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A classic Belgian multiple unit of type 74

The term Multiple Unit or MU is used to describe a self propelling train unit capable of coupling with other like units and being controlled from one cab. The term is most often used on passenger trainsets that consists of more than one carriage, but single self propelling carriages, or railcars, can be referred to as multiple units if capable of operating with other units. Multiple-unit train control sometimes referred to simply as multiple-unit or MU, is a method of simultaneously controlling all the motors in a train including a number of self-powered cars from a single operating location. ... Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ... An interior view of a modern Finnish bilevel intercity coach. ... Not to be confused with Railroad car A railcar is a self-propelled rail vehicle designed to transport passengers. ...

Multiple units are of two main types:

• Electric Multiple Unit (EMU)
• Diesel Multiple Unit (DMU)

Trains of the Singapore MRT. EMUs are often used for rapid transit lines. ... DMU, type SA108 of Great Poland Voivodship in Poznań, Poland The Transwa Prospector DEMU capable of up to 200km/h provides a passenger service between Perth, Western Australia and the mining town of Kalgoorlie A Diesel Multiple Unit or DMU is a multiple unit train consisting of multiple carriages powered...

History and description

Multiple unit operation was made possible by the development of multiple-unit train control by the American inventor (Franklin J. Sprague). This allowed electrically-powered rapid transit trains to be operated from a single driving position. Multiple-unit train control sometimes referred to simply as multiple-unit or MU, is a method of simultaneously controlling all the motors in a train including a number of self-powered cars from a single operating location. ... For other uses, see Inventor (disambiguation). ... Frank Julian Sprague (1857-1934) American inventor, Father of Electric Traction Frank Julian Sprague (1857–1934) was an American naval officer and inventor who contributed to the development of the electric motor, electric railways, and electric elevators. ... Lightning strikes during a night-time thunderstorm. ... 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. ...

Most MUs are powered either by a diesel engine driving the wheels through a gearbox or hydraulic transmission (DMU), or by electric motors, receiving their power through a live rail or overhead wire (EMU). Diesel electric multiple units (DEMUs) have a diesel engine that drives a generator producing electricity to drive electric motors in a similar fashion to a Diesel-electric locomotive. This article does not cite any references or sources. ... DMU, type SA108 of Great Poland Voivodship in Poznań, Poland The Transwa Prospector DEMU capable of up to 200km/h provides a passenger service between Perth, Western Australia and the mining town of Kalgoorlie A Diesel Multiple Unit or DMU is a multiple unit train consisting of multiple carriages powered... Rotating magnetic field as a sum of magnetic vectors from 3 phase coils An electric motor converts electrical energy into mechanical energy. ... Third rail at Bostons South Station A third rail is a method of providing electricity to power a railroad, typically a mass transit system. ... The overhead lines of a Swiss Federal Railways track. ... Southern Class 205 unit no. ... A modern Diesel locomotive. ...

Trainset

Virtually all rapid transit rolling stock, such as ones used in subway systems, are multiple unit trainsets, usually EMUs. Many high-speed rail rolling stocks are also multiple unit trainsets, such as the Japanese Shinkansen and the German ICE 3 high-speed trains. 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. ... French designed Eurostar and Thalys TGVs side-by-side in the Paris-Gare du Nord. ... 300 (left) and 700 Series Shinkansen at Tokyo Station Shinkansen 500 Series at Kyoto Station, March 2005 The Shinkansen ) is a network of high-speed railway lines in Japan operated by Japan Railways. ... Siemens Velaro is a family of high-speed EMUs. ... French designed Eurostar and Thalys TGVs side-by-side in the Paris-Gare du Nord. ...

A multiple unit trainset has the same power and traction components as a locomotive, but instead of the components concentrating in one carbody, they are spread out on each car that makes up the set. Therefore these cars can only propel themselves when they are part of the complete trainset, thus making them semi-permanently coupled. For example, a DMU might have one car carry the prime mover and traction motors, and another the engine for head end power generation; an EMU might have one car carry the pantograph and transformer, and another car carry the traction motors. Great Western Railway No. ... For the philosophical/theological concept of a prime mover (that is, a self-existent being that is the ultimate cause or mover of all things), see cosmological argument. ... Traction motor typically refers to those motors that are used to power the driving wheels of a railroad locomotive, electrical multi-unit train (such as a subway or light rail vehicle train), or a tram. ... Head end power (also known as hotel power) is a method of providing electricity to the carriages of a train, usually the passenger carriages of a long distance hotel train. ... A pantograph is a device that collects electric current from overhead lines for electric trains or trams. ... Figure 1:Three-phase pole-mounted step-down transformer. ...

Multiple Units vs. Locomotives

Advantages

Polish class EN57 EMUs waiting for service in Poznań

Multiple units have several advantages over locomotive-hauled trains: Image File history File links Metadata Size of this preview: 713 × 599 pixelsFull resolution (772 × 649 pixel, file size: 241 KB, MIME type: image/jpeg) Photo: Radomil, 20 March 2005, Poznan File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old... Image File history File links Metadata Size of this preview: 713 × 599 pixelsFull resolution (772 × 649 pixel, file size: 241 KB, MIME type: image/jpeg) Photo: Radomil, 20 March 2005, Poznan File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old... EN57 is a name for Polish electric multiple unit while used in Polish railway operator (PKP). ... Poznań ( ; full official name: The Capital City of Poznań, Polish: Stołeczne Miasto Poznań (Latin: , German: , Yiddish: פּױזן Poyzn) is a city in west-central Poland with over 578,900 inhabitants (2002). ...

• Energy Efficiency - MUs are more energy efficient than locomotive-hauled trains. They are more nimble, especially on grades, as much more of the train's weight (sometimes all of it) is carried on power-driven wheels, rather than suffer the dead weight of unpowered hauled coaches;

• No need to turn locomotive - Most MUs have cabs at both ends, resulting in quicker turnaround times, reduced crewing costs, and enhanced safety. The faster turnaround time and the reduced size (due to higher frequencies) as compared to large locomotive-hauled trains, has made the MU a major part of suburban commuter rail services in many countries. MUs are also used by most rapid transit systems.

• Consist can be changed mid journey - MUs may usually be quickly made up or separated into sets of varying lengths. Several multiple units may run as a single train, then be broken at a junction point into smaller trains for different destinations.

• Reliability – Due to having multiple engines the failure of one engine does not prevent the train from continuing its journey. A locomotive drawn train typically only has one power unit whose failure will disable the train. Some locomotive hauled trains may contain more than one power unit and thus be able to continue at reduced speed after the failure of one.

The latest example of a Swiss EMU in Zürich HB

• Safety – Multiple units normally have completely independent braking systems on all cars meaning the failure of the brakes on one car does not prevent the brakes from operating on the other cars

• Axle load - Multiple units have lighter axle loads, allowing operation on lighter tracks, where locomotives are banned, such as the Whitby line in the UK. Another side effect of this is reduced track wear, as traction forces can be provided through many axles, rather than just four or six.

Great Western Railway No. ... A Connex commuter train stands by the platform in Melbourne, Australia Regional rail systems, or commuter rail systems, usually provide a rail service through a central business district area into suburbs or other locations that draw large numbers of people on a daily 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. ... Great Western Railway No. ... It has been suggested that Local trains be merged into this article or section. ... Image File history File links Size of this preview: 800 × 524 pixelsFull resolution (1490 × 976 pixel, file size: 205 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Size of this preview: 800 × 524 pixelsFull resolution (1490 × 976 pixel, file size: 205 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Wikipedia:Translation/Zürich HB railway station Zürich Main Station ticket hall Zürich Main Station -- tracks Zürich Main Station (in German: Zürich Hauptbahnhof, often shortened to Zürich HB) is Zürichs central and biggest railway station. ... Whitby is a historic town in North Yorkshire on the north-east coast of England. ...

Disadvantages

Multiple Units do have some disadvantages as compared to locomotive hauled trains:

• Maintenance - It may be easier to maintain one locomotive than many self-propelled cars.

• Safety - In the past it was often safer to locate the train's power systems away from passengers. This was particularly the case for steam locomotives, but still has some relevance for other power sources. A head on collision involving a multiple-unit (with passengers potentially right at the front of the train) is likely to result in more casualties than one with a locomotive (where the locomotive would act as a 'crumple zone').

• Easy replacement of motive power - Should a locomotive fail, it is easily replaced. Failure of a multiple unit train-set will often require a whole new train or time-consuming switching.

• Efficiency - Idle trains do not waste expensive motive power resources. Separate locomotives mean that the costly motive power assets can be moved around as needed.

• Flexibility - Large locomotives can be substituted for small locomotives where the gradients of the route become steeper and more power is needed.

• Noise - The passenger environment of a multiple unit is often noticeably noisier than in a locomotive-hauled train, due to the presence of underfloor machinery. This is a particular problem with DMUs.

• Obsolescence cycles - Separating the motive power from the payload-hauling cars means that either can be replaced when obsolete without affecting the other.

• It is difficult to have gangways between coupled sets, and retain an aerodynamic leading front end.

DMU, type SA108 of Great Poland Voivodship in Poznań, Poland The Transwa Prospector DEMU capable of up to 200km/h provides a passenger service between Perth, Western Australia and the mining town of Kalgoorlie A Diesel Multiple Unit or DMU is a multiple unit train consisting of multiple carriages powered...

Features

Two coupled ICE 3 on the Cologne-Frankfurt high-speed rail line near Montabaur

It is not necessary for every single car in a MU to be motorized. Therefore EMU cars can be motor units, or can be trailing units. Instead of motors, trailing units can contain some supplemental equipment such as air compressors, batteries, etc. Image File history File linksMetadata Size of this preview: 800 × 534 pixelsFull resolution (1000 × 667 pixel, file size: 324 KB, MIME type: image/jpeg) (All user names refer to de. ... Image File history File linksMetadata Size of this preview: 800 × 534 pixelsFull resolution (1000 × 667 pixel, file size: 324 KB, MIME type: image/jpeg) (All user names refer to de. ... ICE 3 trainset near Ingolstadt The InterCityExpress or ICE (German pronunciation: ) is a system of high-speed trains predominantly running in Germany and its neighbouring countries. ... Lahn bridge near Limburg The Cologne-Frankfurt high-speed rail line (in German: Neubaustrecke Köln-Rhein/Main) is a 177 km long railway line in Germany, connecting the cities of Cologne and Frankfurt. ... Town hall in Montabaur Montabaur is a town and a municipality in Rhineland-Palatinate, Germany, capital of the Westerwaldkreis district. ...

In some EMU trains, every car is equipped with a driving console, and other controls necessary to operate the train. Therefore every car can be used as a cab car whether it is motorised or not, if on the end of the train. This is the case with NJ Transit Arrows, Metro-North Railroad (New York) EMUs, etc. However, other EMUs can be driven/controlled only from dedicated Cab cars. Among such EMUs are Ex-USSR-made ER2, ER9, German classes 423-426, etc. New Jersey Transit Arrow III at West Windsor, NJ Hudson-Bergen Light Rail vehicle at 2nd Street station New Jersey Transit (NJ Transit) is a statewide public transportation system serving the U.S. state of New Jersey. ... The Metro-North Commuter Railroad Company, or MTA Metro-North Railroad, or, more commonly, Metro-North, is a suburban commuter rail service that is run and managed by an authority of New York State, the Metropolitan Transportation Authority, or, more simply, the MTA. Metro-North runs service between New York... For servicing suburban commuter lines, electrified on 25 kV, AC, the Railcar Manufacturing Plant of Riga produced ER9, then ER9p electric trainsets in the 1966-1975 period. ...

Well-known examples of MUs are the Japanese Shinkansen and the last generation German ICE. Most trains in the Netherlands and Japan are MUs, making them suitable for use in areas of high population density. Even some freight trains are MUs: the M250, whose four front and end carriages are EMUs, has been operating in Japan since March 2004. 300 (left) and 700 Series Shinkansen at Tokyo Station Shinkansen 500 Series at Kyoto Station, March 2005 The Shinkansen ) is a network of high-speed railway lines in Japan operated by Japan Railways. ... ICE 3 trainset near Ingolstadt The InterCityExpress or ICE (German pronunciation: ) is a system of high-speed trains predominantly running in Germany and its neighbouring countries. ...

EMUs are also extensively used in all local train networks in India that provide commuter transport in all the major cities.

Ireland

Main article: Multiple Units of Ireland

A wide variety of diesel and electric multiple units have been used on Ireland's railways. A wide variety of diesel and electric multiple units have been used on Irelands railways. ...

In Northern Ireland the majority of passenger services have been operated by diesel multiple units since the mid-1950s under the tenure of both the Ulster Transport Authority (1948-1966) and Northern Ireland Railways (since 1967). Northern Ireland (Irish: ) is a part of the United Kingdom lying in the northeast of the island of Ireland, covering 5,459 square miles (14,139 km², about a sixth of the islands total area). ... UTAs logo The Ulster Transport Authority (UTA) ran rail and bus transport in Northern Ireland from 1948 until 1966. ... 1906 reference Rail Map Northern Ireland Railways (NIR or NI Railways) – formerly, and very briefly, known as Ulster Transport Railways (UTR) – is the railway operator in Northern Ireland. ...

In the Republic of Ireland the railway operator Iarnród Éireann has purchased a number of new multiple units since 1987 to replace older locomotives and carriages. Current Iarnród Eireann (Irish Rail) intercity rail network An IÉ commuter train at Tara Street Station, Dublin, 2006 IÉ no. ...

North America

NJ Transit EMUs

Most long-distance trains in North America are locomotive-hauled. However, commuters, subway, and light rail operations make extensive use of MUs. Most electrically powered trains are MUs. The Southeastern Pennsylvania Transportation Authority (SEPTA) Regional Rail Division uses EMUs almost exclusively - the exception being some of its peak express service. New Jersey Transit service on the Northeast Corridor is split between electric locomotives and EMUs. Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (1024 × 768 pixel, file size: 233 KB, MIME type: image/jpeg)Arrow-III trains, which are used on NJ Transit, draw power by double hand pantographs. ... Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (1024 × 768 pixel, file size: 233 KB, MIME type: image/jpeg)Arrow-III trains, which are used on NJ Transit, draw power by double hand pantographs. ... 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. ... This article is about light rail systems in general. ... For the abbreviation SEPTA, see SEPTA. A septum, in general, is a wall separating two cavities or two spaces containing a less dense material. ... The New Jersey Transit Corporation (NJ Transit) is a statewide public transportation system serving the state of New Jersey, and Orange and Rockland counties in New York. ... Most of the NEC (those sections shown in red, except Boston to the Rhode Island state line) is owned by Amtrak. ...

M2, M4, M6 and future M8 EMUs which operate on the New Haven Line of Metro-North Railroad, are “dual mode” meaning they can draw power from either the third rail or from overhead lines. This allows operation under the wires between Pelham, NY and New Haven, CT, a section of track owned by Metro North but shared with Amtrak's Northeast Corridor service, and on third rail between Pelham and Grand Central Terminal. EMUs are used on AMT's Montreal/Deux-Montagnes line. Metro North Railroads New Haven Line runs from New Haven, Connecticut southwest to Woodlawn, New York on the Harlem Line, where New Haven Line trains continue south to Grand Central Terminal in Manhattan. ... The Metro-North Commuter Railroad Company, or MTA Metro-North Railroad, or, more commonly, Metro-North, is a suburban commuter rail service that is run and managed by an authority of New York State, the Metropolitan Transportation Authority, or, more simply, the MTA. Metro-North runs service between New York... The overhead lines of a Swiss Federal Railways track. ... The Pelham Metro-North Railroad station serves the residents of Pelham, New York via the New Haven Line. ... Union Station is the main railroad passenger station in New Haven, Connecticut. ... 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 Agence métropolitaine de transport (AMT) or (English: Metropolitan Transportation Agency) (AAR reporting marks AMT) is the umbrella organization that plans, integrates, and coordinates public transportation services across Canadas Greater Montreal Region, including the Island of Montreal, Laval (ÃŽle Jésus), and communities along both the North Shore... The Deux-Montagnes line is a commuter rail line operated in the Greater Montreal, Quebec, Canada area, by the Agence métropolitaine de transport, or AMT, (in English, the Metropolitan transportation agency), the umbrella organization that plans, integrates, and coordinates public transportation services across this region. ...

DMUs are less common, partly because new light rail operations are almost entirely electric, with many commuter routes already electrified, and also because of the difficulties posed by Federal Railway Administration rules limiting their use on shared passenger/freight corridors. When the Budd RDC was developed following World War II, it was adopted for many secondary passenger routes in the U.S. (especially on the Boston and Maine Railroad) and Canada. These operations generally survived longer in Canada, but several were abandoned in the VIA Rail cutbacks of the early 1990s. One that survives is The Mahalat on Vancouver Island. Budd RDC-1 #407 of the Cape May Seashore Lines. ... 1898 map The Boston and Maine Railroad (AAR reporting marks BM), also known by the abbreviation B&M, was the dominant railroad of the northern New England region of the United States for a century. ... VIA Rails trains travelling by Highway 401 near Brockville, Ontario. ... Malahat or The Malahat refers to an unincorporated district, region, highway, passenger train, and First Nations tribe located on the western side of Saanich Inlet on southern Vancouver Island, British Columbia, Canada. ...

DMUs are used on the RiverLINE in New Jersey. Currently Colorado Railcar is demonstrating an FRA Crash Compliant DMU in the United States. NJ Transit has experimented with this DMU on the Princeton Branch (a.k.a. Princeton "Dinky") line. In August 2006 it was announced that Amtrak wants the State of Vermont to experiment with DMUs on the state-subsidized Vermonter line from New Haven north to St. Albans to replace the less efficient diesel locomotive trainsets currently used. River Line system map The River Line (styled River LINE by NJ Transit) is a light rail system in New Jersey, United States that connects the cities of Camden and Trenton, New Jerseys capital. ... Colorado Railcar is a manufacturer of railroad rolling stock. ... New Jersey Transit Arrow III at West Windsor, NJ Hudson-Bergen Light Rail vehicle at 2nd Street station New Jersey Transit (NJ Transit) is a statewide public transportation system serving the U.S. state of New Jersey. ... Princeton Station at night, August 2004 The Princeton Branch is a branch off of New Jersey Transits Northeast Corridor Line. ... Year 2006 (MMVI) was a common year starting on Sunday (link displays full 2006 calendar) of the Gregorian calendar. ... Union Station is the main railroad passenger terminal in New Haven, Connecticut. ... St. ...

Russia

Main article: Elektrichka

Elektrichka on Yaroslavskiy Rail Terminal, Moscow

Elektrichka (Russian: электри́чка, Ukrainian: електри́чка, elektrychka) is an informal word for elektropoezd (Russian: электропо́езд), a Soviet or post-Soviet regional (mostly suburban) electrical multiple unit passenger train. Elektrichkas are widespread in Russia, Ukraine and some other countries of former Soviet Union. The first elektrichka ride occurred in August 1929 along the line Moscow-Mytishchi. Elektrichka departing from station platform Elektrichka on Yaroslavskiy Rail Terminal, Moscow Elektrichka (Russian: , Ukrainian: is a slang word for elektropoezd (Russian: ), a Soviet or post-Soviet regional (mostly suburban) electrical multiple unit passenger train. ... Image File history File linksMetadata Download high-resolution version (1280x960, 580 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Elektrichka Metadata This file contains additional information, probably added from the digital camera or scanner used to create... Image File history File linksMetadata Download high-resolution version (1280x960, 580 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Elektrichka Metadata This file contains additional information, probably added from the digital camera or scanner used to create... Yaroslavskiy Rail Terminal Yaroslavsky Rail Terminal (Russian: ) is one of the nine railway terminals in Moscow, situated on the Komsomolskaya Square. ... Soviet redirects here. ... Illustration of the backyards of a surburban neighbourhood Suburbs are inhabited districts located either on the outer rim of a city or outside the official limits of a city (the term varies from country to country), or the outer elements of a conurbation. ... A multiple unit is a passenger train whose carriages have their own motors, either diesel (DMUs) or electric (EMUs), and do not need to be hauled by a locomotive. ... It has been suggested that Local trains be merged into this article or section. ... Moscow (Moskva) (Russian: , romanised: Moskva, IPA: see also other names) is the capital of Russia and the countrys economic, financial, educational, and transportation centre. ... Location Position of Mytishchi in Europe Government Country Region District Russia Moscow Oblast Mytishchinskiy Head of Town Settlement Alexandr Kazakov Geographical characteristics Area  - City km² Population  - City (2005) 161,100 Coordinates Time zone - Summer (DST) MSK (UTC+3) MSD (UTC+4) Other Information Dialing Code +7 495 License plate 50...

See also

Wikimedia Commons has media related to:

Category:Multiple units

• Rail terminology
• Pacer (train) units.
• Railcar
• Hybrid Locomotive