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61-572: The MR-73 (Matériel roulant conçu en 1973) is the second generation of rubber-tired rolling stock used on the Montreal Metro . Manufactured by Bombardier Transportation , they entered service in June 1976. Since the retirement of the first generation MR-63s , the MR-73 trains are in use on three of four Montreal's Metro lines. Replacement of the trains is planned for 2036, when they will be 60 years old. In

122-413: A voltage internally. This counter-electromotive force (CEMF) opposes the applied voltage and the current that flows is governed by the difference between the two. As the motor speeds up, the internally generated voltage rises, the resultant EMF falls, less current passes through the motor and the torque drops. The motor naturally stops accelerating when the drag of the train matches the torque produced by

183-592: A drawing of such a railway, with the weight carried by pneumatic main wheels running on a flat board track and guidance provided by small horizontal steel wheels running on the sides of a central vertical guide rail . A similar arrangement was patented by Alejandro Goicoechea , inventor of Talgo , in February 1936, patent ES 141056; in 1973, he built a development of this patent: 'Tren Vertebrado', Patent DE1755198; at Avenida Marítima, in Las Palmas de Gran Canaria . During

244-650: A longer period at the same current level because the lower gears give the motor more mechanical advantage. In diesel-electric and gas turbine-electric locomotives , the horsepower rating of the traction motors is usually around 81% that of the prime mover . This assumes that the electrical generator converts 90% of the engine's output into electrical energy and the traction motors convert 90% of this electrical energy back into mechanical energy. Calculation: 0.9 × 0.9 = 0.81 Individual traction motor ratings usually range up 1,600 kW (2,100 hp). Another important factor when traction motors are designed or specified

305-457: A lower frequency than the commercial supply used for general lighting and power; special traction current power stations are used, or rotary converters used to convert 50 or 60 Hz commercial power to the 25 Hz or 16 + 2 ⁄ 3  Hz frequency used for AC traction motors. Because it permits the simple use of transformers , the AC system allows efficient distribution of power down

366-424: A mechanical or hydraulic transmission system. In the latter part of the 20th century, vehicles with electrical transmission systems (powered by internal combustion engines , batteries, or fuel cells ) began to be developed—one advantage of using electric machines is that specific types can regenerate energy (i.e. act as a regenerative brake )—providing deceleration as well as increasing overall efficiency by charging

427-465: A single central guide rail only. On some systems, such those in Paris, Montreal, and Mexico City, there is a conventional 1,435 mm ( 4 ft  8 + 1 ⁄ 2  in ) standard gauge railway track between the roll ways. The bogies of the train include railway wheels with longer flanges than normal. These conventional wheels are normally just above the rails, but come into use in

488-718: A song performed by the Canadian group "Made Them Lions". Certain shots were captured at the Metros Villa-Maria station for the appearance. Rubber-tyred metro A rubber-tyred metro or rubber-tired metro is a form of rapid transit system that uses a mix of road and rail technology. The vehicles have wheels with rubber tires that run on a roll way inside guide bars for traction. Traditional, flanged steel wheels running on rail tracks provide guidance through switches and act as backup if tyres fail. Most rubber-tyred trains are purpose-built and designed for

549-411: A system can bring the load to a low speed, requiring relatively little friction braking to bring the load to a full stop. On an electric train, the train driver or motorman originally had to control the cutting out of resistance manually, but by 1914, automatic acceleration was being used. This was achieved by an accelerating relay (often called a "notching relay") in the motor circuit which monitored

610-452: A test starts with the motors at +25 °C (and the outside air used for ventilation also at +25 °C). In the USSR, per GOST 2582-72 with class N insulation, the maximum temperatures allowed for DC motors were 160 °C for the armature, 180 °C for the stator, and 105 °C for the collector. The one-hour rating is typically about 10% higher than the continuous rating and is limited by

671-429: A unique three-note sound signature when the train pulls out of a station. The three-note sound is produced by chopper traction motor control equipment, which controls and powers the motors on the train in stages without incurring a power surge. It does so by modulating the current in five consecutive stages (90, 120, 180, 240 and 360 Hz), of which the first two are barely audible over the other noise (fans, wheels) of

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732-594: Is an electric motor used for propulsion of a vehicle, such as locomotives , electric or hydrogen vehicles , or electric multiple unit trains. Traction motors are used in electrically powered railway vehicles ( electric multiple units ) and other electric vehicles including electric milk floats , trolleybuses , elevators , roller coasters , and conveyor systems , as well as vehicles with electrical transmission systems ( diesel–electric locomotives , electric hybrid vehicles ), and battery electric vehicles . Direct-current motors with series field windings are

793-488: Is ideal for starting a train. The disadvantage is that the current flowing into the motor has to be limited, otherwise the supply could be overloaded or the motor and its cabling could be damaged. At best, the torque would exceed the adhesion and the driving wheels would slip. Traditionally, resistors were used to limit the initial current. As the DC motor starts to turn, interaction of the magnetic fields inside causes it to generate

854-412: Is needed. A variant of the DC system is the AC series motor, also known as the universal motor , which is essentially the same device but operates on alternating current . Since both the armature and field current reverse at the same time, the behavior of the motor is similar to that when energized with direct current. To achieve better operating conditions, AC railways are often supplied with current at

915-439: Is operational speed. The motor armature has a maximum safe rotating speed at or below which the windings will stay safely in place. Above this maximum speed centrifugal force on the armature will cause the windings to be thrown outward. In severe cases, this can lead to "birdnesting" as the windings contact the motor housing and eventually break loose from the armature entirely and uncoil. Bird-nesting (the centrifugal ejection of

976-495: Is provided by using pairs of motors on a vehicle in series-parallel control ; for slow operation or heavy loads, two motors can be run in a series of the direct-current supply. Where higher speed is desired, these motors can be operated in parallel, making a higher voltage available at each motor and so allowing higher speeds. Parts of a rail system might use different voltages, with higher voltages in long runs between stations and lower voltages near stations where only slower operation

1037-549: Is supplied from one of the guide bars , which serves as a third rail . The current is picked up by a separate lateral pickup shoe . The return current passes via a return shoe to one or both of the conventional railway tracks , which are part of most systems, or to the other guide bar. Rubber tyres have higher rolling resistance than traditional steel railway wheels. There are some advantages and disadvantages to increased rolling resistance, causing them to not be used in certain countries. Compared to steel wheel on steel rail,

1098-453: Is three-point suspended between the bogie frame and the driven axle; this is referred to as a "nose-suspended traction motor". The problem with such an arrangement is that a portion of the motor's weight is unsprung , increasing unwanted forces on the track. In the case of the famous Pennsylvania Railroad GG1 , two frame-mounted motors drove each axle through a quill drive . The " Bi-Polar " electric locomotives built by General Electric for

1159-474: The Milwaukee Road had direct drive motors. The rotating shaft of the motor was also the axle for the wheels. In the case of French TGV power cars , a motor mounted to the power car's frame drives each axle; a "tripod" drive allows a small amount of flexibility in the drive train allowing the trucks bogies to pivot. By mounting the relatively heavy traction motor directly to the power car's frame, rather than to

1220-573: The World War II German occupation of Paris, the Metro system was used to capacity, with relatively little maintenance performed. At the end of the war, the system was so worn that thought was given as to how to renovate it. Rubber-tyred metro technology was first applied to the Paris Métro , developed by Michelin , who provided the tyres and guidance system, in collaboration with Renault , who provided

1281-496: The MR-63 to assist friction braking. The MR-73's current chopper recuperates energy when in braking mode, turning traction motors into generators and sending a regulated current back into the traction power supply for other trains to use. Electrical braking is most effective when one train draws power while it is starting, and another train at a different location sends power while it is braking. The Mean Distance Between Failures (MDBF) for

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1342-405: The MR-73 exceeded 200,000 mi (322,000 km) in 2004. [REDACTED] Green Line (1976–1985, 2016–present) [REDACTED] Orange Line (1976–2019) [REDACTED] Yellow Line (1976–2008, 2017–present) [REDACTED] Blue Line (1986–present) Formation (as of December 2021) 0 on weekends The MR-73 made a brief cameo appearance in the 2014 music video for "Tidal Wave"

1403-427: The Metro, as well as from an Austrian subsidiary of Bombardier that previously manufactured trams. The 423 MR-73 cars were manufactured at Bombardier's La Pocatière plant between 1974 and 1980 and the first units entered service in 1976. The MR-73's original interior featured orange-and-white seats arranged so that in each third of the train, there were two double sets of transverse seating and four single seats near

1464-405: The advantages of rubber-tyred metro systems are: The higher friction and increased rolling resistance cause disadvantages (compared to steel wheel on steel rail): Although it is a more complex technology, most rubber-tyred metro systems use quite simple techniques, in contrast to guided buses . Heat dissipation is an issue as eventually all traction energy consumed by the train — except

1525-403: The armature and the field windings are connected in series, the whole motor is referred to as "series-wound". A series-wound DC motor has a low resistance field and armature circuit. For this reason, when voltage is applied to it, the current is high due to Ohm's law . The advantage of high current is that the magnetic fields inside the motor are strong, producing high torque (turning force), so it

1586-436: The armature assembly and winding supports and retainers have been damaged by the previous abuse. Because of the high power levels involved, traction motors are almost always cooled using forced air, water or a special dielectric liquid . Typical cooling systems on U.S. diesel-electric locomotives consist of an electrically powered fan blowing air into a passage integrated into the locomotive frame. Rubber cooling ducts connect

1647-425: The armature's windings) due to overspeed can occur either in operating traction motors of powered locomotives or in traction motors of dead-in-consist locomotives being transported within a train traveling too fast. Another cause is replacement of worn or damaged traction motors with units incorrectly geared for the application. Damage from overloading and overheating can also cause bird-nesting below rated speeds when

1708-515: The battery pack. Traditionally, these were series-wound brushed DC motors , usually running on approximately 600 volts. The availability of high-powered semiconductors ( thyristors and the IGBT ) has now made practical the use of much simpler, higher-reliability AC induction motors known as asynchronous traction motors. Synchronous AC motors are also occasionally used, as in the French TGV . Before

1769-459: The bogie, better dynamics are obtained, allowing better high-speed operation. The DC motor was the mainstay of electric traction drives on electric and diesel-electric locomotives, street-cars/trams and diesel electric drilling rigs for many years. It consists of two parts, a rotating armature and fixed field windings surrounding the rotating armature mounted around a shaft. The fixed field windings consist of tightly wound coils of wire fitted inside

1830-451: The case of a flat tyre, or at switches (points) and crossings . In Paris these rails were also used to enable mixed traffic, with rubber-tyred and steel-wheeled trains using the same track, particularly during conversion from normal railway track. The VAL system, used in Lille and Toulouse , has other sorts of flat-tyre compensation and switching methods. On most systems, the electric power

1891-448: The circuit, full line voltage is being applied directly to the motor. The train's speed remains constant at the point where the torque of the motor, governed by the effective voltage, equals the drag - sometimes referred to as balancing speed. If the train starts to climb an incline, the speed decreases because drag is greater than torque and the reduction in speed causes the CEMF to fall and thus

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1952-606: The door closing sound for the Montréal Metro and as brand sound for the entire STM. A prototype for the current chopper was built by the Canron company using a Jeumont original design in the early 1970s on an MR-63 train. Until the retirement of the MR–63s in 2018, one of the three elements of the "Jeumont Train" were operated on the Green Line among rheostatic-started MR-63s; one of these

2013-430: The doors in longitudinal formation. In the early 1990s, Alstom Télécité LED visual information screens were added on top of alternating side windows in all MR-73 cars. Advertisements were displayed, along with information on the weather and upcoming stations. Around the same time, automated next-station announcements were introduced on the MR-73 and voiced by Judith Ouimet . In December 2005, work began to refurbish

2074-506: The early 1970s, the Commission de transport de la Communauté urbaine de Montréal (CTCUM), the predecessor of the STM , identified a need for more rolling stock to serve the crowds expected for the 1976 Summer Olympics and for future network expansions. Mayor of Montreal Jean Drapeau suggested to snowmobile manufacturer Bombardier that they should bid on the contract. Although the design of what

2135-528: The effective voltage to rise - until the current through the motor produces enough torque to match the new drag. The use of series resistance was wasteful because a lot of energy was lost as heat. To reduce these losses, electric locomotives and trains (before the advent of power electronics ) were normally equipped for series-parallel control as well. Locomotives that operated from AC power sources (using universal motors as traction motors) could also take advantage of tap changers on their transformers to vary

2196-406: The electric energy regenerated back into the substation during electrodynamic braking  — will end up in losses (mostly heat). In frequently operated tunnels (typical metro operation) the extra heat from rubber tyres is a widespread problem, necessitating ventilation of the tunnels. As a result, some rubber-tyred metro systems do not have air-conditioned trains, as air conditioning would heat

2257-473: The fall of current as each step of resistance was cut out. All the driver had to do was select low, medium or full speed (called "series", "parallel" and "shunt" from the way the motors were connected in the resistance circuit) and the automatic equipment would do the rest. Electric locomotives usually have a continuous and one-hour rating. The one-hour rating is the maximum power that the motors can continuously develop over one hour without overheating. Such

2318-485: The field current is reduced by the back-EMF in a series wound motor, there is no speed at which the back-EMF will exceed the supply voltage, and therefore a single series wound DC traction motor alone cannot provide dynamic or regenerative braking. There are, however various schemes applied to provide a retarding force using the traction motors. The energy generated may be returned to the supply (regenerative braking), or dissipated by on board resistors (dynamic braking). Such

2379-759: The first car of the series, 79-501, was returned to the La Pocatière plant, now owned by Bombardier's successor Alstom . In 2022, STM announced they planned to replace the trains in the 2030s, with work underway to purchase new trains. This was estimated to cost around $ 2.9bn. The STM also noted that to increase the capacity of the Green Line by 37%, works to upgrade garages and signalling systems would be required as well as new rolling stock. The MR-73 cars can be identified by rectangular cab headlights, side vents, blue and dark orange interiors, and 174 kW (233 hp) traction motors that growl while accelerating, producing

2440-403: The frequency of the AC power supply. The advent of power semiconductors has made it possible to fit a variable frequency drive on a locomotive; this allows a wide range of speeds, AC power transmission, and the use of rugged induction motors that do not have wearing parts like brushes and commutators. Traditionally road vehicles (cars, buses, and trucks) have used diesel and petrol engines with

2501-454: The heaviest traffic load of all Paris Métro lines. Finally, Line 6 Charles de Gaulle – Étoile – Nation was converted in 1974 to reduce train noise on its many elevated sections. Because of the high cost of converting existing rail-based lines, this is no longer done in Paris, or elsewhere. Now, rubber-tyred metros are used in new systems or lines only, including the new Paris Métro Line 14 . The first completely rubber-tyred metro system

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2562-431: The length of a rail line, and also permits speed control with switchgear on the vehicle. AC induction motors and synchronous motors are simple and low maintenance, but up until the advent of power semiconductors , were awkward to apply for traction motors because of their fixed speed characteristic. An AC induction motor generates useful amounts of power only over a narrow speed range determined by its construction and

2623-508: The metro, but the last three clearly audible. These choppers give the MR-73 an initial rate of acceleration of 1.43 m/s (4.7 ft/s) (5.2 km/(h⋅s) or 3.2 mph/s). The notes of the propulsion are the same as the first three notes of Aaron Copland 's " Fanfare for the Common Man ", one of the musical themes for Expo 67 , but that is apparently just a coincidence. The notes were so remarkable, that in 2010 these notes were chosen as

2684-473: The mid-20th century, a single large motor was often used to drive multiple driving wheels through connecting rods that were very similar to those used on steam locomotives . Examples are the Pennsylvania Railroad DD1 , FF1 and L5 and the various Swiss Crocodiles . It is now standard practice to provide one traction motor driving each axle through a gear drive. Usually, the traction motor

2745-403: The motor case. The armature is another set of coils wound round a central shaft and is connected to the field windings through "brushes" which are spring-loaded contacts pressing against an extension of the armature called the commutator . The commutator collects all the terminations of the armature coils and distributes them in a circular pattern to allow the correct sequence of current flow. When

2806-454: The motors. To continue accelerating the train, series resistors are switched out step by step, each step increasing the effective voltage and thus the current and torque for a little bit longer until the motor catches up. This can be heard and felt in older DC trains as a series of clunks under the floor, each accompanied by a jerk of acceleration as the torque suddenly increases in response to the new surge of current. When no resistors are left in

2867-457: The now 30 year old trains. The trains were still very reliable, with a Mean Distance Between Failures (MDBF) exceeding 200,000 mi (322,000 km) in 2004. The MR-73 fleet underwent a $ 40 million refurbishment to reconfigure interior seating to increase total car capacity and install new poles and new panels with a new ergonomic colour scheme that discouraged vandalism, decreased motion sickness, and promoted aesthetic harmony. Seating capacity

2928-401: The oldest type of traction motors. These provide a speed-torque characteristic useful for propulsion, providing high torque at lower speeds for the acceleration of the vehicle, and declining torque as speed increases. By arranging the field winding with multiple taps, the speed characteristic can be varied, allowing relatively smooth operator control of acceleration. A further measure of control

2989-446: The system on which they operate. Guided buses are sometimes referred to as ' trams on tyres', and compared to rubber-tyred metros. The first idea for rubber-tyred railway vehicles was the work of Scotsman Robert William Thomson , the original inventor of the pneumatic tyre . In his patent of 1846 he describes his 'Aerial Wheels' as being equally suitable for, "the ground or rail or track on which they run". The patent also included

3050-409: The temperature rise in the motor. As traction motors use a reduction gear setup to transfer torque from the motor armature to the driven axle, the actual load placed on the motor varies with the gear ratio. Otherwise "identical" traction motors can have significantly different load rating. A traction motor geared for freight use with a low gear ratio will safely produce higher torque at the wheels for

3111-902: The tunnels to temperatures where operation is not possible. Automated driverless systems are not exclusively rubber-tyred; many have since been built using conventional rail technology, such as London's Docklands Light Railway , the Copenhagen metro and Vancouver's SkyTrain , the Hong Kong Disneyland Resort line , which uses converted rolling stocks from non-driverless trains, as well as AirTrain JFK , which links JFK Airport in New York City with local subway and commuter trains. Most monorail manufacturers prefer rubber tyres. Rubber-tired systems are as follows, as of 2023 : Siemens Cityval (B) Traction motor A traction motor

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3172-529: The vehicles. Starting in 1951, an experimental vehicle, the MP 51 , operated on a test track between Porte des Lilas and Pré Saint Gervais, a section of line not open to the public. Line 11 Châtelet – Mairie des Lilas was the first line to be converted, in 1956, chosen because of its steep grades . This was followed by Line 1 Château de Vincennes – Pont de Neuilly in 1964, and Line 4 Porte d'Orléans – Porte de Clignancourt in 1967, converted because they had

3233-414: The voltage applied to the traction motors without the losses inherent in resistors. The Pennsylvania Railroad class GG1 was an example of such a locomotive. If the train starts to descend a grade, the speed increases because the (reduced) drag is less than the torque. With increased speed, the internally generated back-EMF voltage rises, reducing the torque until the torque again balances the drag. Because

3294-496: The width of a tyre, which are made of various materials. The Montreal Metro, Lille Metro , Toulouse Metro , and most parts of Santiago Metro, use concrete . The Busan Subway Line 4 employs a concrete slab . The Paris Métro, Mexico City Metro, and the non-underground section of Santiago Metro, use H-Shaped hot rolled steel , and the Sapporo Municipal Subway uses flat steel . The Sapporo system and Lille Metro use

3355-634: Was built in Montreal , Quebec, Canada, in 1966. The trains of the Santiago and Mexico City Metros are based on those of the Paris Métro . A few more recent rubber-tyred systems have used automated, driverless trains; one of the first such systems, developed by Matra , opened in 1983 in Lille , and others have since been built in Toulouse and Rennes . Paris Metro Line 14 was automated from its beginning (1998), and Line 1

3416-587: Was converted to automatic in 2007–2011. The first automated rubber-tyred system opened in Kobe , Japan, in February 1981. It is the Port Liner linking Sannomiya railway station with Port Island. Trains are usually in the form of electric multiple units . Just as on a conventional railway, the driver does not have to steer, with the system relying on some sort of guideway to direct the train. The type of guideway varies between networks. Most use two parallel roll ways , each

3477-410: Was much louder than the other. They are the only two to exhibit the whole five-note audible signature in normal operation even though it is possible to hear them during longer-than-usual starts on regular MR-73s. Some MR-73s originally sported murals of Montreal at the end of the cars; however, they were damaged by vandalism and removed long ago. The MR-73 has a different electrical braking system from

3538-462: Was reduced by six per carriage, increasing standing room. The refurbishment also include an ergonomic full-spectrum lighting system that provides therapeutic anti-depression effects for its passengers. Like the older MR-63 fleet, the MR-73 driver cabs was modernized and equipped with ergonomic features and digital dashboards. Work was completed in 2008. In 2006, an MR-73 train was tested with a four-beep door chime, and in 2008, another high-pitched chime

3599-505: Was soon removed, however, and since 2012, the MR-73s play the three-note sequence whenever the doors are about to close. The STM noted in 2014 that they planned for the fleet to remain in service until at least 2036. As of 2023, the oldest MR-73 cars are 47 years old. The less reliable cars have been retired, with 63 cars scrapped from June 2021 to make room for the MPM-10 Azur . In June 2021,

3660-402: Was tested. However, the new chimes were unpopular and so in 2010, a three-note sequence that is essentially replicating the last three audible notes from the electric chopper control traction system was tested, along with a voiceover by Michèle Deslauriers saying Attention, nous fermons les portes (Attention, we are closing the doors) after the three-note sound was played. The voiceover portion

3721-567: Was to later become the MR-73 was completed in 1973, it was only in 1974 that the CTCUM formally awarded the MR-73 contract to the fledgling Bombardier Transportation . A cheaper bid by Canadian Vickers , manufacturer of the MR-63 trains, was disqualified by a technicality. Bombardier had never manufactured a Metro train in Canada, and assistance was sought from SOFRETU , the French consultants who helped design

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