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Third rail at the West Falls Church Metro stop in Washington, D.C., electrified to 750 volts. The third rail is at the top of the image, covered by the white canopy above it. The two lower rails are the ordinary running rails; current from the third rail eventually returns to the power station through these.

A British Class 442 electric multiple unit powered by a third rail in Dorset.

Hamburg. U-Bahn (or Hochbahn) line U3 near Hoheluftbrücke Station, an early example of the use of bottom-contact third rail.

Paris Metro. The guiding rails of the rubber-tyred lines are also current conductors. The current collector is between the pair of rubber wheels.

"London Stansted people mover" central rail.

"London Stansted people mover", shows rail switch.

A third rail is a method of providing electricity to power a railway by means of a continuous rigid conductor mounted alongside the railway track or between the rails. It is used typically in a mass transit or rapid transit system, which has alignments in own corridors, fully or almost fully segregated from the outside environment. A list of lines or networks equipped with third rail is towards the end of this entry. Third rail systems generally supply direct current to power the trains. Image File history File links Broom_icon. ... Image File history File links Download high resolution version (2304x1728, 1345 KB)Third rail for the Metro in Washington,DC, electrified to 750 volts. ... Image File history File links Download high resolution version (2304x1728, 1345 KB)Third rail for the Metro in Washington,DC, electrified to 750 volts. ... West Falls Church-VT/UVA is a Washington Metro station whose street address is 7840 Haycock Road in Fairfax County, Virginia on the Orange Line. ... Nickname: Motto: Justitia Omnibus (Justice for All) Location of Washington, D.C., in relation to the states Maryland and Virginia Coordinates: , Country United States Federal District District of Columbia Government  - Mayor Adrian M. Fenty (D)  - City Council Chairperson: Vincent C. Gray (D) Ward 1: Jim Graham (D) Ward 2: Jack... Download high resolution version (2048x1536, 625 KB)BR Class 442, no. ... Download high resolution version (2048x1536, 625 KB)BR Class 442, no. ... Image File history File linksMetadata Download high-resolution version (1488x1984, 614 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Third rail Metadata This file contains additional information, probably added from the digital camera or scanner used to... Image File history File linksMetadata Download high-resolution version (1488x1984, 614 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Third rail Metadata This file contains additional information, probably added from the digital camera or scanner used to... Image File history File links Download high resolution version (2048x1536, 351 KB) Beschreibung en: Description: A rubber-tired metro at Paris Author: Oldie Date: August 2003 License: GFDL History (Image:111-1195 IMG.JPG): 21:13, 23. ... Image File history File links Download high resolution version (2048x1536, 351 KB) Beschreibung en: Description: A rubber-tired metro at Paris Author: Oldie Date: August 2003 License: GFDL History (Image:111-1195 IMG.JPG): 21:13, 23. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2592 × 1944 pixel, file size: 1. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2592 × 1944 pixel, file size: 1. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2592 × 1944 pixel, file size: 1. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2592 × 1944 pixel, file size: 1. ... Third Rail was the first single released from Squeezes tenth album, Some Fantastic Place. ... Third rail consisting of two strips of aluminium fitted to a steel rail. ... Sunlight reflects off dual-gauge tracks near Chur, Switzerland Mixed-gauge track and pointwork (4 ft 8½ in (1435 mm) and 3 ft 6 in (1067 mm)) at Odawara in Japan Dual-gauge tram tracks in Katwijk, The Netherlands Dual-gauge or mixed-gauge railway is a special configuration of... Lightning strikes during a night-time thunderstorm. ... In the United States of America, transit describes local area common carrier passenger transportation configured to provide scheduled service on fixed routes on a non-reservation basis. ... A rapid transit, underground, subway, tube, elevated, or metro(politan) system is a railway—usually in an urban area—with a high capacity and frequency of service, and grade separation from other traffic. ... Direct current (DC or continuous current) is the continuous flow of electricity through a conductor such as a wire from high to low potential. ...

The third rail system of electrification is unrelated to the third rail used in dual-gauge railways. Sunlight reflects off dual-gauge tracks near Chur, Switzerland Mixed-gauge track and pointwork (4 ft 8½ in (1435 mm) and 3 ft 6 in (1067 mm)) at Odawara in Japan Dual-gauge tram tracks in Katwijk, The Netherlands Dual-gauge or mixed-gauge railway is a special configuration of...

History

Third-rail electric systems are, apart from on-board batteries, the oldest means of supplying electric power to trains on railways using own corridors, particularly in cities. Overhead power supply was initially almost exclusively used on tramway-like railways, though it also appeared slowly on mainline systems. (This statement describes the general trend; early particular cases may have been different.) A Pair of AA Energizer Alkaline Cells Symbols representing a single Cell (top) and Battery (bottom), used in circuit diagrams. ... It has been suggested that Local trains be merged into this article or section. ...

An experimental electric train using this method of power supply was developed by the German firm of Siemens & Halske and shown at the Berlin Industrial Exhibition of 1879. This pioneer electric railway had its third rail placed between running rails. At some early electric railways, though, one of the running rails could be the current conductor, as was the case of the 1883-opened Volk's Electric Railway in Brighton. Soon it was given an additional power rail in 1886 (the railway is still operating). The Giant's Causeway Tramway followed, equipped with an elevated outside third rail in 1883 (but later converted to overhead wire pickup). The first railway to use the central third rail was the Bessbrook & Newry Tramway, opened in Ireland in 1885 but now, like the Giant's Causeway line, closed. Also in the 1880s third-rail systems began to be used in public urban transport. Trams were first to benefit from it, but they used conductors built in conduit below the road surface (cf. Conduit current collection), and usually on selected parts of the networks. This was first tried in Cleveland (1884) and in Denver (1885) and later spread to many big tram networks (e.g. Manhattan, Chicago, Washington DC, London, Paris - all closed). Siemens AG (ISIN: DE0007236101, FWB: SIE, NYSE: SI) is one of the worlds largest companies and Europes largest engineering firm. ... 1879 (MDCCCLXXIX) was a common year starting on Wednesday (see link for calendar). ... 1883 (MDCCCLXXXIII) was a common year starting on Monday (see link for calendar). ... Half-way station VER Carriages Detail of the tracks in front of the carriage shed showing the electrified third rail. ... Year 1886 (MDCCCLXXXVI) was a common year starting on Friday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Sunday of the 12-day slower Julian calendar). ... The Giants Causeway & Bushmills Railway operates a narrow gauge 3ft (900mm) line between Giants Causeway and the old Bushmills distillery in Northern Ireland. ... 1883 (MDCCCLXXXIII) was a common year starting on Monday (see link for calendar). ... 1885 (MDCCCLXXXV) is a common year starting on Thursday of the Gregorian calendar (or a common year starting on Saturday of the 12-day slower Julian calendar). ... // Development and commercial production of electric lighting Development and commercial production of gasoline-powered automobile by Karl Benz, Gottlieb Daimler and Maybach First commercial production and sales of phonographs and phonograph recordings. ... Skytrain Bangkok. ... Conduit current collection was a system of current collection used by electric trams where the power supply was located in a channel under the roadway, rather than located overhead. ... Year 1884 (MDCCCLXXXIV) was a leap year starting on Tuesday (link will display the full calendar) of the Gregorian calendar (or a leap year starting on Sunday of the 12-day-slower Julian calendar). ... 1885 (MDCCCLXXXV) is a common year starting on Thursday of the Gregorian calendar (or a common year starting on Saturday of the 12-day slower Julian calendar). ...

A third rail supplied power to the world's first electric underground railway, the City & South London Railway, which opened in 1890 (now part of the Northern Line of the London Underground). In 1893 the world's second third-rail powered city railway opened in Britain - the Liverpool Overhead Railway (closed 1956 and dismantled). The first US third-rail powered city railway in revenue use was the 1895-opened Metropolitan West Side Elevated, which soon became part of the Chicago 'L'. In 1901, Granville Woods, a prominent African-American inventor, was granted a U.S. Patent 687,098 , covering various proposed improvements to third rail systems. This has been cited to claim that he invented the third rail system of current distribution. However, by that time there had been numerous other patents for electrified third-rail systems, including Thomas Edison's U.S. Patent 263,132  of 1882, and third rails had been in successful use for over a decade, in installations including the rest of Chicago 'elevateds', as well as these in Brooklyn, New York (if not to mention the development outside the US). To what extent Woods' ideas were adopted is thus a matter of controversy.[1] The City & South London Railway (C&SLR), originally known as City of London & Southwark Subway, is considered to be the first real deep-level tube railway in the world. ... 1890 (MDCCCXC) was a common year starting on Wednesday (see link for calendar) of the Gregorian calendar (or a common year starting on Friday of the Julian calendar). ... For other uses, see Northern Line (disambiguation). ... The Liverpool Overhead Railway opened the February 4, 1893. ... The L[1], variously, if perhaps incorrectly, styled L, El, EL, or L, is the rapid transit system that serves Chicago, Illinois in the United States. ... 1901 (MCMI) was a common year starting on Tuesday (link will display calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ... // Granville T. Woods (April 23, 1856 - January 30, 1910), born in Columbus, Ohio, was an African-American inventor. ... Languages Predominantly American English Religions Protestantism (chiefly Baptist and Methodist); Roman Catholicism; Islam Related ethnic groups Sub-Saharan Africans and other African groups, some with Native American groups. ... For other uses, see Inventor (disambiguation). ... Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman who developed many devices which greatly influenced life around the world, including the phonograph and a long lasting light bulb. ... Year 1882 (MDCCCLXXXII) was a common year starting on Sunday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Tuesday of the 12-day slower Julian calendar). ... This article needs additional references or sources for verification. ...

In Paris, in 1900, third rail appeared in the mainline tunnel connecting the Gare d'Orsay to the rest of the CF Paris-Orléans network. Mainline third rail electrification was later expanded to some suburban services in the French capital. Year 1900 (MCM) was an exceptional common year starting on Monday (link will display the full calendar) of the Gregorian calendar, but a leap year starting on Saturday of the Julian calendar. ... Gare dOrsay site seen from The Louvre in March 2006. ...

Top contact third rail (cf. below) seems to be the oldest form of power collection. Railways pioneering in using other, less hazardous types of third rail, were the New York Central Railroad on the approach to its NYC's Grand Central Terminal (1907 - another case of a third-rail mainline electrification) and the Hochbahn in Hamburg (1912) - both had bottom contact rail. However, the Manchester-Bury Line of the Lancashire & Yorkshire Railway tried the side contact rail (1917). These technologies appeared in wider use only at the turn of the 1920s and in the 1930s at, e.g., large-profile lines of the Berlin U-Bahn, the Berlin S-Bahn and the Moscow Metro. The New York Central Railroad (AAR reporting mark NYC), known simply as the New York Central in its publicity, was a railroad operating in the North-Eastern United States. ... The main concourse Grand Central Terminal (GCT, often unofficially called Grand Central Station) is a terminal rail station at 15 Vanderbilt Avenue (42nd Street and Park Avenue) in Midtown Manhattan in New York City. ... Year 1907 (MCMVII) was a common year starting on Tuesday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Monday of the 13-day-slower Julian calendar). ... The Hamburg U-Bahn is operated by Hamburger Hochbahn AG and belongs to the Hamburger Verkehrsverbund (HVV). ... 1912 (MCMXII) was a leap year starting on Monday in the Gregorian calendar (or a leap year starting on Tuesday in the 13-day-slower Julian calendar). ... The Lancashire and Yorkshire Railway (L&YR) was one of the major British railway companies which existed before the 1923 Grouping; although in 1922 it had already entered into a working agreement with the London and North Western Railway. ... 1917 (MCMXVII) was a common year starting on Monday of the Gregorian calendar (see link for calendar) or a common year starting on Tuesday of the 13-day slower Julian calendar (see: 1917 Julian calendar). ... The Oberbaumbrücke on the U1. ... Berlins S-Bahn network The Berlin S-Bahn is a metro system operated by S-Bahn Berlin GmbH, a subsidiary of the Deutsche Bahn. ... A current official map of the Moscow Metro. ...

In 1956 world's first rubber-tyred railway line was opened. This was Line 11 of Paris Metro. Power rail evolved into a pair of guiding rails required to keep the bogie in proper position on the new type of track. This solution was modified on the 1971-opened Namboku Line of Sapporo Subway, where a centrally placed guiding/return rail was used plus one power rail placed laterally as usually on steel rail railways (cf. photo). Paris Art Nouveau Metro sign The Paris Métro is the metro (underground) system in Paris, France. ... Sapporo Subway(札幌市営地下鉄: Sapporo Shiei Chikatetsu) is the rapid transit system in Sapporo, Hokkaido, Japan. ...

The third rail technology at street tram lines has recently been revived in the new system of Bordeaux (2004). This is a completely new technology (cf. below). A Citadis tram at the City Hall stop in Bordeaux The Bordeaux tramway network consists of three lines serving the capital of the Aquitaine Region in southwestern France. ... shelby was here 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ...

Third rail, being the older of the two electric current supply methods, is by no means obsolete. There are, however, countries (particularly Japan, South Korea, India, Spain) more eager to adopt overhead wiring to their urban railways. But in the same time there were (and still are) many new third rail systems built elsewhere, including technologically advanced countries (i.e. Copenhagen Metro, Taipei Metro, Wuhan Metro). Bottom powered railways (it may be too specific to use the term 'third rail') are also usually these having rubber-tyred trains, no matter if it is a heavy metro (except two other lines of Sapporo Subway) or a small capacity people mover (PM). Practically the only type of railways where third rail is no longer used in new systems is regional and long distance rail, which require higher speeds and voltages. The logo of the Metro. ... The Taipei Rapid Transit System (Traditional Chinese: ; pinyin: Táiběi Dàzhòng Jiéyùn Xìtǒng, also known as the MRT, Metro Taipei, or by locals simply as the Traditional Chinese: ; pinyin: Táiběi Jiéyùn) is a series of underground and elevated metro... The Wuhan Metro is an elevated metro system in the city of Wuhan, China. ... Sapporo Subway(札幌市営地下鉄: Sapporo Shiei Chikatetsu) is the rapid transit system in Sapporo, Hokkaido, Japan. ... A people mover is a fully-automated light rail or tram system. ...

With surface contact third (and fourth) rail systems a heavy "shoe" which is suspended from a wooden beam attached to the bogies (wheel units) collects power by sliding over the top surface of the electric rails. This view shows a class 313 train which operates primarily on Silverlink and First Capital Connect routes to the north and west of London.

The London Underground uses a four-rail system where both conductor rails are live relative to the running rails (the rails used by the train's wheels) though the positive rail has twice the voltage of the negative rail. Arcs like this are quite normal and occur when the electric power collection "shoes" of a train that is motoring (ie: drawing power) reach the end of a section of electric power rail.

Third rail consisting of two strips of aluminium fitted to a steel rail.

Image File history File links Top_contact_pickup_shoe. ... Image File history File links Top_contact_pickup_shoe. ... Class 313/0, no. ... Silverlink Trains is a regional franchise in the British railway system with routes in suburban London and from London to Northampton. ... First Capital Connect is a train operating company in England that began its passenger operations on the National Rail network at 02:00 BST 1 April 2006. ... Image File history File links Arcing_pickup_shoe. ... Image File history File links Arcing_pickup_shoe. ... The London Underground is a transit system that serves much of Greater London and some neighbouring areas. ... Download high resolution version (1280x960, 268 KB)Third rail at the South Station stop on the Boston subways Red Line. ... Download high resolution version (1280x960, 268 KB)Third rail at the South Station stop on the Boston subways Red Line. ...

Technical aspects

The third rail is usually located outside of the two running rails, but occasionally runs between them. The electricity is transmitted to the train by means of a sliding "shoe" (pick-up or contact shoe) which is held in contact with the rail. On many systems an insulating cover is provided above the third rail to protect employees working near the track; sometimes the shoe is designed to contact the side (called side running) or bottom (called bottom running) of the third rail, allowing the protective cover to be mounted directly to its top surface. When the shoe slides on top, it is referred to as "top running". When the shoe slides on the bottom it is not affected by the build-up of snow or leaves.

As with overhead wires, the return current on a third-rail system usually flows through one or both running rails, and leakage to ground is not considered serious. Where trains run on rubber tires, as on parts of the Paris Métro, Mexico City Metro and Santiago Metro, as well as on all of the Montreal Métro, live guide bars must be provided to feed the current. The return is effected through the rails of the conventional track between these guide bars (see rubber-tired metro). Another design, with a third rail (current feed, outside the running rails) and fourth rail (current return, half way between the running rails), is used by a few steel-wheel systems, see fourth rail. The London Underground is the largest of these, see railway electrification in Great Britain. Line 5s crossing of the Seine on the Austerlitz viaduct. ... Red del Metro de Ciudad de México A distinctive orange train on surface track near Metro General Anaya on Line 2 The Mexico City Metro (formally: Sistema de Transporte Colectivo Metro or STC Metro) provides metro service to the central and northern area of the Mexican Federal District and... The Santiago Metro symbol located at Escuela Militar station Metro de Santiago is the metro system serving the capital city of Santiago, Chile. ... This article does not cite any references or sources. ... A rubber-tyred train of the Paris Métro. ... Overhead wire in Coventry, England Overhead wire and its suspension system in Bridgeport, Connecticut, USA A railway electrification system is a way of supplying electric power to electric locomotives and multiple units. ... The London Underground is a transit system that serves much of Greater London and some neighbouring areas. ... // Railway electrification in Great Britain describes the various electrification systems that are used, or have been used, for supplying traction current to the railways and tramways of Great Britain. ...

In line M1 of the Milan underground, the third rail is used as the return electrical line (with potential near the ground) and the live electrical connection is made with a sliding block on the side of the car contacting an electrical bar located next to the railway (between the railway and the opposite direction railway) approximately 1 m (3') above the rail level. In this manner there are four rails. In the northern part of the line the more common overhead lines system is used. The Milan Metro is the subway system of Milan, Italy. ... The overhead lines of a Swiss Federal Railways track. ...

The third rail is an alternative to electrified overhead lines that transmit power to trains by means of pantograph arms attached to the trains. Whereas overhead-wire systems can operate at 25 kV or more, using alternating current (AC), the smaller clearance around a live rail imposes a maximum of about 1200 V (Hamburg S-Bahn), and direct current (DC) is used. Trains on some lines or networks use both power supply modes (cf. below, "Compromise systems"). The overhead lines of a Swiss Federal Railways track. ... A pantograph is a device that collects electric current from overhead lines for electric trains or trams. ... 25 kV AC is one of the most common voltages used for railway electrification, usually at 50 Hz or 60 Hz depending on that countrys normal mains frequency. ... City lights viewed in a motion blurred exposure. ... The Hamburg S-Bahn is the suburban S-Bahn railway network serving the city of Hamburg. ... Direct current (DC or continuous current) is the continuous flow of electricity through a conductor such as a wire from high to low potential. ...

One method for reducing current losses (and thus increase the spacing of feeder/sub stations - a major cost in third rail electrification) is to construct the conductor rail of a hybrid aluminium/steel design (or composite conductor rail). The aluminium, which is a better conductor of electricity, combined with a running face of stainless steel, which gives better wear, aims to match the existing steel conductor rails.

There are currently several marketed ways of attaching the stainless steel to the aluminium. The oldest is a co-extruded method, where the stainless steel is extruded with the aluminium. This method has suffered, in isolated cases, from de-lamination (where the stainless steel separates from the aluminium); this is said to have been eliminated in the latest co-extruded rails. A second method is an aluminium core, upon which two stainless steel sections are fitted as a cap and linear welded along the centre line of the rail. Because aluminium has a higher coefficient of thermal expansion than steel, the aluminium and steel must be positively locked to provide a good current collection interface. A third method rivets aluminum bus strips to the web of the steel rail. The photo on the right depicts such a rail. During heat transfer, the energy that is stored in the intermolecular bonds between atoms changes. ...

Advantages of third rail

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Cost Image File history File links This is a lossless scalable vector image. ...

Third-rail systems are cheaper to install than overhead wire systems, less prone to weather damage (other than flooding and icing, which cause major problems), and better able to fit into areas of reduced vertical clearance, such as tunnels and bridges. In many countries they were perceived as key means of reducing construction costs of tunnels, hence their popularity at underground railways.

Visual appeal

Third-rail systems cause less visual intrusion: they do not need overhead lines, which some people perceive as unsightly. Singapore, for example, has banned overhead wires on lines outside tunnels. Urban street railways have been built, for example in Washington DC, London, and Brussels, that carry the conductor rail within a slotted box in the center of the track (conduit current collection), primarily to avoid unsightly overhead wires and poles. These resemble the cable slot for a street cable car as seen in San Francisco. Rather than a mechanical grip, an insulated electrical pickup extends into the slot. The overhead lines of a Swiss Federal Railways track. ... Flag Seal Nickname: DC, The District Motto: Justitia Omnibus (Justice for All) Location Location of Washington, D.C., with regard to the surrounding states of Maryland and Virginia. ... This article is about the capital of England and the United Kingdom. ... Nickname: Map showing the location of Brussels in Belgium Coordinates: Country Belgium Region Brussels-Capital Region Founded 979 Founded (Region) June 18, 1989 Government  - Mayor (Municipality) Freddy Thielemans Area  - Region 162 km²  (62. ... Conduit current collection was a system of current collection used by electric trams where the power supply was located in a channel under the roadway, rather than located overhead. ... Cable Car in San Francisco A San Francisco cable car Winding drums on the London and Blackwall cable-operated railway, 1840. ... This page is a candidate for speedy deletion. ...

Robustness

Third-rail systems are more robust than overhead line systems, as the conductor rail is able to take higher mechanical forces than the contact wire of an overhead line system. The shoegear on a train is designed to shear off if it hits the conductor rail too hard, but as a train has many sets of shoegear, it is able to continue its journey. By contrast a pantograph is more likely to get tangled up in the overhead wires and not be able to continue its journey.

Maintenance access

Due to its accessible nature, a third rail system allows easy maintenance.

Compatibility

Many railways use third rail and DC power, even where overhead lines would otherwise be practical, due to the high cost of retrofitting. Every expansion of such system must cope with the problem of compatibility. It usually leads for the choice of already existing technology.

Disadvantages of third rail

The examples and perspective in this article or section may not represent a worldwide view of the subject. Please improve this article or discuss the issue on the talk page.

Third-rail systems have a number of problems and disadvantages, including: Image File history File links Gnome-globe. ...

Safety

An unguarded electrified rail is a safety hazard, and some people have been killed by touching the rail or by stepping on it while attempting to cross the tracks. However, such incidents are usually the result of carelessness on the part of the victim. The principal hazard is probably associated with level crossings. While their number on third rail lines is normally reduced to none, they still occur at some systems, particularly on rural and suburban portions of the network. One notable example of a Metro line is the outer end of the present Brown Line of Chicago 'L', running on street level in a densely populated neighborhood. The conductor is discontinued in the level crossing area. Pedestrians may be discouraged from trespassing into railway area by means of perforated panels difficult to step on ('cattle-cum-trespass guards'). They are laid between rails alongside the road. The term level crossing (also called a railroad crossing, railway crossing, train crossing or grade crossing) is a crossing on one level (at-grade intersection) — without recourse to a bridge or tunnel — of a railway line by a road, path, or another railroad. ... The Brown Line (Ravenswood Service) of the Chicago Transit Authority Chicago L rapid transit system, is a 11. ... The L[1], variously, if perhaps incorrectly, styled L, El, EL, or L, is the rapid transit system that serves Chicago, Illinois in the United States. ...

There are urban legends that people have died while urinating on the third rail (the urine stream supposedly completes an electrical circuit that electrocutes the victim); a non-continuous stream has been proven by MythBusters to be unable to conduct electricity [2]. This myth may be partially perpetuated by a 1977 incident that occurred in Chicago where an intoxicated pedestrian suffered a fatal electrocution injury while trespassing to urinate on the grade-level CTA Brown Line right-of-way near Kedzie Avenue. However, the death occurred as a result of the passenger making physical contact with the third rail (not as a result of an electrical circuit being completed via his urine stream)[3]. Urban Legend is also the name of a 1998 movie. ... Urination, also called micturition, is the process of disposing urine from the urinary bladder through the urethra to the outside of the body. ... MythBusters is a U.S. popular science television program on the Discovery Channel starring special effects experts Adam Savage and Jamie Hyneman, who use their skills and expertise to test the validity of various rumors and urban legends in popular culture. ...

A photo of the third rails used on the BART system. Notice how the rail changes location relative to the train upon entering the station for safety reasons (see article for more info).

• A new tramway system in Bordeaux, France surmounts the safety problem by using a third rail divided into insulated segments only a few metres long. Each segment is live only while completely covered by a tram, so there is no risk of a person or animal coming into contact with a live rail (see Third-rail power for trams for more information). This system would not be suitable for higher speeds, and the cost of breaking the live rail into short sections is considerable. This system was developed mainly for aesthetic reasons, to avoid overhead wires in front of the town hall.

• Other safety precautions can be made to reduce the risk of the third rail. Many subway systems, such as the BART and the Washington Metro, use sturdy sheaths to cover its third rails and always place the rail on the further side of the track away from where passengers would normally be. If someone falls on the tracks, there is room to return safely to the platform (or crawl under the platform) without the danger of stepping on the third rail.

Limited capacity Image File history File linksMetadata Download high-resolution version (2272x1704, 1764 KB) A picture showing the third rails on either side of the track on the BART system. ... Image File history File linksMetadata Download high-resolution version (2272x1704, 1764 KB) A picture showing the third rails on either side of the track on the BART system. ... A westbound BART train with aerodynamic design A car in downtown San Francisco. ... This article or section does not cite any references or sources. ... Bordeaux (Bordèu in Gascon) is a France. ... This article is about light rail systems in general. ... A westbound BART train with aerodynamic design A car in downtown San Francisco. ... The Washington Metro, or simply Metro, is the rapid transit system of Washington, D.C., and neighboring suburban communities in Maryland and Virginia, both inside and outside the Capital Beltway. ...

A relatively low voltage is necessary in a third-rail system — otherwise, electricity would arc from the rail to the ground or the running rails — but the resulting higher current (sometimes upwards of 3,000 amperes) causes more proportional voltage drop per mile, meaning that electrical feeder sub-stations have to be set up at frequent intervals along the line (generally no more than 10 miles or 16 km apart), increasing operating costs. The low voltage also means that the system is prone to overload, which makes such systems unsuitable for freight or high-speed trains demanding high amounts of power. These limitations of third-rail systems have largely restricted their use to mass transit systems. Capacity is also limited by speed restrictions – 160 km/h (100 mph) is considered to be the maximum speed at which a contact shoe can reliably collect power^{[citation needed]}.

By comparison, overhead wires can provide 25kV or even 50kV, and can take roughly ten times the power^{[citation needed]}.

Infrastructure restrictions

Junctions and other pointwork make it necessary to leave gaps in the live rail at times, as do level crossings. This is not usually a problem, as most third-rail rolling stock has multiple current collection shoes along the length of the train, but under certain circumstances it is possible for a train to become "gapped" - stalled with none of its shoes in contact with the live rail. When this happens, it is usually necessary for the train to be shunted back onto a live section either by a rescue locomotive or another service train, although in some circumstances it is possible to use jumper cables to temporarily hook the train's current collectors to the nearest section of live rail. Especially given that gapping tends to happen at complex, important junctions, it can be a major source of disruption. On the Chicago Transit Authority system, the jumper cables are known as stingers; they are insulated poles with a wired contact that may be manually pressed against contact shoes to restart a gapped train. Other such problems are implementation-specific, usually have workarounds. Another infrastructure restriction of third rail is that the rail and its safety cover decreases the structure gauge and in turn the loading gauge, potentially blocking access to certain types of equipment. The term level crossing (also called a railroad crossing, railway crossing, train crossing or grade crossing) is a crossing on one level (at-grade intersection) — without recourse to a bridge or tunnel — of a railway line by a road, path, or another railroad. ... Chicago Transit Authority, also known as CTA, is the operator of mass transit within the City of Chicago, Illinois. ... The Structure gauge, also called the minimum clearance outline, is the minimum size of tunnels and bridges as well as the minimum size of the doors that allow a rail siding access into a warehouse. ... A loading gauge is the envelope or contoured shape within which all railway vehicles, engines, coaches, and trucks must fit. ...

Inefficient contact

Fallen leaves, snow and other debris on the conductor rail can reduce the efficiency of the contact between the conductor rail and the pickup shoes, leaving trains stalled because of the lack of power. However, the bottom-contact third rail, as used on the Metro-North Railroad (see Technical aspects above), and numerous other transit systems including the Docklands Light Railway in London and the Market-Frankford Line in Philadelphia, is highly resistant to this problem. The Metro-North Railroad (officially the Metro-North Commuter Railroad Company, and usually abbreviated as Metro-North) is a suburban commuter rail service between New York City to its northern suburbs in New York and Connecticut. ... London Transport Portal The Docklands Light Railway (DLR) is a light rail system serving the redeveloped Docklands area of east London, England. ... This article is about the capital of England and the United Kingdom. ... Market-Frankford Line Map ©SEPTA 2004 The Market-Frankford Line (MFL) (also called the Market-Frankford Subway-Elevated Line (MFSE), El or Blue Line) is a transit line in Philadelphia, Pennsylvania, run by SEPTA. It begins at 69th Street Terminal just west of the city line in Upper Darby and... Nickname: City of Brotherly Love, Philly, the Quaker City Motto: Philadelphia maneto (Let brotherly love continue) Location in Pennsylvania Coordinates: Country United States State Pennsylvania County Philadelphia Founded October 27, 1682 Incorporated October 25, 1701 Mayor John F. Street (D) Area    - City 369. ...

Older systems adopted top-contact third rail before they realised that there would be problems with leaves, etc., while newer systems have learned from this mistake and use side or bottom contact. However, some relatively new systems in North America, such as the TTC in Toronto, use top-covered top-contact third rails on above-ground portions of its subway system; rarely is the system delayed by electrical problems even after heavy snows. Rather, problems generally arise in other aspects of the system (frozen switches for example) long before snow interferes significantly with electrical pickup. Some systems are less susceptible to this problem due to having mostly underground trackage, or less severe weather. The Toronto Transit Commission (TTC) is a public transport authority that operates buses, streetcars, subways, and rapid transit lines in Toronto, Ontario, Canada. ...

Compromise systems

Several systems use third rail for part of the system, and other systems such as overhead catenary or diesel power for the remainder. These may exist because of the connection of separately-owned railways using the different systems, local ordinances, or other historical accidents. For its use in ring theory, see Catenary ring. ...

USA

In New York City, electric trains that must use third rail leaving Grand Central Terminal on the former New York Central Railroad (now Metro-North Railroad) switch to overhead lines at Pelham when they need to operate out onto the former New York, New Haven and Hartford Railroad (now Metro North's New Haven Line) line to Connecticut. The switch is made "on the fly" controlled from the engineer's position. New York, New York and NYC redirect here. ... The main concourse Grand Central Terminal (GCT, often unofficially called Grand Central Station) is a terminal rail station at 15 Vanderbilt Avenue (42nd Street and Park Avenue) in Midtown Manhattan in New York City. ... The New York Central Railroad (AAR reporting mark NYC), known simply as the New York Central in its publicity, was a railroad operating in the North-Eastern United States. ... The Metro-North Railroad (officially the Metro-North Commuter Railroad Company, and usually abbreviated as Metro-North) is a suburban commuter rail service between New York City to its northern suburbs in New York and Connecticut. ... The overhead lines of a Swiss Federal Railways track. ... The New York, New Haven and Hartford Railroad (AAR reporting mark NH) was a railroad that operated in the northeast United States. ... Metro North Railroads New Haven Line runs from New Haven, Connecticut to Grand Central Terminal in Manhattan on trackage of the former New York, New Haven, and Hartford Railroad owned by the State of Connecticut and the State of New York. ... It has been suggested that this article be split into multiple articles. ...

Also in New York City, due to a prohibition on diesel emissions in tunnels, Metro-North Amtrak use diesel locomotives that can also be electrically powered by third-rail. This locomotive, the P32AC-DM, can transition between the two modes while underway. The third-rail auxillary system is not as powerful as the diesel engine, so on open-air (non-tunnel) trackage run the engines typically run in diesel mode, even where third rail power is available. Metro-North (officially MTA Metro-North Railroad) is a suburban commuter railroad running service from New York City to the northern suburbs in New York State and Connecticut. ... Acela Express in West Windsor, NJ Amtrak Cascades service with tilting Talgo trainsets in Seattle, Washington Amtrak train in downtown Orlando, Florida For other uses, see Amtrak (disambiguation). ... P32AC-DM is one of the three models of GE Genesis passenger locomotives. ...

In Manhattan, New York City, and in Washington, D.C., local ordinances required electrified street railways to draw current from a third rail and return the current to a fourth rail, both installed in a continuous vault underneath the street and accessed by means of a collector that passed through a slot between the running rails. When streetcars on such systems entered territory where overhead lines were allowed, they stopped over a pit where a man detached the collector (plow) and the motorman placed a trolley pole on the overhead. Some sections of the former London tram system also used the conduit current collection system, also with some tramcars that could collect power from both overhead and under-road sources. Manhattan is a borough of New York City, New York, USA, coterminous with New York County. ... Nickname: Motto: Justitia Omnibus (Justice for All) Location of Washington, D.C., in relation to the states Maryland and Virginia Coordinates: , Country United States Federal District District of Columbia Government  - Mayor Adrian M. Fenty (D)  - City Council Chairperson: Vincent C. Gray (D) Ward 1: Jim Graham (D) Ward 2: Jack... A motorman is the person who operates an electrified trolley car, tram, light rail, or rapid transit train. ... Trolley poles are usually tapered cylindrical poles of wood or metal, used to transfer electricity from a live overhead wire to the control and propulsion equipment of a trolley car, tram or trolley bus. ... This article is about the capital of England and the United Kingdom. ... Conduit current collection was a system of current collection used by electric trams where the power supply was located in a channel under the roadway, rather than located overhead. ...

The Blue Line of Boston's MBTA uses third rail electrification from the start of the line downtown to Airport, where it switches to overhead catenary for the remainder of the line to Wonderland. Dual power supply method was also used on some US interurban railways that made use of newer third rail in suburban areas, and existing overhead streetcar (trolley) infrastructure to reach downtown, for example the Skokie Swift in Chicago. A Blue Line train at the recently rebuilt Logan Airport station. ... Nickname: Location in Massachusetts, USA Coordinates: , Country United States State Massachusetts County Suffolk County Settled 1630 Incorporated (city) 1822 Government  - Governor Deval Patrick (D) Area  - City  89. ... The Massachusetts Bay Transportation Authority (MBTA) is a body politic and corporate, and a political subdivision of the Commonwealth of Massachusetts [2] formed in 1964 to finance and operate most bus, subway, commuter rail and ferry systems in the greater Boston, Massachusetts, USA area. ... Wonderland is the northern terminus of the MBTAs Blue Line. ... An interurban, also called a radial railway in parts of Canada, is a streetcar line running between urban areas or from urban to rural areas. ... Skokie Swift is a Chicago Transit Authority (CTA) line running from the Howard Street terminal on the northern city limits of Chicago to Skokie station at Dempster Street in Skokie. ...

UK

See also: Railway electrification in Great Britain

Several types of British trains operate on both overhead and third rail systems, including class 313, 319, 325 and 373 Eurostar trains. // Railway electrification in Great Britain describes the various electrification systems that are used, or have been used, for supplying traction current to the railways and tramways of Great Britain. ... Class 313/0, no. ... Class 319/0, no. ... Similar in end-on appearance to a Class 365 or Class 465 Networker unit, the Class 325 was British Rails wonderful new unit in the early 1990s to take over parcels working on electrified lines. ... The British Rail Class 373 or TGV-TMST train is an electric multiple unit that operates the Eurostar service from London Waterloo to France and Belgium. ... A Eurostar on the CTRL going through the Medway Towns Eurostar is a train service connecting the UK with Paris (Gare du Nord), Lille and Brussels (Brussels South). ...

The Eurostar uses overhead electrical power (at 25 kV AC) in the Channel Tunnel and along the CTRL, with a pantograph height change required between the CTRL line and the Channel Tunnel (which is a unique height). (The trains are also required to cope with height changes for the French urban and TGV lines). In the south-east a transition is made on-the-fly to 750 V DC for the remainder of the journey through the London suburbs, on the standard commuter lines into Waterloo using the third rail system. From 2007, upon completion of the Channel Tunnel Rail Link, there will be overhead electricity all the way into London. A Eurostar on the CTRL going through the Medway Towns Eurostar is a train service connecting the UK with Paris (Gare du Nord), Lille and Brussels (Brussels South). ... Map of the Channel Tunnel. ... CTRL redirects here. ... Model showing the current redevelopment of the Kings Cross area with the Channel Tunnel Rail Link terminal behind the barrel vaulted St Pancras Station on the left. ... This article is about the capital of England and the United Kingdom. ... CTRL redirects here. ...

Also in London, the cross-city Thameslink service runs on Southern Region third rail from Farringdon station southwards and on overhead line northwards from Farringdon up to Bedford: this change-over is made while stationary. This Thameslink article does not cite its references or sources. ... Farringdon station platforms Farringdon station is a London Underground and National Rail station in Farringdon, just north of the City of London in the London Borough of Islington. ...

Continental Europe

The older lines in the west of the Oslo T-bane system were built with overhead lines (some since converted to third rail) while the eastern lines were built with third rail. Trains operating on the older lines can operate both with third rail and overhead lines. To mitigate investment costs, the Rotterdam Metro, basically a third-rail powered system, has been given some outlying branches built on surface as light rail (called 'Sneltram' in Dutch), with numerous level crossings protected with barriers and traffic lights. These branches have overhead wires. Similarly, in Amsterdam one 'Sneltram' route goes on Metro tracks and passes to surface alignment in the suburbs, which it shares with standard trams. In most recent developments, the RandstadRail project also requires Rotterdam Metro trains to run under wires on their way along the former mainline railway to The Hague. The T-bane is the metro system of Oslo, Norway, operated by Oslo T-banedrift, a subsidiary of the municipality transit authority Oslo Sporveier. ... Rotterdam Metro sign at Delfshaven station MG2/1-metro series 5300, builded by Bombardier MG2-train in station The Rotterdam Metro is a subway operated in Rotterdam by RET. The first line, called Noord - Zuidlijn (North - South line) openend February 8, 1968, and ran from the Centraal Station to Zuidplein... This article is about light rail systems in general. ... The lines of the Amsterdam metro Gemeentelijk Vervoerbedrijf (GVB) operates the Amsterdam Metro system, along with the Amsterdam Trams, Ferries and a number of Bus Lines. ... RandstadRail is a lightrail public transport system in the southern area of the Randstad conurbation in The Netherlands. ...

The newly built tramway in Bordeaux (France) uses a novel system with a third rail in the center of the track. The third rail is separated into 8 m (26 ' 3 ") long conducting and 3 m (9 ' 10 ") long isolation segments. Each conducting segment is attached to an electronic circuit which will make the segment live once it lies fully beneath the tram (activated by a coded signal sent by the train) and switch it off before it becomes exposed again. This system (called "Alimentation par Sol" (APS), meaning "current supply via ground") is used in various locations around the city but especially in the historic centre: elsewhere the trams use the conventional overhead lines, see also ground-level power supply. In summer 2006 it was announced that two new French tram systems would be using APS over part of their networks. These will be Angers and Reims, with both systems expected to open around 2009 / 2010. This article does not cite any references or sources. ... The overhead lines of a Swiss Federal Railways track. ... Bordeaux trams run without overhead wires. ... Maison dAdam, House of Adam, the oldest house of Angers. ... Reims (English traditionally Rheims) (pronounced in French) is a city of northern France, 144 km (89 miles) east-northeast of Paris. ... 2009 (MMIX) will be a common year starting on Thursday of the Gregorian calendar. ... This article does not cite any references or sources. ...

Conversions from and to third rail

Despite various technical possibilities of operating stock with dual power collecting modes, the desire to achieve full compatibility of entire networks seems to have been the decisive cause of conversions from third rail to overhead supply (or vice versa).

Selected suburban corridors in Paris, focusing at Gare Saint-Lazare, Gare des Invalides (both CF Ouest) and Gare d'Orsay (CF PO), were electrified from 1924, 1901, 1900 respectively. They all changed to overhead wires by stages after they became part of a wide scale electrification project of the SNCF network (the 1960s-70s). Gare Saint-Lazare is Paris busiest railway station. ... List of stations of the Paris Métro Invalides is a station of the Paris Métro and RER, located near and named after Les Invalides. ... Gare dOrsay site seen from The Louvre in March 2006. ... The Chemin de Fer de Paris à Orléans, often abbreviated to CF Paris-Orléans, was an early French railway company. ... An SNCF multiple unit. ...

In Manchester area, the aforementioned Bury Line (originally L&YR) was first electrified with overhead wires (1913), then changed to third rail (1917, cf. Railway electrification in Great Britain) and again in 1992 to overhead wires in the course of its adaptation for the Manchester Metrolink. Trams in city centre streets, carrying collector shoes projecting from their bogies, were considered too dangerous for pedestrians and motor traffic to attempt dual-mode technology (in Amsterdam and Rotterdam Sneltram vehicles go out to surface in suburbs, not in busy central areas). The same thing happened to the West Croydon - Wimbledon Line in Greater London (originally electrified by the Southern Railway) when Croydon Tramlink was built (opened 2000). The Lancashire and Yorkshire Railway (L&YR) was a major British railway company before the 1923 Grouping, although in 1922 it had already entered into a working agreement with the London and North Western Railway. ... // Railway electrification in Great Britain describes the various electrification systems that are used, or have been used, for supplying traction current to the railways and tramways of Great Britain. ... A Metrolink tram in Manchester city centre. ... The Southern Railway in the United Kingdom was the smallest of the four railway systems created in the Grouping ordered by the Railways Act 1921. ... a Tramlink Tram Tramlink (until recently known as Croydon Tramlink) is a public transport system in south London, operated by FirstGroup on behalf of Transport for London. ...

Three lines of five making up the core of Barcelona Metro network changed to overhead power supply from third rail. This operation was also done by stages and completed in 2003. Plaça de Catalunya station The Barcelona Metro, part of the mass transit public transport system of Barcelona, Catalonia, Spain is an extensive network of electrified railways that run underground in central Barcelona and above ground into the citys suburbs. ...

Quite the opposite thing took place in London. The South London Line of the LBSCR network (between Victoria and London Bridge Stations) was electrified with catenary in 1909 - the system was later extended to Crystal Palace, Coulsdon North and Sutton. In the course of mainline third rail electrification in south-east England, the lines were converted accordingly by 1929. The LB&SCRs coat of arms, displayed above the entrance to Gipsy Hill railway station. ...

The first overhead electric trains appeared on the de:Hamburg-Altonaer Stadt- und Vorortbahn in 1907. Thirty years later, the mainline railway operator, Deutsche Reichsbahn, influenced by the success of the third-rail Berlin S-Bahn, decided to switch what was now called Hamburg S-Bahn to third rail. The process began in 1940 and was not finished until 1955. The Deutsche Reichsbahn (German State Railways; abbreviated DR) was the national railway service of the German Democratic Republic (GDR). ... Berlins S-Bahn network The Berlin S-Bahn is a metro system operated by S-Bahn Berlin GmbH, a subsidiary of the Deutsche Bahn. ... The Hamburg S-Bahn is the suburban S-Bahn railway network serving the city of Hamburg. ...

In 1976-1981 the third-rail Viennese U-Bahn U4 Line substituted the Donaukanallinie and Wientallinie of the Stadtbahn, built c1900 and first electrified with overhead wires in 1924. This was part of a big project of consolidated U-Bahn network construction. The other electric Stadtbahn line, whose conversion into heavy rail stock was rejected, still operates under wires with light rail cars (as U6), though it has been thoroughly modernised and significantly extended. As the platforms on the Gürtellinie were not suitable for raising without much intervention into historic Otto Wagner's station architecture, the line would anyway remain incompatible with the rest of the U-Bahn network. Therefore an attempt of conversion to third rail would have been pointless. In Vienna, paradoxically, the wires were retained for aestetic (and economic) reasons. Vienna U-Bahn logo The Vienna U-Bahn is a rapid transit (Metro) system consisting of five lines mostly running underground, except for the central section of line U6, which runs above ground on the viaduct of the old Vienna Stadtbahn. ... Opening of the Wiener Stadtbahn (postcard 1898) The Wiener Stadtbahn (German for Vienna City Railway) was a public transportation system that operated from 1898 to 1989. ... Otto Wagner Otto Koloman Wagner (13 July 1841–11 April 1918) was an Austrian architect. ...

The already discussed Skokie Swift of Chicago 'L' changed to third rail in 2004, to make it compatible with the rest of the system. The Yellow Line, formerly known as the Skokie Swift, is a Chicago Transit Authority (CTA) rapid transit line running from the Howard Street terminal on the northern city limits of Chicago to Skokie station at Dempster Street in Skokie. ... The L[1], variously, if perhaps incorrectly, styled L, El, EL, or L, is the rapid transit system that serves Chicago, Illinois in the United States. ...

The reasons for building the overhead powered Tyne & Wear Metro network roughly on lines of the long-gone third-rail Tyneside Electrics system in Newcastle area are likely to have roots in economy and psychology rather than in the pursue of compatibility. At the time of the Metro opening (1980) there were no third-rail light rail vehicles on the market and the latter technology was confined to much more costly heavy rail stock. Also the far-going change of image was desired: the memories of the last stage of operation of the Tyneside Electrics were far from being favourable. This was the construction of the system from scratch after eleven years of ineffective diesel service. The Tyne and Wear Metro is a light rail metro system in Tyne and Wear in north-east England, which opened in 1980, and in 2002-3 served 40 million journeys. ... The Tyneside Electric refers to the suburban railways on Tyneside that were electrified by the North Eastern Railway from 1904 onwards; they formed one of the earliest suburban electric networks. ...

List of Systems using third rail

See List of rail transport systems using third rail for a complete list. Third rail railways predominantly operate in urban contexts. ...

See also

Third rail railways predominantly operate in urban contexts. ... Conduit current collection was a system of current collection used by electric trams where the power supply was located in a channel under the roadway, rather than located overhead. ... Bordeaux trams run without overhead wires. ... A rubber-tyred train of the Paris Métro. ... This article is about light rail systems in general. ... This is an alphabetical list of cities worldwide that have a rapid transit system, or a light-rail system with some elements of rapid transit. ... This is an alphabetical listing of countries and cities that have commuter or suburban railways. ... // Railway electrification in Great Britain describes the various electrification systems that are used, or have been used, for supplying traction current to the railways and tramways of Great Britain. ... Overhead wire in Coventry, England Overhead wire and its suspension system in Bridgeport, Connecticut, USA A railway electrification system is a way of supplying electric power to electric locomotives and multiple units. ...

External links

Wikimedia Commons has media related to:

Third rail

• Thomas Edison's third rail patent (1882)
• Lightrail without wires - Paper on Bordeaux' new Tram with street level third rail (by the Transportation Research Board of the National Academies)

• Details of the UK 3rd/4th rail design.
• The "third rail" A short history.

Image File history File links Commons-logo. ... The Wikimedia Commons (also called Wikicommons) is a repository of free content images, sound and other multimedia files. ...