000 ? ? 12000 8612 ? ? ? 11230 -
2696 1935 ? ? ? 2523 -
-
N
lb
5355
1203
41
65
-
41
65
-
?
97
155
-
? ?
41 41
65 65
-
-
?
80
128
3000 3000 1510 11000 -
674 674 339 2472 -
100 100 60? ? 60 20 125 140 ?
160 160 ? ? 95 30 200 225 ?
-
1 of 1
-
?
1980
1980
Designer
?
1956
1500V DC
? ?
1400
1400 900/1400§ 1400 900/1400§ 900/1400§ All All All All 1100-1400 ?
1400 ? ? ? 1400 ? ? ? 1200 -
100 60 110 64 20 110 ? ? 60 25 ? 125 140 125 60 25 125 125
160 95 175 100 30 175 ? ? 95 40 ? 200 225 200 95 40 200 200
155 ? 125 140 189 ? ? 50 50 45 50 64 30 30 ? ? 50 ? ? 100 100 45 ?
245 ? 200 225 300 ? ? 80 80 70 80 100 45 45 ? ? 80 ? ? 160 160 70 ?
1979
25kV AC
Locations
UK / Network Shenfield - Witham; Shenfield - Southend Rail
Liverpool St - Shenfield; Christian St Jct - Gas Factory Jct; Manchester - Sheffield (via Wath - now curtailed to Ardwick - Hadfield)
?
1949 (GE) 1500V DC 1952 (MSW)
1960 (GE 6.25kV AC only)
1976 1987 (GE) 25kV AC 1984 (MSW)
Liverpool St - Shenfield; Christian St Jct - Gas Factory Jct; UK / Network Rail
Gas Factory Jct - Bow Jct Manchester - Sheffield (via Wath - now curtailed to Ardwick - Hadfield)
BICC
1957 ? 1957 ? 1957 1957 2000 not used 1957
1980
1400
1960 6.25kV AC 1962
Country / Administration
SCS 00 - orig. RML Simple FT
19/2.1 Cu-Cd (was HDCu) -
Conversion Voltage
3120
Conversion Date
13885
Conversion Voltage
37/2.4 HDCu ¢
Conversion Date
3000
GE 06 - RML(heavy) Simple semi-AT
Mark 2
System Height
lb
13350
N/A
Cross Section (mm²) & Material
N
193 Cu-Cd
Presag?
lb
FT
14 15
Mark 1 proposed upgrade
128
N
Compound
13
Mark 1
kph
80
Suspension
SCS 00 - orig. ML Compound FT ¢
Build Voltage
Shenfield - Chelmsford Southend (SCS)
mph
?
Subtype
Build Date
3
Linespeed
Cross Section (mm²) & Material
2
Aux. Catenary or Stitch Wire Tension (10°C)
Cross Section (mm²) & Material
Type 1
Catenary Tension (10°C)
Tensioning
Contact Wire Tension (10°C)
25kV AC
-
-
-
-
25kV AC
-
-
-
-
London Euston - Weaver Jct; Crewe - Liverpool; Colwich - Manchester; Crewe Manchester; Rugby - Stafford via Birmingham; Roade - Rugby via Northampton; UK / Glasgow suburban stage 1; Christian St Jct - Shoeburyness; Barking - Pitsea via Network Grays; Chelmsford - Colchester; Colchester - Clacton & Walton; Bethnal Green Rail Bishop's Stortford, Hertford East, Enfield & Chingford;
UK / Network Rail UK / Network Rail UK / Network Rail
All installed equipment now removed Not Installed Not Installed Not Installed Glasgow - Wemyss Bay; Glasgow - Gourock (Glasgow suburban stage 2)
?
1966
25kV AC
-
-
-
-
British Rail/BICC
1968
25kV AC
-
-
-
-
25kV AC
-
-
-
-
UK / Network Rail
St Pancras - Bedford; Hitchin - Edinburgh; Doncaster - Leeds; Leeds - Ilkley, Skipton & UK / Bradford; Carstairs - Edinburgh; Bishop's Stortford - King's Lynn, Royston & Stansted; Network Colchester - Norwich & Harwich; Romford - Upminster; Wickford - Southminster; Paisley Rail Ayr & Largs; West London Line
1972 British Rail/BICC
2000 not used 1978
25kV AC
-
-
-
-
British Rail Network Rail
1980 2005 not used not used not used not used not used 1992 2003 2003 1961 1980 2000 2000 1999 1992 1931 1992 1992 1994
25kV AC 25kV AC
-
-
-
-
Balfour Beatty/WS Atkins Amec Spie Brown Boveri ? ? ? Balfour Beatty BICC/Balfour Beatty Conversion Balfour Beatty Balfour Beatty ? ? ? ? ? Balfour Beatty Siemens Brecknell Willis
2004 1898 1994 2005 2004 2004
Weaver Jct - Glasgow; King's Cross - Royston & Hertford Loop; Witham - Braintree
King's Lynn sidings Weaver Jct - Glasgow
British Rail
Balfour Beatty British Rail
Clapton - Cheshunt (Lea Valley);
25kV AC
-
-
-
-
25kV AC 25kV AC 25kV AC 25kV AC ±25kV AC 6.25kV AC 1500V DC 750V DC 750V DC 750V DC 750V DC 1500V DC 750V DC 750V DC 750V DC 750V DC 750V DC 660V DC 750V DC 25kV AC 25kV AC 750V DC 750V DC
1979 1971 -
25kV AC 25kV AC -
1992 -
750V DC -
-
-
-
-
UK / NR Stockport - Hazel Grove; London Fenchurch St - Christian St Jct UK / NR On trial between Claypole & North Muskham Not Installed UK / Not Installed Network Not Installed Rail Not Installed UK / NR Not installed (developed for West Coast upgrade for APT?) UK / NR Dollands Moor Yard Network Crewe - Kidsgrove; Old Dalby Test Track Not installed Rail UK / NR Fawkenham Jct - St Pancras International UK / NR Cathcart W Jct - Neilston UK / NR Tyne & Wear suburban lines UK / TfL Croydon - New Addington, Wimbledon, Beckenham Jct & Elmers End UK
UK
Birmingham Snow Hill - Wolverhampton Mancester Victoria - Bury; Cornbrook Junction - G-Mex Cornbrook Jct - Altrincham Manchester City Centre (small radius curves) Manchester City Centre Sheffield - Meadowhall, Halfway, Herdings Park, Malin Bridge & Middlewood
UK
Nottingham - Phoenix Park & Hucknall
UK
UK UK UK/France UK Ireland
Blackpool Seafront Under Construction Cheriton - Frethun (France) Haughhead - Larkhall, Shields - Gourock Dublin City Centre Dublin Connolly - Tallaght, St.Stephen’s Green - Sandyford
13/08/2008
Railway Electrification & Power Engineering REPE Handbook: Introduction to Overhead Line Electrification
APPENDIX III - UK OLE Build History
Page 129
August 2008
Railway Electrification Engineering Introduction to Overhead Line Electrification
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UK Equipment Information.xls
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
Side
Centre
Side
Bottom
4th
Electric Traction Equipment Type Contact Position Top
Finish
3rd
Start
OLE
Date Type
9 9 9 9 9 9 9 9 9 9 9 9
9
9 9
9 9 9
9 9 9 9
Voltage From
To
Route
Route Designation
-
500V DC
Stockwell - King William Street
525V DC
Alexandra Dock - Herculaneum Dock
City & South London Railway (now part of Northern Line) Liverpool Overhead Railway
-
525V DC
Alexandra Dock - Seaforth Sands
Liverpool Overhead Railway
-
525V DC
Herculaneum Dock - Dingle
Liverpool Overhead Railway
-
520V DC
London Waterloo - Bank
Waterloo & City Line
-
660V DC
Gynn - Fleetwood
Blackpool Tram
-
?
Earl's Court - High St Kensington
District Line
-
550V DC
?
Central London Railway LUL Central Line
-
550V DC
Shepherds Bush - Bank
9 9 9 9 9 9 9 9 9 9 9
-
630V DC
Earls Court - High Street Kensington
LUL District Line
-
630V DC
Borough - Moorgate
LUL Northern Line
-
630V DC
Stockwell - Clapham Common
LUL Northern Line
-
630V DC
Moorgate - Angel
LUL Northern Line
-
650V DC
Liverpool Central - Birkenhead & Rock Ferry
-
630V DC
Acton Town - Park Royal
LUL District Line
-
630V DC
Park Royal - South Harrow
LUL District Line
-
630V DC
Ealing - South Harrow
LUL District Line
-
630V DC
Liverpool Exchange - Southport
-
630V DC
Southport - Crossens
-
600V DC
New Bridge St - Newcastle Central; Percy Main - Manors South; Manors East - Trafalgar Yard; Heaton South Jct - Benton Quarry Jct
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
-
525V DC
Seaforth Sands - Seaforth & Litherland
Liverpool Overhead Railway
-
630V DC
Hounslow West - South Acton
LUL District Line
-
630V DC
Ealing Broadway - Whitechapel
LUL District Line
-
630V DC
Putney Bridge - High Street Kensington
LUL District Line
-
630V DC
Turnham Green - Richmond
LUL District Line
-
630V DC
Whitechapel - East Ham
LUL District Line
-
630V DC
Putney Bridge - Wimbledon
LUL District Line
-
630V DC
Baker Street - Uxbridge
LUL Metropolitan Line
-
630V DC
Inner Circle
LUL Metropolitan Line
-
630V DC
Marsh Lane - Aintree
-
630V DC
Sandhills - Aintree
-
660 V DC
Lambeth North - Baker Street
-
660 V DC
Lambeth North - Elephant & Castle
LUL Bakerloo Line
-
630V DC
Hammersmith - Edgware Road
LUL Metropolitan Line
-
630V DC
Latimer Road - Addison Road
LUL Metropolitan Line
-
630V DC
Hammersmith - Finsbury Park
LUL Piccadilly Line
-
660 V DC
Baker Street - Marylebone
LUL Bakerloo Line
-
660 V DC
Marylebone - Edgeware Road
LUL Bakerloo Line
-
630V DC
Angel - Euston
LUL Northern Line
-
630V DC
Strand - Golders Green / Archway
LUL Northern Line
-
630V DC
Holborn - Aldwych
LUL Piccadilly Line
-
550 V DC
Shepherds Bush - Wood Lane
LUL Central Line
-
630V DC
East Ham - Barking
LUL District Line
-
6.7kV 50Hz AC
Lancaster - Morecambe - Heysham
L&YR
-
6.7kV 50Hz AC
London Victoria - London Bridge via Denmark Hill
LB&SCR
9
9 9
LUL Bakerloo Line
9 9 9
9 9 9
9 9 9
-
630V DC
Aintree - Maghull
-
630V DC
Southport - Crossens via Meols Cop
-
600V DC
New Bridge St - Newcastle Central; Percy Main - Manors South; Manors East - Trafalgar Yard; Heaton South Jct - Benton Quarry Jct
9
9
9
-
630V DC
South Harrow - Rayners Lane
LUL District Line
-
6.7kV 50Hz AC
Battersea Park - Crystal Palace via Streatham Hill
LB&SCR
-
630V DC
Maghull - Town Green
-
500V DC
Grimsby (Corporation Bridge) - Immingham Town
Grimsby & Immingham Railway
-
550 V DC
Bank - Liverpool Street
LUL Central Line
-
6.7kV 50Hz AC
LB&SCR
-
500V DC
Peckham Rye - Streatham Hill; Peckham Rye - Crystal Palace Low Level via Tulse Hill Immingham Town - Immingham Dock
-
630V DC
Town Green - Ormskirk
-
660 V DC
Edgeware Road - Paddington
LUL Bakerloo Line
-
630V DC
Shoreditch - New Cross/New Cross Gate
LUL Metropolitan Line
-
630V DC
St Mary's - Whitechapel Junction
LUL Metropolitan Line
-
3.5kV DC
Bury - Holcombe Brook
L&YR
-
630V DC
Earls Court - Addison Road
LUL District Line
-
660V DC
London Waterloo - East Putney via Clapham Jn
-
500V DC
Immingham Town - Immingham Queens Bridge
Grimsby & Immingham Railway
-
1.5kV DC
Newport - Shildon Railway
-
660 V DC
Middridge Sidings - Bowesfield; Shildon Yard - Middridge Sidings; Bowesfield - Erimus Yard Paddington - Kilburn Park
-
660 V DC
Kilburn Park - Queens Park
LUL Bakerloo Line
-
660 V DC
Queens Park - Willesden Junction
LUL Bakerloo Line
-
660 V DC
Clapham Jct - Clapham Jct via Kingston
Kingston Loop
-
660 V DC
Strawberry Hill - Shepperton; Fulwell Jct - Shacklegate Jct
-
660 V DC
Barnes - Twickenham via Hounslow
-
660 V DC
New Malden - Hampton Court
-
660 V DC
Surbiton - Claygate
9 9
9
9
9
9
9
9 9 9 9
9 9 9 9
9
9 9
9 9 9 9
9 9 9
9 9
9 9
9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9
9 9
9
9
9 9 9 9
9 9 9
9 9 9
Grimsby & Immingham Railway
LUL Bakerloo Line
Hounslow Loop
1.5kV DC
Erimus Yard - Newport East
-
630V DC
Kensal Green Jct - Willesden Jct
Euston - Croxley Gn
-
1.5kV DC
Newport (nr Newcastle) - Shildon
Newport - Shildon Railway
-
1.2kV DC
Manchester Victoria - Bury
630V DC
London Broad St - Richmond
North London Line
630V DC
Willesden Jct - Watford Jct
Euston - Croxley Gn
-
Newport - Shildon Railway
13/08/2008
Railway Electrification Engineering Introduction to Overhead Line Electrification
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De-electrification
1935
New Build
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UK Equipment Information.xls
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
9
9 9
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
Side
Centre
Side
Bottom
4th
Electric Traction Equipment Type Contact Position Top
Finish
3rd
Start
OLE
Date Type
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
9 9 9
9 9
9 9
9 9
9
Voltage From
To
Route
Route Designation
LUL Bakerloo Line
-
660 V DC
Willesden Junction - Watford Junction
3.5kV DC
1.2kV DC
Bury - Holcombe Brook
-
550 V DC
Wood Lane - Ealing Broadway
LUL Central Line
-
630V DC
London Euston - Queens Park; Colne Jct - Croxley Green
Euston - Croxley Gn
-
660 V DC
London Victoria - Orpington via Herne Hill
-
660 V DC
Holborn Viaduct - Herne Hill via Loughborough Jct
-
660 V DC
Brixton & Loughborough Jct - Shortlands via Catford
-
660 V DC
Nunhead - Crystal Palace High Level
-
660 V DC
Elmers End - Hayes
-
660 V DC
Raynes Park - Dorking North via Leatherhead
-
660 V DC
Claygate - Guildford via Effingham Jct
-
660 V DC
Leatherhead - Effingham Jct
-
660 V DC
London Charing Cross & London Cannon Street - Orpington via
-
660 V DC
Grove Park - Bromley North
-
660 V DC
St Johns - Addiscombe via Catford Bridge
-
660 V DC
North Kent Jct - Dartford via Slade Green
-
660 V DC
Blackheath - Charlton
-
660 V DC
Lewisham - Dartford via Blackheath
-
660 V DC
Hither Green - Dartford via Sidcup
-
660V DC
Rossall
Blackpool Tram
-
630V DC
Harrow on the Hill - Rickmansworth
LUL Metropolitan Line
-
630V DC
Rickmansworth / Moor Park - Watford
LUL Metropolitan Line
-
6.7kV 50Hz AC
Balham - Coulsdon North & Sutton
LB&SCR
Catford Loop
9 9 9
9 9 9
9 9 9
6.7kV 50Hz AC
600V DC
London Victoria - Holborn Viaduct
-
600V DC
Elmers End - Hayes
-
600V DC
London Charing Cross & Cannon Street - Bromley North & Orpington Mid Kent Line
9 9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9 9
-
600V DC
to Dartford
-
630V DC
Croxley Green Jct - Rickmansworth Church Street
-
660 V DC
London Bridge - Purley via East Croydon
-
660 V DC
Purley - Tattenham Corner
-
660 V DC
Purley - Caterham
-
660 V DC
Sydenham - Crystal Palace Low Level
-
660 V DC
Tulse Hill - Sutton via Norwood Jct
-
660 V DC
Sutton - Epsom Downs
6.7kV 50Hz AC
660 V DC
London Victoria - London Bridge via Denmark Hill
6.7kV 50Hz AC
660 V DC
Battersea Park - Crystal Palace
6.7kV 50Hz AC
660 V DC
Crystal Palace - Selhurst
6.7kV 50Hz AC
660 V DC
Peckham Rye - West Norwood
6.7kV 50Hz AC
660 V DC
Tulse Hill - Streatham Hill
-
6.7kV 50Hz AC
Tulse Hill - Streatham Common
LB&SCR
-
6.7kV 50Hz AC
Victoria - Sutton & Coulsdon North
LB&SCR
-
660 V DC
Herne Hill - Tulse Hill
-
660 V DC
Streatham - Wimbledon via Haydon's Road
-
660 V DC
Streatham - Epsom via - Mitcham Jct
-
660 V DC
Crystal Palace Low Level - Norwood Jct
-
660 V DC
Crystal Palace Low Level - Beckenham Jct
-
660 V DC
Wimbledon - South Merton
-
660 V DC
South Merton - Sutton
-
660 V DC
Hounslow Jct - Windsor via Staines; Whitton Jct - Feltham Jct
-
660 V DC
West Croydon - Wimbledon
-
660 V DC
Dartford - Gravesend
-
1.5kV DC
Manchester - Altrincham
-
660 V DC
Purley - Three Bridges via Coulsdon North
-
660 V DC
Coulsdon North - Three Bridges via Redhill
-
660 V DC
Redhill - Reigate
-
630V DC
Barking - Upminster
-
630V DC
Wembley Park - Stanmore
LUL Metropolitan Line
-
630V DC
Hammersmith - South Harow
LUL Piccadilly Line
-
630V DC
Finsbury Park - Arnos Grove
LUL Piccadilly Line
-
630V DC
South Harrow - Rayners Lane
LUL Piccadilly Line
-
660 V DC
Three Bridges - Brighton via Haywards Heath
-
660 V DC
Preston Park - West Worthing via Hove
-
660 V DC
Lewisham - Hither Green
-
660 V DC
Brighton - Hove
-
630V DC
Acton Town - Northfields
LUL Piccadilly Line
-
630V DC
Arnos Grove - Enfield West (now Oakwood)
LUL Piccadilly Line
-
630V DC
Northfields - Hounslow West
LUL Piccadilly Line
-
630V DC
Enfield West - Cockfosters
LUL Piccadilly Line
-
660V DC
Bickley Jct - St Mary Cray
9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9
9 9 9 9 9
9
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9
9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9 9 9 9
1.5kV DC
-
-
660V DC
All NSR lines Chislehurst and Orpington - Sevenoaks
-
660V DC
Brighton - Ore via Hastings
-
660V DC
Wivelsfield - Seaford via Lewes
-
660V DC
Haywards Heath - Horsted Keynes
-
660V DC
Nunhead - Lewisham
-
660V DC
Woodside - Sanderstead
-
660V DC
Additional platforms at London Waterloo
-
660V DC
Staines - Weybridge
-
660V DC
Hampton Court Jn - Guildford via Woking
-
660V DC
Woking - Farnham via Pirbright Jct
-
660V DC
Guildford - Portsmouth Harbour via Haslemere
-
660V DC
Farnham - Alton
Euston - Croxley Gn
MSJ&A Line
LUL District Line
Newport - Shildon Railway
13/08/2008
Railway Electrification Engineering Introduction to Overhead Line Electrification
1939
New Build
1939
New Build
1938
New Build
1938
New Build
1939
New Build
1939
New Build
1939
New Build & Conversion New Build
1940
9
1946
New Build
1947
New Build
1947
New Build
1947
New Build
1947
New Build
1948
New Build
1948
New Build
1948
New Build
1948
New Build
1949
9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9
New Build
1949
New Build
1949
1938 1938
New Build
1938
New Build
1938
New Build
1938
New Build
1939
New Build
1939
New Build
1939
New Build
1939
New Build
1939
New Build Conversion
1952 1951
1953
Closure
1953
New Build
1954
New Build
1955
New Build
1956
New Build
1956
Closure De-electrification
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
1961
New Build
1957
New Build
1958
New Build
1959
New Build
1959
-
9
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9
9 9 9 9 9 9 9 9 9 9
9
9
9 9 9 9 9
1956 1956
From
9 9 9 9 9
9
9
9 9
9
9
9
9 9 9
Conversion
1960
Conversion
1960
New Build
1960
9 9 9
Conversion
1960
9
New Build
1960
New Build
1960
New Build
1960
New Build
Voltage
Side
New Build
New Build New Build
Centre
1939 1939
Finish
Side
New Build New Build
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
Start
Bottom
4th
Top
3rd
Electric Traction Equipment Type Contact Position OLE
Date Type
9
9
To
660V DC
Three Bridges - Horsham
-
660V DC
Dorking - Littlehampton via Arundel
-
660V DC
Havant - West Worthing via Ford
-
660V DC
Barnham - Bognor Regis
-
660V DC
Motspur Park - Tolworth
-
660V DC
Virginia Water - Reading via Ascot
-
660V DC
Ascot - Ash Vale & connections
-
660V DC
Guildford - Aldershot
-
660V DC
-
660V DC
Pirbright Jct - Ash Vale Tolworth - Chessington South
-
660V DC
Gravesend - Strood - Maidstone West
-
660V DC
Strood - Gillingham via Rochester
-
660V DC
Swanley - Rochester via Longfield
-
660V DC
-
650V DC
Otford - Maidstone East via Kemsing Birkenhead Park - New Brighton & West Kirkby
-
600V DC
Newcastle Central - South Shields
-
600V DC
Gravesend Central - Gillingham, Strood & Maidstone West
-
600V DC
Swanley - Rochester
-
600V DC
Otford - Maidstone
550 V DC
630V DC
LUL Central Line
-
630V DC
Ealing Broadway - Wood Lane - Shepherds Bush - Bank Liverpool Street Liverpool Street - Stratford
-
630V DC
Stratford - Leytonstone
LUL Central Line
-
630V DC
North Acton - Greenford
LUL Central Line
-
630V DC
Leytonstone - Woodford
LUL Central Line
-
630V DC
Leytonstone - Newbury Park
LUL Central Line
-
630V DC
Newbury Park - Hainault
LUL Central Line
-
630V DC
Greenford - West Ruislip
LUL Central Line
-
630V DC
Woodford - Hainault
LUL Central Line
-
630V DC
Woodford - Loughton
LUL Central Line
-
630V DC
Loughton - Epping
LUL Central Line
-
1.5kV DC
London Liverpool Street - Shenfield
GE
-
1.5kV DC
London Fenchurch St - Bow Jct via Gas Factory Jct
LTS
Dunford Bridge - Wath
Woodhead Route
-
1.5kV DC
6.7kV 50Hz AC
25kV 50Hz AC
9
9
Manchester London Rd - Sheffield Victoria via Wath
Woodhead Route
-
1.5kV DC
Darnall Depot - Rotherwood Sidings
Woodhead Route
-
1.5kV DC
Shenfield - Chelmsford
GE
-
1.5kV DC
Shenfield – Southend Victoria
525V DC
-
All LOR Lines
500V DC
-
All G&IR Lines
Grimsby & Immingham Railway
-
630V DC
Epping - Ongar
LUL Central Line
-
25kV 50Hz AC
Wilmslow - Slade Lane
WCML test scheme
-
25kV 50Hz AC
Colchester - Clacton & Walton
25kV test scheme
-
750V DC
Gillingham - Ramsgate-Dover
6.25kV 50Hz AC London Liverpool St - Southend Victoria 6.25kV 50Hz AC Bethnal Green - Chingford, Enfield Town & Cheshunt
GE
6.25kV 50Hz AC Helensburgh - Glasgow Queen Street - Airdrie; Dalreoch - Balloch; Dalmuir Park - Hyndland via Westerton; Bellgrove - Springburn; Dalmuir Park - Yoker - Parkhead; High Street - Bridgeton 6.25kV 50Hz AC London Fenchurch St - Bow Jct via Gas Factory Jct
Glasgow suburban lines stage 1A
1961
Conversion
1961
9
1.5kV DC
New Build
1961
9
New Build
1961
New Build
1962
New Build
1962
New Build
1962
Conversion
1962
New Build
1963
New Build
1963
New Build
1963
New Build
1964
New Build
1964
Closure
1964
Closure
1964
New Build
1965
New Build
1965
New Build
1965
New Build
1966
New Build
1966
New Build
1966
New Build
1966
New Build
1966
New Build
1966
New Build
1966
De-electrification
1966
New Build
1967
New Build
1967
UK Equipment Information.xls
-
-
9 9
9 9
9 9
9 9 9 9 9 9 9 9 9 9 9 9 9
9
9
Liverpool Overhead Railway
1.5kV DC
-
9 9 9 9 9 9 9 9
Marsh Lane - Aintree
1.5kV DC
9 9 9
9 9
Lancaster - Morecambe - Heysham
-
630V DC
9 9
LUL Central Line
1.5kV DC
-
9 9
Wirral Extension
-
1.5kV DC
9
Route Designation
630V DC
-
9
Route
-
GE
LTS
Rickmansworth - Amersham/Chesham
LUL Metropolitan Line
25kV 50Hz AC
Crewe – Manchester
WCML stage 1
25kV 50Hz AC
Cheshunt - Bishops Stortford & Hertford East
6.25kV 50Hz AC Glasgow Central - Motherwell via Uddingston; Cathcart Circle; Cathcart - Neilston High 6.25kV 50Hz AC Gas Factory Jn - Shoeburyness; Barking - Pitsea via Grays; Barking Forest Gate Jn; Upminster - Grays 25kV 50Hz AC London Fenchurch St – Southend (via Laindon & Tilbury) 750V DC
-
750V DC
-
25kV 50Hz AC
Glasgow suburban lines stage 1B LTS LTS
Sevenoaks – Dover Kent Coast
Kent Coast
Southend - Shoeburyness
LTS WCML stage 2
-
25kV 50Hz AC
Crewe – Liverpool
1.5kV DC
25kV 50Hz AC
Shenfield - Chelmsford
-
25kV 50Hz AC
Stafford - Crewe
WCML stage 3
-
25kV 50Hz AC
Lichfield - Stafford
WCML stage 3
-
25kV 50Hz AC
Chelmsford - Colchester
-
25kV 50Hz AC
Nuneaton - Lichfield
WCML stage 3
-
25kV 50Hz AC
Rugby - Nuneaton
WCML stage 3
630V DC
-
Southport - Crossens
630V DC
-
Southport - Crossens via Meols Cop
-
1.5kV DC
-
25kV 50Hz AC
Cheadle Hulme - Macclesfield
WCML stage 4
-
25kV 50Hz AC
London Euston - Rugby inc Northampton Loop
WCML stage 5
-
25kV 50Hz AC
Wolverhampton - Stafford & Bescot; Portobello Jct - Bushbury Jct
WCML stage 6
-
25kV 50Hz AC
Camden - Camden Town
WCML stage 7
-
25kV 50Hz AC
Colwich - Macclesfield via Stone
WCML stage 8
-
25kV 50Hz AC
Stone - Norton Bridge
WCML stage 8
-
25kV 50Hz AC
Rugby - Wolverhampton via Birmingham
WCML stage 8
-
25kV 50Hz AC
Birmingham - Walsall
WCML stage 8
Aston - Stechford
WCML stage 8
Woodborn Jct & Darnall West Jct - Tinsley Yard
-
25kV 50Hz AC
6.7kV 50Hz AC
-
Lancaster - Morecambe - Heysham
-
25kV 50Hz AC
Glasgow - Gourock & Wemyss Bay
-
750V DC
Woking/Brookwood – Bournemouth
Woodhead Route
Glasgow suburban lines stage 2
13/08/2008
Railway Electrification Engineering Introduction to Overhead Line Electrification
New Build
1969
New Build
1969
New Build
1971
Conversion
1968
1971
New Build
1973
New Build
1973
New Build
1974
New Build
1974
New Build
1974
New Build
1975
New Build
1975
New Build New Build
1976 1976
New Build
1977 1977
New Build 1977
1978
New Build
1977
1978
Conversion
1979
Conversion
1979
Conversion
1979
New Build
1979
New Build
1979
New Build
1979
New Build
1979
New Build
1980
Closure
1981
New Build
1981
New Build
1981
New Build
1983
New Build
1983
Conversion
1983
Conversion
1983
Conversion
1983
Conversion
1984
New Build
1985
New Build
1985
New Build
1985
New Build
1985
New Build
1985
New Build
1985
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1986
New Build
1987 1987
New Build
1987
New Build
1987
New Build
1987
New Build
1987
New Build
1987
New Build
1987
New Build
1987
New Build
1988 1988 1988
New Build
1989
New Build
1989
New Build
1989
New Build
1989
New Build
1990
New Build
1990
New Build
1990
New Build
1991
New Build New Build
1991 1991
1990
UK Equipment Information.xls
Side
Bottom
Clapton Jct - Cheshunt Jct
Lea Valley
?
Warren Street - Victoria
LUL Victoria Line
-
?
Victoria - Brixton
LUL Victoria Line
1.5kV DC
25kV 50Hz AC
Manchester Oxford Rd - Altrincham
MSJ&A Line
-
25kV 50Hz AC
Weaver Jn - Bamfurlong (Freight Only)
WCML Extension stage 1
-
25kV 50Hz AC
Bamfurlong - Preston (Freight Only)
WCML Extension stage 2
-
25kV 50Hz AC
Weaver Jn - Preston (Passenger)
WCML Extension stage 3
-
25kV 50Hz AC
Preston - Glasgow Central
WCML Extension stage 4
-
25kV 50Hz AC
Lanark Jct - Lanark
9
9
9
9
9 9 9 9
9 9
9
9 9
9 9 9 9
9 9 9
9 9 9
9
1992
9
9
9
9 9 9 9 9 9
-
?
-
25kV 50Hz AC
-
25kV 50Hz AC 750V DC
9
9
9 9 9 9 9 9
9
9
9 9 9 9 9 9
9 9
9 9
9 9 9 9 9
9 9
9
9 9
9 9 9 9 9
9
9
9
9 9
9
9
9 9 9 9 9 9 9 9 9
9
9
9 9 9 9 9 9 9 9 9 9 9 9 9
9
9
Route
Hounslow West - Hatton Cross
Route Designation
LUL Piccadilly Line
Glasgow West St - Muirhouse Jct Drayton Park - Welwyn Garden City & Hertford North
Great Northern Suburban Stage 1
Moorgate-Drayton Park
Great Northern Suburban Stage 1
Hatton Cross - Heathrow Central
LUL Piccadilly Line
-
?
-
25kV 50Hz AC
Witham - Braintree
-
630V DC
Walton Jn - Kirkby
-
750V DC
Liverpool Central - Garston
-
750V DC
Fazakerley - Kirkby Dalmuir Park - Finnieston via Westerton; Yoker - Jordanhill; Westerton -Glasgow Suburban Milngavie London Kings Cross - Finsbury Park Great Northern Suburban Stage 2
-
25kV 50Hz AC
Welwyn Garden City - Royston
Great Northern Suburban Stage 2
6.25kV 50Hz AC
25kV 50Hz AC
Dalmuir Park - Yoker
Glasgow Suburban
6.25kV 50Hz AC
25kV 50Hz AC
Finnieston - Parkhead inc Bridgeton branch
Glasgow Suburban
6.25kV 50Hz AC
25kV 50Hz AC
Bellgrove - Springburn
Glasgow Suburban
6.25kV 50Hz AC
25kV 50Hz AC
Pollokshields East - Cathcart
Glasgow Suburban
-
25kV 50Hz AC
Hertford North - Stevenage
Great Northern Suburban Stage 2
Stanmore - Baker Street - Charing Cross
LUL Jubilee Line
-
?
-
25kV 50Hz AC
Cornbrook Jct - Trafford Park FLT
-
25kV 50Hz AC
Finnieston Jct - Rutherglen
-
1.5kV DC
-
-
-
25kV 50Hz AC 25kV 50Hz AC
9
1987
New Build
1990
25kV 50Hz AC
-
25kV 50Hz AC
Conversion
New Build
-
-
1979
1987
LUL Victoria Line
9 9 9 9 9 9 9
Conversion
New Build
9 9
LUL Victoria Line
Highbury - Warren Street
25kV 50Hz AC
1978
1987
9 9
Walthamstow Central - Highbury
?
6.25kV 50Hz AC
1978
New Build
9 9
?
-
9
New Build
1984
9 9
-
9
To
1978
New Build
New Build
9
9 9 9 9 9 9
1977
New Build
9
From
9
1977
New Build
9
Voltage
Side
1968
Centre
1968
New Build
4th
New Build
Electric Traction Equipment Type Contact Position Top
Finish
3rd
Start
OLE
Date Type
-
750V DC
Haymarket - St James, Bank Foot, Heworth & South Shields
Tyne & Wear Metro
Hadfield - Sheffield Victoria
Woodhead Route
Edgeley - Hazel Grove Mossend - Coatbridge FLT Garston - Hunts Cross
-
25kV 50Hz AC
London St Pancras & Moorgate – Bedford
6.25kV 50Hz AC
25kV 50Hz AC
London Liverpool St - Cheshunt
6.25kV 50Hz AC
25kV 50Hz AC
Hackney - Chingford
6.25kV 50Hz AC
25kV 50Hz AC
Bury Street - Enfield Town
1.5kV DC
25kV 50Hz AC
Manchester - Hadfield
-
750V DC
-
25kV 50Hz AC
Bishop's Stortford - Cambridge
-
25kV 50Hz AC
Freight Terminal Jct - Camden Road East Jct
-
25kV 50Hz AC
Navarino Road Jct - Reading Lane Jct
-
25kV 50Hz AC
Midland Mainline
Woodhead Route (truncated)
Rock Ferry - Hooton
Colchester - Ipswich
630V DC
Dalston - North Woolwich
-
660V DC
Blackfriars - Faringdon
Thameslink
-
25kV 50Hz AC
Paisley - Ayr
Ayrshire Coast
-
25kV 50Hz AC
Kilwinning - Ardrossan South Beach; Dubbs Jct - Byrehill Jct
Ayrshire Coast
-
25kV 50Hz AC
Hitchin - Huntingdon
ECML stage 1
Heathrow Airport
LUL Piccadilly Line
-
?
-
750V DC
-
25kV 50Hz AC
Manningtree - Harwich
-
25kV 50Hz AC
Ipswich - Stowmarket
-
25kV 50Hz AC
Romford - Upminster
-
25kV 50Hz AC
Wickford - Southminster
-
?
-
25kV 50Hz AC
-
750V DC
-
North London Line
Tonbridge - Hastings
Terminal 4 Loop Ardrossan South Beach - Largs & Ardrossan Harbour
Ayrshire Coast
Tower Gateway - Stratford & Island Gardens
Docklands Light Railway
25kV 50Hz AC
Huntingdon - Peterborough
ECML stage 2
-
25kV 50Hz AC
Stratford - Camden via Dalston
North London Line
-
25kV 50Hz AC
Stowmarket - Norwich
-
25kV 50Hz AC
Bishop's Stortford - Cambridge
-
25kV 50Hz AC
Glasgow – Ardrossan & Largs
-
25kV 50Hz AC
Canonbury Jct - Finsbury Park
-
25kV 50Hz AC
Stratford FLT
-
25kV 50Hz AC
Temple Mills Yard
-
750V DC
-
25kV 50Hz AC
Royston - Shepreth Branch Jct
-
25kV 50Hz AC
Watford Junction - St Albans Abbey
-
25kV 50Hz AC
Peterborough - Leeds via Doncaster
ECML stage 3
-
25kV 50Hz AC
Doncaster - York
ECML stage 4
-
25kV 50Hz AC
Seven Sisters - Tottenham South
-
25kV 50Hz AC
Airdrie - Drumgelloch
-
25kV 50Hz AC
York - Newcastle
-
25kV 50Hz AC
Stratford - Copper Mill Junction
-
25kV 50Hz AC
Stansted Jct - Stansted Airport
-
750V DC
-
25kV 50Hz AC
Carstairs – Edinburgh
-
25kV 50Hz AC
Drem Jct - North Berwick
-
25kV 50Hz AC
Lichfield - Birmingham New St; Aston - Redditch
Bournemouth - Weymouth
Royal Mint Street Jct - Bank
ECML stage 5
Docklands Light Railway
Cross City Line
13/08/2008
Railway Electrification Engineering Introduction to Overhead Line Electrification
New Build
1990
1992
New Build
1993
New Build
1993
New Build
1993
New Build
1992
New Build
1992
9
9
1993
New Build
1994
9 9
New Build
2000
New Build
2004
New Build
1999
New Build
1994
Closure New Build
1994
1996 1996
1996
1998
New Build
1999
Closure
1999
New Build
1999
New Build
2000
New Build New Build
2001 2001
New Build
2003 2003
New Build
2002
New Build
2003
New Build
2003
New Build New Build
Side
Centre
9
2005 2007 2010
2008
2010
New Build
2015
New Build
2015
New Build
2015
UK Equipment Information.xls
To
Route
Route Designation
25kV 50Hz AC
750V DC
Manchester - Altrincham
MJS&A; now Metrolink
1.2kV DC
750V DC
Manchester - Bury
Metrolink
-
25kV 50Hz AC
-
750V DC
-
25kV 50Hz AC
North Pole Depot
-
25kV 50Hz AC
Dollands Moor Freight Terminal
Channel Tunnel
-
25kV 50Hz AC
North Pole Jct - West London Jct
West London Line
Kensington Olympia? - North Pole Jct
West London Line
-
750V DC
-
25kV 50Hz AC 750V DC
Cambridge – King’s Lynn Hooton - Chester & Ellesmere Port Channel Tunnel
Manchester Airport North Spur
9
Sheffield - Meadowhall, Halfway, Herdings Park, Malin Bridge & Sheffield Supertram Middlewood Croydon - New Addington, Wimbledon, Beckenham Jct & Elmers End Croydon Tramlink
9 9 9
750V DC
Nottingham - Phoenix Park & Hucknall
750V DC
Birmingham Snow Hill - Wolverhampton
Midland Metro
Cheriton - Frethun
Channel Tunnel
Poplar - Beckton
Docklands Light Railway
-
9
9
9
9
1994
New Build Conversion
1994
9
Voltage From
750V DC
1994 1992
9
1993 1993
New Build
9
9 9
New Build
New Build
Side
9 9 9
Bottom
1992
4th
1992
Conversion
Top
Conversion
Start
3rd
Electric Traction Equipment Type Contact Position
Finish
OLE
Date Type
9 9 9 9
9 9
9 9 9 9 9 9 9 9 9 9 9 9
9
9
25kV 50Hz AC
-
750V DC
-
25kV 50Hz AC
-
-
-
Nottingham Express Transit
Leeds - Bradford, Skipton & Ilkley
Leeds North West
Holborn - Aldwych
LUL Piccadilly Line
25kV 50Hz AC
London Paddington - Heathrow Airport
Heathrow Express
25kV 50Hz AC
Manchester Airport South Spur
750V DC
25kV 50Hz AC
Acton Central - Camden Rd
North London Line
9
-
750V DC
Island Gardens - Lewisham
Docklands Light Railway
-
-
Green Park - Charing Cross
LUL Jubilee Line
9
-
?
Green Park - Stratford
LUL Jubilee Line Extension
-
25kV 50Hz AC
Kensal Green Jct - Willesden Jct
-
25kV 50Hz AC
Melton Jct - Edwalton
-
±25kV 50Hz AC Fawkenham Jct - Cheriton
Channel Tunnel Rail Link Section 1
-
25kV 50Hz AC
Crewe - Kidsgrove
WCRM
Pelaw Jct - Sunderland
Tyne & Wear Metro
Old Dalby Test Track
-
1.5kV DC
-
25kV 50Hz AC
-
±25kV 50Hz AC Fawkenham Jct - St Pancras International
Channel Tunnel Rail Link Section 2
-
25kV 50Hz AC
Shields Jct - Glasgow Airport
Glasgow Airport Scheme (GARL)
-
25kV 50Hz AC
Airdrie - Haymarket
Airdrie to Bathgate Scheme (A2B)
-
25kV 50Hz AC
Maidenhead - Stockley
Crossrail
-
25kV 50Hz AC
Royal Oak - Liverpool St
Crossrail
-
25kV 50Hz AC
Pudding Mill Lane - Abbey Wood
Crossrail
Haughhead Junction - Larkhall
13/08/2008
