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77-418: EMUs are popular on commuter, and suburban rail networks around the world due to their fast acceleration and pollution-free operation, and are used on most rapid-transit systems. Being quieter than diesel multiple units (DMUs) and locomotive -hauled trains, EMUs can operate later at night and more frequently without disturbing nearby residents. In addition, tunnel design for EMU trains is simpler as no provision

154-499: A diesel engine drives an electrical generator or an alternator which produces electrical energy . The generated current is then fed to electric traction motors on the wheels or bogies in the same way as a conventional diesel–electric locomotive . On some DEMUs, such as the Bombardier Voyager , each car is entirely self-contained and has its own engine, generator and electric motors. In other designs, such as

231-628: A WDM-2 or WDM-3A locomotive in the middle. These old trains had the loco controls duplicated in the Driving Trailer coach and all the actuation information reaching the locomotive through thin communication lines. This was called 'push-pull train'. The longest running such push-pull service operated between Diva – Bhiwandi Road and Vasai Road and was recently converted into an MEMU train service in 2018. India's first and largest DMU shed at Jalandhar , Punjab, holds more than 90 units placed in service all over Punjab. First generation DMU: Rated power

308-546: A bi-mode multiple units train (BMU), just adding one or two pantographs or contact shoes (with opportune converters, if necessary) and related modifications on the electric system. NMBS/SNCB uses its NMBS/SNCB Class 41 DMUs on the few remaining unelectrified lines. As electrification progresses, the DMUs become less and less important. Diesel multiple units cover large number of passenger lines in Croatia which are operated by

385-770: A commuter rail system in Johannesburg , operates with Bombardier Electrostar electric multiple units. The concept of multiple unit has entered the horizon of the Chinese since the 6th Speed-up Campaign of China Railway in 2007. With the upgrade of Jinghu Railway , North Jingguang Railway , Jingha Railway and Hukun Railway , and the construction of new Passenger Dedicated Lines (or Passenger Railways) completed, CRH (China Railway High-speed) trains have been put into service, mainly in North and Northeast China, and East China. All these CRH trains are electric multiple units. This

462-411: A diesel–hydraulic multiple unit (DHMU), a hydraulic torque converter , a type of fluid coupling, acts as the transmission medium for the motive power of the diesel engine to turn the wheels. Some units feature a hybrid mix of hydraulic and mechanical transmissions, usually reverting to the latter at higher operating speeds as this decreases engine RPM and noise. In a diesel–electric multiple unit (DEMU),

539-612: A locomotive hauled service. Today, DMUs are widely used throughout Australia's southern states: In Queensland, heritage DMUs are used on the Savannahlander and Gulflander tourist trains. Chinese manufactured (CNR Tangshan) DEMU was introduced in Bangladesh from 25 May 2013. DEMU is the country's first-ever commuter train service starting its journey on the Chittagong–Fouzdarhat line. These DEMUs also operate on

616-401: A locomotive-drawn train. This is not so easy for a multiple unit, since individual cars can be attached or detached only in a maintenance facility. This also allows a loco-hauled train to be flexible in terms of number of cars. Cars can be removed or added one by one, but on multiple units two or more units have to be coupled. This is not so flexible. The passenger environment of a multiple unit

693-528: A locomotive-hauled train, if the number of cars is changed to meet the demand, acceleration and braking performance will also change. This calls for performance calculations to be done taking the heaviest train composition into account. This may sometimes cause some trains in off-peak periods to be overpowered with respect to the required performance. When 2 or more multiple units are coupled, train performance remains almost unchanged. However, in locomotive-hauled train compositions, using more powerful locomotives when

770-568: A locomotive-hauled train, one crew can serve the train regardless of the number of cars in the train provided limits of individual workload are not exceeded. Likewise, in such instances, buffet cars and other shared passenger facilities may need to be duplicated in each unit, reducing efficiency. Large locomotives can be used instead of small locomotives where more power is needed. Also, different types of passenger cars (such as reclining-seats, compartment cars, couchettes, sleepers, restaurant cars, buffet cars, etc.) can be easily added to or removed from

847-405: A motor or trailer car, it is not necessary for every one to be motorized. Trailer cars can contain supplementary equipment such as air compressors, batteries, etc.; they may also be fitted with a driving cab. In most cases, MU trains can only be driven/controlled from dedicated cab cars. However, in some MU trains, every car is equipped with a driving console, and other controls necessary to operate

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924-474: A semi-high-speed EMU named Vande Bharat Express , capable of running at 183 km/h (114 mph). And it continues to use diesel and electrical multiple units on its national network. All suburban and rapid transit lines are served by EMUs. Indonesia uses diesel since 1976 and electric MUs since 1925. Most of these MUs were built in Japan. The Manila Railroad Company (MRR) acquired its first multiple units in

1001-444: A single train, then be broken at a junction point into shorter trains for different destinations. As there are multiple engines/motors, the failure of one engine does not prevent the train from continuing its journey. A locomotive-drawn train typically has only one power unit, whose failure will disable the train. However, some locomotive-hauled trains may contain more than one power unit and thus be able to continue at reduced speed after

1078-527: A train is longer can solve this problem. It may be easier to maintain one locomotive than many self-propelled cars. 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 casualties than one with a locomotive (where the heavy locomotive would act as a "crumple zone"). If a locomotive fails, it can be easily replaced with minimal shunting movements. There would be no need for passengers to evacuate

1155-826: 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 the former Soviet Union. The first elektrichka ride occurred in August 1929 between Moscow and Mytishchi . Swedish railroads have been privatized in steps for about 25 years, and today many different companies operate different types of multiple units. A majority of passenger trains today consists of multiple unit trains of which regional traffic exclusively use them. The Swiss Federal Railways use many multiple units, mainly on regional lines ( S-Bahn ). In

1232-478: Is needed for exhausting fumes, although retrofitting existing limited-clearance tunnels to accommodate the extra equipment needed to transmit electric power to the train can be difficult. Multiple unit train control was first used in the 1890s. The Liverpool Overhead Railway opened in 1893 with two-car electric multiple units, controllers in cabs at both ends directly controlling the traction current to motors on both cars. The multiple unit traction control system

1309-517: Is often noticeably noisier than that of a locomotive-hauled train, due to the presence of underfloor machinery. The same applies to vibration. This is a particular problem with DMUs . Separating the motive power from the payload-carrying cars means that either can be replaced when obsolete without affecting the other. Algeria possesses 17 units of the Coradia El Djazaïr, a multiple unit train produced by Alstom. These units are similar to

1386-724: The British Rail Class 207 or the Stadler GTW and Stadler FLIRT DMU , some cars within the consist may be entirely unpowered or only feature electric motors, obtaining electric current from other cars in the consist which have a generator and engine. With diesel–electric transmission, some DMU can be no other than an EMU without pantograph or contact shoes (for use on the former British Rail Southern Region ), which "is substituted" by one or more on-board diesel generators ; this kind of DEMU can be potentially upgraded to electro-diesel multiple unit (EDMU), becoming

1463-779: The China Railway High-speed in China, ICE 3 in Germany, and the British Rail class 395 Javelin. The retired New York–Washington Metroliner service, first operated by the Pennsylvania Railroad and later by Amtrak , also featured high-speed electric multiple-unit cars, known as the Budd Metroliner . EMUs powered by fuel cells are under development. If successful, this would avoid

1540-603: The Chittagong Circular Railway and on the Bangladesh Railway 's service between Dhaka and Narayanganj . Mexican manufacturer Ferrovias Del Bajio supplied in 2019, three DSUs (Diesel Single Unit) to Royal Railway in Cambodia for their airport shuttle service from Phnom Penh international airport to the city central station. The other two units were assigned to long-distance services from

1617-586: The LRT Line 1 built by La Brugeoise et Nivelles in Belgium . The first EMUs to be used outside of rapid transit will enter service between 2021 and 2022. Most trains in North America are locomotive-hauled and use Multiple Unit (MU) control to control multiple locomotives. The control system of the leading locomotive connects to the other locomotives so that the engineer's control is repeated on all

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1694-622: The South Side Elevated Railroad (now part of the Chicago 'L' ) in 1897. In 1895, derived from his company's invention and production of direct-current elevator control systems, Frank Sprague invented a multiple-unit controller for electric train operation. This accelerated the construction of electric-traction railways and trolley systems worldwide. Each car of the train has its own traction motors: by means of motor control relays in each car energized by train-line wires from

1771-518: The national railways ) had been built since the 1920s, the first two streamlined DMUs came in service in 1937, class Kiha 43000 (キハ43000系). The service of several hundreds (in sum even thousands) of diesel railcars and DMUs started in 1950s following the improvement of fuel supply that was critical during World War II . In 2021, Kenya acquired DMUs from France to operate in the Nairobi Metropolitan Area. These trains connect

1848-497: The ČSD used the series designations proposed by Vojtěch Kryšpín , and vehicles created after this date, which no longer have Kryšpín's designations (with some exceptions). In addition, these new cars are the new vehicles are already different in both countries. Elron has since 2015 a Stadler FLIRT fleet, with 20 trains DEMU version. Germany has employed DMUs for both commuter and express services for many decades. The SVT 877 Fliegender Hamburger DMU, introduced in 1933, made

1925-849: The 1930s. The locally-built MC class was initially powered by gasoline and was changed to diesel during World War II . Both the MRR and its successor, the Philippine National Railways (PNR), has since acquired various classes of diesel multiple units. All multiple units owned by MRR and all of the older MUs of the PNR were built by Japanese firms. On the other hand, its newer rolling stock were built in South Korea and Indonesia . There will also be DMUs that will be built in China . The first electric multiple units were acquired in 1984 for

2002-539: The 1950s, but by utilizing and enhancing the technology of short-distance urban MU trains, long-distance express MU-type vehicles were developed and widely introduced starting in the mid-1950s. This work resulted in the original Shinkansen development which optimized all of the EMU's efficiencies to maximize speed. It was introduced upon completion of the Tokaido Shinkansen (literally "new trunk line") in 1964. By

2079-486: The 1970s, locomotive traction was regarded as slow and inefficient, and its use is now mostly limited to freight trains. From 1999, there have been development efforts in freight EMU technology, but it is currently used only for an express freight service on the Tokaido Main Line between Tokyo and Osaka. The government has been pushing for the adoption of freight EMU technology on energy efficiency grounds in

2156-883: The Adtranz Class 612 tilting train ("Regio Swinger"), the Alstom Coradia LINT (Classes 620–623, 640 and 648), the Siemens Desiro (Class 642) and the Bombardier Talent (Class 643/644). From 2001 to 2016 there was even a DMU version of DB's high-speed Intercity Express , the Class 605 ICE TD . In the Republic of Ireland the Córas Iompair Éireann (CIÉ), which controlled the republic's railways between 1945 and 1986, introduced DMUs in

2233-474: The Czech Republic which are operated by the national operator České dráhy . They have important role since they cover local, regional and distant lines all across the country. Those trains may also cover other lines in the country depending on need and availability too. Also, the DMUs were manufactured for foreign carriers. The tables of cars and units are divided into vehicles operated until 1987, when

2310-471: The FRA. This has greatly restricted the development of DMUs within the U.S. as no other country requires the much heavier FRA compliant vehicles, and no export market for them exists. Operations using FRA-compliant vehicles: Operations using non FRA-compliant vehicles: Proposed operations: DMUs were first introduced to Australia in the late mid-20th century for use on quiet branch lines that could not justify

2387-603: The French version of Régiolis, which belongs to the Coradia family. Metrorail , which provides commuter rail service in major urban areas of South Africa, operates most services using electric multiple unit train sets of the type 5M2A . These trains are being gradually refurbished and subsequently designated as 10M3 (Cape Town), 10M4 (Gauteng) or 10M5 (Durban). Metrorail services are split into four regions; Gauteng , KwaZulu-Natal , Eastern Cape and Western Cape . Gautrain ,

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2464-1009: The Japanese Shinkansen and the German Intercity-Express ICE 3 high-speed trains . A new high-speed MU, the AGV , was unveiled by France's Alstom on 5 February 2008. It has a claimed service speed of 360 km/h (220 mph). India's ICF announced the country's first high-speed engine-less train named 'train 18', which would run at 250 km/h maximum speed. Multiple units have been occasionally used for freight traffic, such as carrying containers or for trains used for maintenance. The Japanese M250 series train has four front and end carriages that are EMUs, and has been operating since March 2004. The German CargoSprinter have been used in three countries since 2003. They are more energy-efficient than locomotive-hauled trains. They have better adhesion , as more of

2541-709: The PNR in the island of Luzon . Even without active inter-city rail services in the present-day, DMUs are still used on the PNR Metro Commuter Line in Metro Manila and the Bicol Commuter service in the Bicol Region . Three generations of DMUs are in use: second-hand DMUs handed over by JR East such as the KiHa 35 , 52 and 59 series originally built in the 1960s and acquired in

2618-707: The Slovenská strela motor express train led on the Bratislava-Prague route by a motor car of the same name, or the Tatran express from Bratislava to Košice. Representatives of high-speed motor wagons were, for example, motor wagons of the M262 or M286 series, which, however, lost their application in high-speed wagons due to the gradual electrification of main lines and were, like the current wagons currently used for passenger trains. The first significant use of DMUs in

2695-666: The U.S. was the Budd Rail Diesel Car (RDC). The RDC was a single passenger car with two diesel engines and two sets of controls. In the United States, DMU systems must be FRA-compliant to be permitted on freight rail corridors. The Federal Railway Administration has mandated higher coupling strength requirements than European regulators, effectively prohibiting the use of lighter weight European-style inter-city rail DMUs on U.S. main line railways without timesharing with freight operations or special waivers from

2772-721: The UK the use of modern diesel multiple units was pioneered in Northern Ireland, although a number of other railway companies also experimented with early DMUs (including the Great Western and the London Midland Scottish). Notable examples include the Sprinter and Voyager families, and the newer Javelin trains. The London Underground passenger system is operated exclusively by EMUs. Work trains on

2849-530: The US, but new services are evaluated on a case-by-case basis. As a result, several types of lightweight DMUs have been used: Costa Rica has purchased several Apolo 2400 series DMU railcars from the former narrow gauge operator in Spain, which are run in commuter service. 42 X'Trapolis Tsíimin K'áak train sets have been ordered for Tren Maya , 10 of which are DMU and 32 are EDMU. A type of diesel multiple units in

2926-993: The Underground employ separate locomotives, some of which are dual battery/live rail powered. 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). The first multiple unis in Australia were the Tait trains, wooden bodied Electric Multiple Unit train that operated in Melbourne , Victoria . They were originally introduced as steam locomotive hauled carriages but were converted to electric traction from 1919 during Melbourne’s electrification project. Indian Railways has recently introduced

3003-650: The United Kingdom was by the Great Western Railway , which introduced its small but successful series of diesel–mechanical GWR railcars in 1934. The London & North Eastern Railway and London, Midland & Scottish Railway also experimented with DMUs in the 1930s, the LMS both on its own system , and on that of its Northern Irish subsidiary , but development was curtailed by World War II . After nationalisation, British Railways (BR) revived

3080-422: The batteries are charged via the electric pickup when operating on electric mode. EMUs, when compared with electric locomotives , offer: Electric locomotives, when compared to EMUs, offer: Diesel multiple unit A diesel multiple unit or DMU is a multiple-unit train powered by on-board diesel engines . A DMU requires no separate locomotive , as the engines are incorporated into one or more of

3157-435: The carriages. Diesel-powered single-unit railcars are also generally classed as DMUs. Diesel-powered units may be further classified by their transmission type: diesel–mechanical DMMU , diesel–hydraulic DHMU , or diesel–electric DEMU . The diesel engine may be located above the frame in an engine bay or under the floor. Driving controls can be at both ends, on one end, or in a separate car. DMUs are usually classified by

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3234-420: The cars that make up the unit. In many cases these cars can only propel themselves when they are part of the unit, so they are semi-permanently coupled. For example, in a DMU one car might 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. MU cars can be

3311-523: The central station to Sihanoukville and to Poipet. Royal Railways Cambodia have now acquired eleven carriages DMU from Japan. Model: " Kiha 183 heavy snow ". (キハ183系オホーツク・大雪) Speed: 110 km/h (max) Type: 特急　(Limited Express) Started: 1986 ............ End of Service in Japan 17 March 2023 DMUs (DEMUs) are widely used in India. DEMUs in India are used in both the eight-coach format and the four-coach format. These trains replaced many (up to 10 car) trains with

3388-666: The city with settlements outside Nairobi, Jomo Kenyatta International Airport and the Nairobi Terminus. The Keretapi Tanah Melayu (KTM) has a total of 13 DMU KTM Class 61 ordered from CRRC for the West Coast Line and are assembled locally at CRRCs Batu Gajah factory from 2016 to 2020. The first scheduled service is expected from 1 September along the Gemas-Johor Bahru route, replacing old non-automotive stock. The Philippine National Railways (PNR)

3465-418: The concept in the early 1950s. At that time there was an urgent need to move away from expensive steam traction which led to many experimental designs using diesel propulsion and multiple units . The early DMUs proved successful, and under BR's 1955 Modernisation Plan the building of a large fleet was authorised. These BR "First Generation" DMUs were built between 1956 and 1963. BR required that contracts for

3542-679: The costly motive power assets can be moved around as needed and also used for hauling freight trains. A multiple unit arrangement would limit these costly motive power resources to use in passenger transportation. It is difficult to have gangway connections between coupled units and still retain an aerodynamic leading front end. Because of this, there is usually no passage between high-speed coupled units, though lower-speed coupled units frequently have connections between coupled units. This may require more crew members, so that ticket inspectors, for example, can be present in all of them. This leads to higher operating costs and lower use of crew resources. In

3619-587: The country depending on need and availability. Luxury DMU series 7021 , built in France , started to operate for Yugoslav Railways in 1972 and after 1991 still remained in service of Croatian Railways until 2005. Units 7121 and 7122 (which came as a replacement for 7221 units), together with the newest series 7022 and 7023 built in 2010s Croatia, cover many of the country's local and regional services on unelectrified or partly electrified lines. Diesel multiple units also cover large number of passenger lines in

3696-408: The design and manufacture of new locomotives and rolling stock be split between numerous private firms as well as BR's own workshops, while different BR Regions laid down different specifications. The result was a multitude of different types, one of which was: In 1960, British Railways introduced its Blue Pullman high-speed DEMUs. These were few in number and relatively short-lived, but they paved

3773-806: The early 2010s, the Rotem DMUs of 2009 built by Korean manufacturer Hyundai Rotem , and the 8000 and 8100 classes built by Indonesian firm PT INKA . Multiple-unit A multiple-unit train (or multiple unit ( MU )) is a self-propelled train composed of one or more carriages joined, which if coupled to another multiple unit can be controlled by a single driver, with multiple-unit train control . Although multiple units consist of several carriages, single self-propelled carriages – also called railcars , rail motor coaches or railbuses – are in fact multiple units when two or more of them are working connected through multiple-unit train control (regardless of whether passengers can walk between

3850-503: The energy consumed for accelerating the train increases significantly with an increase in weight. Because of the energy efficiency and higher adhesive-weight-to-total-weight ratio values, they generally have higher acceleration ability than locomotive-type trains and are favored in urban trains and metro systems for frequent start/stop routines. Most of them have cabs at both ends, resulting in quicker turnaround times, reduced crewing costs, and enhanced safety. The faster turnaround time and

3927-510: The failure of one. They have lighter axle loads, allowing operation on lighter tracks, where locomotives may be banned. Another side effect of this is reduced track wear, as traction forces can be provided through many axles, rather than just the four or six of a locomotive. They generally have rigid couplers instead of the flexible ones often used on locomotive-hauled trains. That means brakes/throttle can be more quickly applied without an excessive amount of jerk experienced in passenger coaches. In

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4004-451: The front car, all the traction motors in the train are controlled in unison. Most MUs are powered either by traction motors , receiving their power through a third rail or overhead wire ( EMU ), or by a diesel engine driving a generator producing electricity to drive traction motors. A MU has the same power and traction components as a locomotive , but instead of the components being concentrated in one car, they are spread throughout

4081-474: The high acceleration ability and quick turnaround times of MUs have advantages, encouraging their development in this country. Additionally, the mountainous terrain gives the MUs an advantage on grades steeper than those found in most countries, particularly on small private lines many of which run from coastal cities to small towns in the mountains. Most long-distance trains in Japan were operated by locomotives until

4158-594: The hope that widespread adoption could assist in meeting CO 2 emissions targets. The effort has been principally targeted at express package shipping that would otherwise travel by road. The first EMUs have been introduced in Belgium in the 1930s. Several models have followed since then, such as the AM75 . CIÉ introduced its first DMUs , the 2600-class, in 1951. Elektrichka ( Russian : электри́чка , Ukrainian : електри́чка , romanized :  elektrychka )

4235-442: The locomotive-hauled passenger services still in operation, the majority are tourist-oriented, such as the numerous steam-hauled trains operated seasonally on scenic lines throughout the country, as well as some of the luxury cruise trains. Japan is a country of high population density with a large number of railway passengers in relatively small urban areas, and frequent operation of short-distance trains has been required. Therefore,

4312-422: The method of transmitting motive power to their wheels. In a diesel–mechanical multiple unit (DMMU), the rotating energy of the engine is transmitted via a gearbox and driveshaft directly to the wheels of the train, like a car . The transmissions can be shifted manually by the driver, as in the great majority of first-generation British Rail DMUs, but in most applications, gears are changed automatically. In

4389-478: The mid '80s, British Rail embarked upon its so called "Sprinterisation" programme, to replace most of the first generation DMUs and many locomotive-hauled trains with three new families of DMU: Following the impact of the privatisation of British Rail in the late 1990s, several other DMU families have been introduced: In 2018, the first bi and tri-mode electro-diesel multiple units were introduced: Canada generally follows similar buffer strength requirements to

4466-591: The mid-1950s and they were the first diesel trains on many main lines. DMUs are used mostly on shorter or less frequently travelled routes in remote areas. The national railway company CFR still uses, along with other DMU models, Class 77 and 78 DMUs, locally built by Malaxa between the 1930s and 50s and refurbished in the 70s. The main DMU in use is the Class 96 Siemens Desiro aka Săgeata Albastră (The Blue Arrow). Private operators also largely use DMU units, mainly purchased from various French and German operators. In

4543-417: The national passenger service operator HŽ Putnički Prijevoz . On Croatian Railways, DMUs have important role since they cover local, regional and distant lines all across the country. The country's two largest towns, Zagreb and Split , are connected with an inter-city service that is provided by DMU tilting trains " RegioSwinger " (Croatian series 7123) since 2004. Those trains may also cover other lines in

4620-415: The need for an overhead line or third rail . An example is Alstom ’s hydrogen -powered Coradia iLint . The term hydrail has been coined for hydrogen-powered rail vehicles. Many battery electric multiple units are in operation around the world, with the take up being strong. Many are bi-modal taking energy from onboard battery banks and line pickups such as overhead wires or third rail. In most cases

4697-501: The outer end of the pair, saving space and expense over a cab at both ends of each car. Disadvantages include a loss of operational flexibility, as trains must be multiples of two cars, and a failure on a single car could force removing both it and its partner from service. Some of the more famous electric multiple units in the world are high-speed trains: the Italian Pendolino and Frecciarossa 1000 , Shinkansen in Japan,

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4774-416: The outer vehicles usually carry the pick up shoes with the motor vehicles receiving the current via intra-unit connections . Many modern two-car EMU sets are set up as twin or "married pair" units. While both units in a married pair are typically driving motors, the ancillary equipment (air compressor and tanks, batteries and charging equipment, traction power and control equipment, etc.) are shared between

4851-562: The power cars were later reclassified as locomotives under Class 43 . HSTs started being replaced in 2017, but as of October 2022 some are still in use. By the early 1980s, many of the surviving First Generation units were reaching the end of their design life, leading to spiralling maintenance costs, poor reliability and a poor public image for the railway. A stopgap solution was to convert some services back to locomotive haulage, as spare locomotives and hauled coaching stock were available, but this also increased operating costs. Commencing in

4928-588: The present, several types of DMUs operate in Slovakia. Was the most common type in Slovakia is a Class 812 ZSSK based on the ČD Class 810 . These are used almost exclusively for hauling passenger trains on non-electrified regional lines and these trains often excel in low travel speeds. In the past, however, in Slovakia there were a number of express trains driven by motor coaches , which often overcame heavier trains driven by steam locomotives at cruising speed, and classic sets. A typical example can be, for example,

5005-540: 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. However, the need to turn a locomotive is no longer a problem for locomotive-hauled trains due to the increasing use of push pull trains . Multiple units may usually be quickly made up or separated into sets of varying lengths. Several multiple units may run as

5082-583: The run from Berlin to Hamburg in an astonishing 138 minutes, and its derivative SVT 137 broke the land speed record in 1936. After World War 2, the VT 11.5 DMU was the flagship of the glamorous Trans Europ Express . Since 1968, DB has designated DMUs with class numbers beginning in 6. While DB and regional transport authorities generally prefer electric power for commuter rail, many local and rural lines remain un-electrified, and DMUs are invaluable in providing services to those areas. DMUs in service as of 2021 include

5159-462: The train has its own traction motors: by means of motor control relays in each car energized by train-line wires from the front car all of the traction motors in the train are controlled in unison. The cars that form a complete EMU set can usually be separated by function into four types: power car, motor car, driving car, and trailer car. Each car can have more than one function, such as a motor-driving car or power-driving car. On third rail systems,

5236-410: The train's weight is carried on driven wheels, rather than the locomotive having to haul the dead weight of unpowered coaches. They have a higher power-to-weight-ratio than a locomotive-hauled train since they don't have a heavy locomotive that does not itself carry passengers, but contributes to the total weight of the train. This is particularly important where train services make frequent stops, since

5313-862: 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. An example of this arrangement is the NJ Transit Arrows. Virtually all rapid-transit rolling stock, such as on the New York City Subway , the London Underground , the Paris Metro and other subway systems, are multiple-units, usually EMUs. Most trains in the Netherlands and Japan are MUs, being suitable for use in areas of high population density. Many high-speed rail trains are also multiple-units, such as

5390-520: The train. Failure of a multiple unit will often require a whole new train and time-consuming switching activities; also passengers would be asked to evacuate the failed train and board another one. However, if the train consists of more than one multiple unit they are often designed such that in the event of the failure of one unit others in the train can tow it in neutral if brakes and other safety systems are operational. Idle trains do not waste expensive motive power resources. Separate locomotives mean that

5467-426: The two cars in the set. Since neither car can operate without its "partner", such sets are permanently coupled and can only be split at maintenance facilities. Advantages of married pair units include weight and cost savings over single-unit cars (due to halving the ancillary equipment required per set) while allowing all cars to be powered, unlike a motor-trailer combination. Each car has only one control cab, located at

5544-404: The units or not). Multiple-unit train control was first used in electric multiple units in the 1890s. The Liverpool Overhead Railway opened in 1893 with two-car electric multiple units, controllers in cabs at both ends directly controlling the traction current to motors on both cars. The multiple-unit traction control system was developed by Frank Sprague and first applied and tested on

5621-440: The way for the very successful InterCity 125 or High Speed Train (HST) units, which were built between 1975 and 1982 to take over most principal express services on non-electrified routes. These 125 mph (201 km/h) trains run with a streamlined power car at each end and (typically) seven to nine intermediate trailer cars. Although originally classified as DEMUs, the trailer cars are very similar to loco-hauled stock, and

5698-633: Was 700 HP and had three or six coaches, made first by ICF. Transmission was Voith-hydraulic. Max speed 100 km/h. Second generation DMU: Rated power is 1400 HP and have eight coaches. Max speed is 105 km/h. Transmission is DC electric. Made at ICF and RCF . Third generation DMU: Rated power is 1,600 HP and have ten coaches. Max speed is 110 km/h. Transmission is AC electric. Made at ICF . State-owned company PT.INKA builds several type of DMU, some of which operate in urban and suburban areas. In Japan, where gasoline-driven railbuses (on small private lines) and railmotors ( Kihani 5000 of

5775-432: Was developed by Frank Sprague and first applied and tested on the South Side Elevated Railroad (now part of the Chicago 'L' ) in 1897. In 1895, derived from his company's invention and production of direct current elevator control systems, Frank Sprague invented a multiple unit controller for electric train operation. This accelerated the construction of electric traction railways and trolley systems worldwide. Each car of

5852-575: Was one of the first adopters of diesel multiple unit trains in Asia. Initially built as gasoline-powered railmotors, the locally assembled Manila Railroad RMC class of 1929 was the first to be powered by diesel traction. Some units were also converted to streamliner units by 1932 for first-class services on the South Main Line between Manila and Legazpi, Albay . Since then, generations of DMUs were used chiefly for short-distance commuter services by

5929-405: Was the beginning of the general service of multiple unit trains in China's national railway system. Far earlier than the introduction of CRH brand, multiple unit trains have been running on all major cities' metro lines in China. In Japan most passenger trains, including the high-speed Shinkansen , are of the multiple-unit (MU) type, with most locomotives now used solely in freight operations. Of

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