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114-403: The Sierra Vista Line was a streetcar route mostly operated by the Pacific Electric Railway . It ran from 1895 to 1951 as the short turn making local stops along the Pasadena Short Line on the outside tracks of the Northern Division quadruple-track system. The line ran from Downtown Los Angeles to the Sierra Vista Junction, at the corner of Huntington Drive and Main Street in

228-413: A block and tackle arrangement. Lines are divided into sections to limit the scope of an outage and to allow maintenance. To allow maintenance to the overhead line without having to turn off the entire system, the line is broken into electrically separated portions known as "sections". Sections often correspond with tension lengths. The transition from section to section is known as a "section break" and

342-509: A streetcar or trolley in the United States) is a type of urban rail transit consisting of either individual railcars or self-propelled multiple unit trains that run on tramway tracks on urban public streets; some include segments on segregated right-of-way . The tramlines or tram networks operated as public transport are called tramways or simply trams/streetcars. Because of their close similarities, trams are commonly included in

456-419: A swing bridge . The catenary wire typically comprises messenger wire (also called catenary wire) and a contact wire where it meets the pantograph. The messenger wire is terminated at the portal, while the contact wire runs into the overhead conductor rail profile at the transition end section before it is terminated at the portal. There is a gap between the overhead conductor rail at the transition end section and

570-603: A tram engine in the UK) at the head of a line of one or more carriages, similar to a small train. Systems with such steam trams included Christchurch , New Zealand; Sydney, Australia; other city systems in New South Wales ; Munich , Germany (from August 1883 on), British India (from 1885) and the Dublin & Blessington Steam Tramway (from 1888) in Ireland. Steam tramways also were used on

684-476: A "Backdoor" connection between different parts, resulting in, amongst other things, a section of the grid de-energised for maintenance being re-energised from the railway substation creating danger. For these reasons, Neutral sections are placed in the electrification between the sections fed from different points in a national grid, or different phases, or grids that are not synchronized. It is highly undesirable to connect unsynchronized grids. A simple section break

798-515: A Vermont blacksmith, had invented a battery-powered electric motor which he later patented. The following year he used it to operate a small model electric car on a short section of track four feet in diameter. Attempts to use batteries as a source of electricity were made from the 1880s and 1890s, with unsuccessful trials conducted in among other places Bendigo and Adelaide in Australia, and for about 14 years as The Hague accutram of HTM in

912-411: A fixed centre point, with the two half-tension lengths expanding and contracting with temperature. Most systems include a brake to stop the wires from unravelling completely if a wire breaks or tension is lost. German systems usually use a single large tensioning pulley (basically a ratchet mechanism) with a toothed rim, mounted on an arm hinged to the mast. Normally the downward pull of the weights and

1026-485: A high electrical potential by connection to feeder stations at regularly spaced intervals along the track. The feeder stations are usually fed from a high-voltage electrical grid . Electric trains that collect their current from overhead lines use a device such as a pantograph , bow collector or trolley pole . It presses against the underside of the lowest overhead wire, the contact wire. Current collectors are electrically conductive and allow current to flow through to

1140-484: A level crossing with the 1,200 V DC Uetliberg railway line ; at many places, trolleybus lines cross the tramway. In some cities, trolleybuses and trams shared a positive (feed) wire. In such cases, a normal trolleybus frog can be used. Alternatively, section breaks can be sited at the crossing point, so that the crossing is electrically dead. Many cities had trams and trolleybuses using trolley poles. They used insulated crossovers, which required tram drivers to put

1254-569: A multiple unit passes over them. In the United Kingdom equipment similar to Automatic Warning System (AWS) is used, but with pairs of magnets placed outside the running rails (as opposed to the AWS magnets placed midway between the rails). Lineside signs on the approach to the neutral section warn the driver to shut off traction power and coast through the dead section. A neutral section or phase break consists of two insulated breaks back-to-back with

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1368-404: A pneumatic servo pantograph with only 3  g acceleration. An electrical circuit requires at least two conductors. Trams and railways use the overhead line as one side of the circuit and the steel rails as the other side of the circuit. For a trolleybus or a trolleytruck , no rails are available for the return current, as the vehicles use rubber tyres on the road surface. Trolleybuses use

1482-415: A return path for the current through their wheels, and must instead use a pair of overhead wires to provide both the current and its return path. To achieve good high-speed current collection, it is necessary to keep the contact wire geometry within defined limits. This is usually achieved by supporting the contact wire from a second wire known as the messenger wire or catenary . This wire approximates

1596-414: A rigid overhead wire in their tunnels, while using normal overhead wires in their above ground sections. In a movable bridge that uses a rigid overhead rail, there is a need to transition from the catenary wire system into an overhead conductor rail at the bridge portal (the last traction current pylon before the movable bridge). For example, the power supply can be done through a catenary wire system near

1710-462: A second parallel overhead line for the return, and two trolley poles , one contacting each overhead wire. ( Pantographs are generally incompatible with parallel overhead lines.) The circuit is completed by using both wires. Parallel overhead wires are also used on the rare railways with three-phase AC railway electrification . In the Soviet Union the following types of wires/cables were used. For

1824-467: A short section of line that belongs to neither grid. Some systems increase the level of safety by the midpoint of the neutral section being earthed. The presence of the earthed section in the middle is to ensure that should the transducer controlled apparatus fail, and the driver also fail to shut off power, the energy in the arc struck by the pantograph as it passes to the neutral section is conducted to earth, operating substation circuit breakers, rather than

1938-695: A similar technology, Pirotsky put into service the first public electric tramway in St. Petersburg, which operated only during September 1880. The second demonstration tramway was presented by Siemens & Halske at the 1879 Berlin Industrial Exposition. The first public electric tramway used for permanent service was the Gross-Lichterfelde tramway in Lichterfelde near Berlin in Germany, which opened in 1881. It

2052-530: A simpler alternative for moveable overhead power rails. Electric trains coast across the gaps. To prevent arcing, power must be switched off before reaching the gap and usually the pantograph would be lowered. Given limited clearance such as in tunnels , the overhead wire may be replaced by a rigid overhead rail. An early example was in the tunnels of the Baltimore Belt Line , where a Π section bar (fabricated from three strips of iron and mounted on wood)

2166-471: A tilted position into the horizontal position, connecting the conductor rails at the transition end section and the bridge together to supply power. Short overhead conductor rails are installed at tram stops as for the Combino Supra . Trams draw their power from a single overhead wire at about 500 to 750  V DC. Trolleybuses draw from two overhead wires at a similar voltage, and at least one of

2280-639: A tramway. The tramway operated on 600–700 V DC and the railway on 15 kV AC . In the Swiss village of Oberentfelden , the Menziken–Aarau–Schöftland line operating at 750 V DC crosses the SBB line at 15 kV AC; there used to be a similar crossing between the two lines at Suhr but this was replaced by an underpass in 2010. Some crossings between tramway/light rail and railways are extant in Germany. In Zürich , Switzerland, VBZ trolleybus line 32 has

2394-911: A well-known tourist attraction . A single cable line also survives in Wellington (rebuilt in 1979 as a funicular but still called the " Wellington Cable Car "). Another system, with two separate cable lines and a shared power station in the middle, operates from the Welsh town of Llandudno up to the top of the Great Orme hill in North Wales , UK. Hastings and some other tramways, for example Stockholms Spårvägar in Sweden and some lines in Karachi , used petrol trams. Galveston Island Trolley in Texas operated diesel trams due to

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2508-422: Is briefly in contact with both wires). In normal service, the two sections are electrically connected; depending on the system this might be an isolator, fixed contact or a Booster Transformer. The isolator allows the current to the section to be interrupted for maintenance. On overhead wires designed for trolley poles, this is done by having a neutral section between the wires, requiring an insulator. The driver of

2622-422: Is in use, standard sizes for contact wire are 100 and 150 mm . The catenary wire is made of copper or copper alloys of 70, 120 or 150 mm . The smaller cross sections are made of 19 strands, whereas the bigger has 37 strands. Two standard configurations for main lines consist of two contact wires of 100 mm and one or two catenary wires of 120 mm , totaling 320 or 440 mm . Only one contact wire

2736-415: Is insufficient to guard against this as the pantograph briefly connects both sections. In countries such as France, South Africa, Australia and the United Kingdom, a pair of permanent magnets beside the rails at either side of the neutral section operate a bogie-mounted transducer on the train which causes a large electrical circuit-breaker to open and close when the locomotive or the pantograph vehicle of

2850-447: Is often used for side tracks. In the UK and EU countries , the contact wire is typically made from copper alloyed with other metals. Sizes include cross-sectional areas of 80, 100, 107, 120, and 150 mm . Common materials include normal and high strength copper, copper-silver, copper-cadmium, copper-magnesium, and copper-tin, with each being identifiable by distinct identification grooves along

2964-421: Is set up so that the vehicle's pantograph is in continuous contact with one wire or the other. For bow collectors and pantographs, this is done by having two contact wires run side by side over the length between 2 or 4 wire supports. A new one drops down and the old one rises up, allowing the pantograph to smoothly transfer from one to the other. The two wires do not touch (although the bow collector or pantograph

3078-622: Is still in operation in modernised form. The earliest tram system in Canada was built by John Joseph Wright , brother of the famous mining entrepreneur Whitaker Wright , in Toronto in 1883, introducing electric trams in 1892. In the US, multiple experimental electric trams were exhibited at the 1884 World Cotton Centennial World's Fair in New Orleans, Louisiana , but they were not deemed good enough to replace

3192-729: Is the sole survivor of the fleet). In Italy, in Trieste , the Trieste–Opicina tramway was opened in 1902, with the steepest section of the route being negotiated with the help of a funicular and its cables. Cable cars suffered from high infrastructure costs, since an expensive system of cables , pulleys , stationary engines and lengthy underground vault structures beneath the rails had to be provided. They also required physical strength and skill to operate, and alert operators to avoid obstructions and other cable cars. The cable had to be disconnected ("dropped") at designated locations to allow

3306-981: Is used only on the Gornergrat Railway and Jungfrau Railway in Switzerland, the Petit train de la Rhune in France, and the Corcovado Rack Railway in Brazil. Until 1976, it was widely used in Italy. On these railways, the two conductors are used for two different phases of the three-phase AC, while the rail was used for the third phase. The neutral was not used. Some three-phase AC railways used three overhead wires. These were an experimental railway line of Siemens in Berlin-Lichtenberg in 1898 (length 1.8 kilometres (1.1 mi)),

3420-688: The Bleecker Street Line until its closure in 1917. Pittsburgh, Pennsylvania , had its Sarah Street line drawn by horses until 1923. The last regular mule-drawn cars in the US ran in Sulphur Rock, Arkansas , until 1926 and were commemorated by a U.S. postage stamp issued in 1983. The last mule tram service in Mexico City ended in 1932, and a mule tram in Celaya, Mexico , survived until 1954. The last horse-drawn tram to be withdrawn from public service in

3534-541: The El Sereno community of Eastside Los Angeles . The route began as a horsecar line. In 1894, the Pasadena & Los Angeles Electric Railway purchased, re-gauged , electrified, and double-tracked a section of the line for streetcar use. Service began on May 6, 1895. Pacific Electric acquired the route in 1898, and the line was again rebuilt to standard gauge . Upon opening on November 11, 1902, service ran between

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3648-879: The Lamm fireless engines then propelling the St. Charles Avenue Streetcar in that city. The first commercial installation of an electric streetcar in the United States was built in 1884 in Cleveland, Ohio , and operated for a period of one year by the East Cleveland Street Railway Company. The first city-wide electric streetcar system was implemented in 1886 in Montgomery, Alabama , by the Capital City Street Railway Company, and ran for 50 years. In 1888,

3762-692: The Richmond Union Passenger Railway began to operate trams in Richmond, Virginia , that Frank J. Sprague had built. Sprague later developed multiple unit control, first demonstrated in Chicago in 1897, allowing multiple cars to be coupled together and operated by a single motorman. This gave rise to the modern subway train. Following the improvement of an overhead "trolley" system on streetcars for collecting electricity from overhead wires by Sprague, electric tram systems were rapidly adopted across

3876-785: The West Midlands Metro in Birmingham , England adopted battery-powered trams on sections through the city centre close to Grade I listed Birmingham Town Hall . Paris and Berne (Switzerland) operated trams that were powered by compressed air using the Mekarski system . Trials on street tramways in Britain, including by the North Metropolitan Tramway Company between Kings Cross and Holloway, London (1883), achieved acceptable results but were found not to be economic because of

3990-463: The tram or trolleybus must temporarily reduce the power draw before the trolley pole passes through, to prevent arc damage to the insulator. Pantograph-equipped locomotives must not run through a section break when one side is de-energized. The locomotive would become trapped, but as it passes the section break the pantograph briefly shorts the two catenary lines. If the opposite line is de-energized, this voltage transient may trip supply breakers. If

4104-492: The 1500 V DC overhead of the railway and the 650 V DC of the trams, called a Tram Square. Several such crossings have been grade separated in recent years as part of the Level Crossing Removal Project . Athens has two crossings of tram and trolleybus wires, at Vas. Amalias Avenue and Vas. Olgas Avenue, and at Ardittou Street and Athanasiou Diakou Street. They use the above-mentioned solution. In Rome , at

4218-1202: The 1850s, after which the "animal railway" became an increasingly common feature in the larger towns. The first permanent tram line in continental Europe was opened in Paris in 1855 by Alphonse Loubat who had previously worked on American streetcar lines. The tram was developed in numerous cities of Europe (some of the most extensive systems were found in Berlin, Budapest , Birmingham , Saint Petersburg , Lisbon , London , Manchester , Paris , Kyiv ). The first tram in South America opened in 1858 in Santiago, Chile . The first trams in Australia opened in 1860 in Sydney . Africa's first tram service started in Alexandria on 8 January 1863. The first trams in Asia opened in 1869 in Batavia (Jakarta), Netherlands East Indies (Indonesia) . Limitations of horsecars included

4332-692: The 1894-built horse tram at Victor Harbor in South Australia . New horse-drawn systems have been established at the Hokkaidō Museum in Japan and also in Disneyland . A horse-tram route in Polish gmina Mrozy , first built in 1902, was reopened in 2012. The first mechanical trams were powered by steam . Generally, there were two types of steam tram. The first and most common had a small steam locomotive (called

4446-420: The 1980s. The history of passenger trams, streetcars and trolley systems, began in the early nineteenth century. It can be divided into several distinct periods defined by the principal means of power used. Precursors to the tramway included the wooden or stone wagonways that were used in central Europe to transport mine carts with unflanged wheels since the 1500s, and the paved limestone trackways designed by

4560-475: The Australian state of Queensland between 1909 and 1939. Stockholm , Sweden, had a steam tram line at the island of Södermalm between 1887 and 1901. Tram engines usually had modifications to make them suitable for street running in residential areas. The wheels, and other moving parts of the machinery, were usually enclosed for safety reasons and to make the engines quieter. Measures were often taken to prevent

4674-457: The British newspaper Newcastle Daily Chronicle reported that, "A large number of London's discarded horse tramcars have been sent to Lincolnshire where they are used as sleeping rooms for potato pickers ". Horses continued to be used for light shunting well into the 20th century, and many large metropolitan lines lasted into the early 20th century. New York City had a regular horsecar service on

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4788-744: The Entertainment Centre, and work is progressing on further extensions. Sydney re-introduced trams (or light rail) on 31 August 1997. A completely new system, known as G:link , was introduced on the Gold Coast, Queensland , on 20 July 2014. The Newcastle Light Rail opened in February 2019, while the Canberra light rail opened on 20 April 2019. This is the first time that there have been trams in Canberra, even though Walter Burley Griffin 's 1914–1920 plans for

4902-517: The Hell's Gate Bridge boundary between Amtrak and Metro North 's electrifications) that would never be in-phase. Since a dead section is always dead, no special signal aspect was developed to warn drivers of its presence, and a metal sign with "DS" in drilled-hole letters was hung from the catenary supports. Occasionally gaps may be present in the overhead lines, when switching from one voltage to another or to provide clearance for ships at moveable bridges, as

5016-568: The Irish coach builder John Stephenson , in New York City which began service in the year 1832. The New York and Harlem Railroad's Fourth Avenue Line ran along the Bowery and Fourth Avenue in New York City. It was followed in 1835 by the New Orleans and Carrollton Railroad in New Orleans, Louisiana , which still operates as the St. Charles Streetcar Line . Other American cities did not follow until

5130-534: The Netherlands. The first trams in Bendigo, Australia, in 1892, were battery-powered, but within as little as three months they were replaced with horse-drawn trams. In New York City some minor lines also used storage batteries. Then, more recently during the 1950s, a longer battery-operated tramway line ran from Milan to Bergamo . In China there is a Nanjing battery Tram line and has been running since 2014. In 2019,

5244-755: The North Sydney line from 1886 to 1900, and the King Street line from 1892 to 1905. In Dresden , Germany, in 1901 an elevated suspended cable car following the Eugen Langen one-railed floating tram system started operating. Cable cars operated on Highgate Hill in North London and Kennington to Brixton Hill in South London. They also worked around "Upper Douglas" in the Isle of Man from 1897 to 1929 (cable car 72/73

5358-584: The Raymond Hotel and the junction with the Alhambra Line . Negotiations to cross the existing roads — the Santa Fe Railway , Terminal Railway, and California Cycleway  — led Pacific Electric to build a bridge over the right of ways shortly after their service commenced. In 1908, double tracking was completed throughout. Between 1912 and 1914, the inbound terminus was moved to Ceres and Central in

5472-720: The Romans for heavy horse and ox-drawn transportation. By the 1700s, paved plateways with cast iron rails were introduced in England for transporting coal, stone or iron ore from the mines to the urban factories and docks. The world's first passenger train or tram was the Swansea and Mumbles Railway , in Wales , UK. The British Parliament passed the Mumbles Railway Act in 1804, and horse-drawn service started in 1807. The service closed in 1827, but

5586-413: The Second Street Cable Railroad, which operated from 1885 to 1889, and the Temple Street Cable Railway, which operated from 1886 to 1898. From 1885 to 1940, the city of Melbourne , Victoria, Australia operated one of the largest cable systems in the world, at its peak running 592 trams on 75 kilometres (47 mi) of track. There were also two isolated cable lines in Sydney , New South Wales, Australia;

5700-562: The UK at Lytham St Annes , Trafford Park , Manchester (1897–1908) and Neath , Wales (1896–1920). Comparatively little has been published about gas trams. However, research on the subject was carried out for an article in the October 2011 edition of "The Times", the historical journal of the Australian Association of Timetable Collectors, later renamed the Australian Timetable Association. The world's first electric tram line operated in Sestroretsk near Saint Petersburg invented and tested by inventor Fyodor Pirotsky in 1875. Later, using

5814-410: The UK took passengers from Fintona railway station to Fintona Junction one mile away on the main Omagh to Enniskillen railway in Northern Ireland. The tram made its last journey on 30 September 1957 when the Omagh to Enniskillen line closed. The "van" is preserved at the Ulster Transport Museum . Horse-drawn trams still operate on the 1876-built Douglas Bay Horse Tramway on the Isle of Man , and at

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5928-426: The Watts Line virtually ended on October 22, 1950, with the franchise run discontinued on December 28. Service ended on September 30, 1951. This tram-, streetcar-, or light rail-related article is a stub . You can help Misplaced Pages by expanding it . This article about transportation in California is a stub . You can help Misplaced Pages by expanding it . Streetcar A tram (also known as

6042-508: The advantages over earlier forms of transit was the low rolling resistance of metal wheels on steel rails, allowing the trams to haul a greater load for a given effort. Another factor which contributed to the rise of trams was the high total cost of ownership of horses. Electric trams largely replaced animal power in the late 19th and early 20th centuries. Improvements in other vehicles such as buses led to decline of trams in early to mid 20th century. However, trams have seen resurgence since

6156-493: The arc either bridging the insulators into a section made dead for maintenance, a section fed from a different phase, or setting up a Backdoor connection between different parts of the country's national grid. On the Pennsylvania Railroad , phase breaks were indicated by a position light signal face with all eight radial positions with lenses and no center light. When the phase break was active (the catenary sections out of phase), all lights were lit. The position light signal aspect

6270-460: The busiest tram line in Europe, with a tram running once per minute at rush hour. Bucharest and Belgrade ran a regular service from 1894. Ljubljana introduced its tram system in 1901 – it closed in 1958. Oslo had the first tramway in Scandinavia , starting operation on 2 March 1894. The first electric tramway in Australia was a Sprague system demonstrated at the 1888 Melbourne Centennial Exhibition in Melbourne ; afterwards, this

6384-439: The capital then in the planning stage did propose a Canberra tram system. In Japan, the Kyoto Electric railroad was the first tram system, starting operation in 1895. By 1932, the network had grown to 82 railway companies in 65 cities, with a total network length of 1,479 km (919 mi). By the 1960s the tram had generally died out in Japan. Two rare but significant alternatives were conduit current collection , which

6498-458: The car up the hill at a steady pace, unlike a low-powered steam or horse-drawn car. Cable cars do have wheel brakes and track brakes , but the cable also helps restrain the car to going downhill at a constant speed. Performance in steep terrain partially explains the survival of cable cars in San Francisco. The San Francisco cable cars , though significantly reduced in number, continue to provide regular transportation service, in addition to being

6612-402: The cars to coast by inertia, for example when crossing another cable line. The cable then had to be "picked up" to resume progress, the whole operation requiring precise timing to avoid damage to the cable and the grip mechanism. Breaks and frays in the cable, which occurred frequently, required the complete cessation of services over a cable route while the cable was repaired. Due to overall wear,

6726-409: The city's hurricane-prone location, which would have resulted in frequent damage to an electrical supply system. Although Portland, Victoria promotes its tourist tram as being a cable car it actually operates using a diesel motor. The tram, which runs on a circular route around the town of Portland, uses dummies and salons formerly used on the Melbourne cable tramway system and since restored. In

6840-549: The classic tramway built in the early 20th century with the tram system operating in mixed traffic, and the later type which is most often associated with the tram system having its own right of way. Tram systems that have their own right of way are often called light rail but this does not always hold true. Though these two systems differ in their operation, their equipment is much the same. Overhead line An overhead line consists of one or more wires (or rails , particularly in tunnels) situated over rail tracks , raised to

6954-416: The combined coal consumption of the stationary compressor and the onboard steam boiler. The Trieste–Opicina tramway in Trieste operates a hybrid funicular tramway system. Conventional electric trams are operated in street running and on reserved track for most of their route. However, on one steep segment of track, they are assisted by cable tractors, which push the trams uphill and act as brakes for

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7068-612: The contact wire, cold drawn solid copper was used to ensure good conductivity . The wire is not round but has grooves at the sides to allow the hangers to attach to it. Sizes were (in cross-sectional area) 85, 100, or 150 mm . To make the wire stronger, 0.04% tin might be added. The wire must resist the heat generated by arcing and thus such wires should never be spliced by thermal means. The messenger (or catenary) wire needs to be both strong and have good conductivity. They used multi-strand wires (or cables) with 19 strands in each cable (or wire). Copper, aluminum, and/or steel were used for

7182-476: The controller into neutral and coast through. Trolleybus drivers had to either lift off the accelerator or switch to auxiliary power. In Melbourne , Victoria, tram drivers put the controller into neutral and coast through section insulators, indicated by insulator markings between the rails. Melbourne has several remaining level crossings between electrified suburban railways and tram lines. They have mechanical switching arrangements (changeover switch) to switch

7296-526: The crossing between Viale Regina Margherita and Via Nomentana, tram and trolleybus lines cross: tram on Viale Regina Margherita and trolleybus on Via Nomentana. The crossing is orthogonal, therefore the typical arrangement was not available. In Milan , most tram lines cross its circular trolleybus line once or twice. Trolleybus and tram wires run parallel in streets such as viale Stelvio, viale Umbria and viale Tibaldi. Some railways used two or three overhead lines, usually to carry three-phase current. This

7410-430: The downhill run. For safety, the cable tractors are always deployed on the downhill side of the tram vehicle. Similar systems were used elsewhere in the past, notably on the Queen Anne Counterbalance in Seattle and the Darling Street wharf line in Sydney. In the mid-20th century many tram systems were disbanded, replaced by buses, trolleybuses , automobiles or rapid transit . The General Motors streetcar conspiracy

7524-446: The engines from emitting visible smoke or steam. Usually the engines used coke rather than coal as fuel to avoid emitting smoke; condensers or superheating were used to avoid emitting visible steam. A major drawback of this style of tram was the limited space for the engine, so that these trams were usually underpowered. Steam trams faded out around the 1890s to 1900s, being replaced by electric trams. Another motive system for trams

7638-429: The entire length of cable (typically several kilometres) had to be replaced on a regular schedule. After the development of reliable electrically powered trams, the costly high-maintenance cable car systems were rapidly replaced in most locations. Cable cars remained especially effective in hilly cities, since their nondriven wheels did not lose traction as they climbed or descended a steep hill. The moving cable pulled

7752-439: The fact that any given animal could only work so many hours on a given day, had to be housed, groomed, fed and cared for day in and day out, and produced prodigious amounts of manure, which the streetcar company was charged with storing and then disposing. Since a typical horse pulled a streetcar for about a dozen miles a day and worked for four or five hours, many systems needed ten or more horses in stable for each horsecar. In 1905

7866-444: The late 19th and early 20th centuries a number of systems in various parts of the world employed trams powered by gas, naphtha gas or coal gas in particular. Gas trams are known to have operated between Alphington and Clifton Hill in the northern suburbs of Melbourne , Australia (1886–1888); in Berlin and Dresden , Germany; in Estonia (1921–1951); between Jelenia Góra , Cieplice , and Sobieszów in Poland (from 1897); and in

7980-402: The late 19th and early 20th centuries. There was one particular hazard associated with trams powered from a trolley pole off an overhead line on the early electrified systems. Since the tram relies on contact with the rails for the current return path, a problem arises if the tram is derailed or (more usually) if it halts on a section of track that has been heavily sanded by a previous tram, and

8094-451: The line is under maintenance, an injury may occur as the catenary is suddenly energized. Even if the catenary is properly grounded to protect the personnel, the arc generated across the pantograph can damage the pantograph, the catenary insulator or both. Sometimes on a larger electrified railway, tramway or trolleybus system, it is necessary to power different areas of track from different power grids, without guaranteeing synchronisation of

8208-478: The military railway between Marienfelde and Zossen between 1901 and 1904 (length 23.4 kilometres (14.5 mi)) and an 800-metre (2,600 ft)-long section of a coal railway near Cologne between 1940 and 1949. On DC systems, bipolar overhead lines were sometimes used to avoid galvanic corrosion of metallic parts near the railway, such as on the Chemin de fer de la Mure . All systems with multiple overhead lines have

8322-409: The natural path of a wire strung between two points, a catenary curve , thus the use of "catenary" to describe this wire or sometimes the whole system. This wire is attached to the contact wire at regular intervals by vertical wires known as "droppers" or "drop wires". It is supported regularly at structures, by a pulley , link or clamp . The whole system is then subjected to mechanical tension . As

8436-528: The necessity of overhead wire and a trolley pole for street cars and railways. While at the University of Denver he conducted experiments which established that multiple unit powered cars were a better way to operate trains and trolleys. Electric tramways spread to many European cities in the 1890s, such as: Sarajevo built a citywide system of electric trams in 1895. Budapest established its tramway system in 1887, and its ring line has grown to be

8550-523: The oldest operating electric tramway in the world. Also in 1883, Mödling and Hinterbrühl Tram was opened near Vienna in Austria. It was the first tram in the world in regular service that was run with electricity served by an overhead line with pantograph current collectors . The Blackpool Tramway was opened in Blackpool, UK on 29 September 1885 using conduit collection along Blackpool Promenade. This system

8664-402: The overhead conductor rail that runs across the entire span of the swing bridge. The gap is required for the swing bridge to be opened and closed. To connect the conductor rails together when the bridge is closed, there is another conductor rail section called "rotary overlap" that is equipped with a motor. When the bridge is fully closed, the motor of the rotary overlap is operated to turn it from

8778-480: The overhead line is limited due to the change in the height of the weights as the overhead line expands and contracts with temperature changes. This movement is proportional to the distance between anchors. Tension length has a maximum. For most 25 kV OHL equipment in the UK, the maximum tension length is 1,970 m (6,460 ft). An additional issue with AT equipment is that, if balance weights are attached to both ends,

8892-455: The pantograph as the train travels around the curve. The movement of the contact wire across the head of the pantograph is called the "sweep". The zigzagging of the overhead line is not required for trolley poles. For tramways , a contact wire without a messenger wire is used. Depot areas tend to have only a single wire and are known as "simple equipment" or "trolley wire". When overhead line systems were first conceived, good current collection

9006-457: The pantograph causes mechanical oscillations in the wire. The waves must travel faster than the train to avoid producing standing waves , which could break the wire. Tensioning the line makes waves travel faster, and also reduces sag from gravity. For medium and high speeds, the wires are generally tensioned by weights or occasionally by hydraulic tensioners. Either method is known as "auto-tensioning" (AT) or "constant tension" and ensures that

9120-411: The pantograph moves along under the contact wire, the carbon insert on top of the pantograph becomes worn with time. On straight track, the contact wire is zigzagged slightly to the left and right of the centre from each support to the next so that the insert wears evenly, thus preventing any notches. On curves, the "straight" wire between the supports causes the contact point to cross over the surface of

9234-424: The phases. Long lines may be connected to the country's national grid at various points and different phases. (Sometimes the sections are powered with different voltages or frequencies.) The grids may be synchronised on a normal basis, but events may interrupt synchronisation. This is not a problem for DC systems. AC systems have a particular safety implication in that the railway electrification system would act as

9348-617: The poor paving of the streets in American cities which made them unsuitable for horsebuses , which were then common on the well-paved streets of European cities. Running the horsecars on rails allowed for a much smoother ride. There are records of a street railway running in Baltimore as early as 1828, however the first authenticated streetcar in America, was the New York and Harlem Railroad developed by

9462-519: The reactive upward pull of the tensioned wires lift the pulley so its teeth are well clear of a stop on the mast. The pulley can turn freely while the weights move up or down as the wires contract or expand. If tension is lost the pulley falls back toward the mast, and one of its teeth jams against the stop. This stops further rotation, limits the damage, and keeps the undamaged part of the wire intact until it can be repaired. Other systems use various braking mechanisms, usually with multiple smaller pulleys in

9576-679: The rear of Southern Pacific's Arcade Depot . Starting August 1915, local services on the line were assumed by interurban runs. Independent service was reestablished in December 1916, instead terminating at the elevated concourse at the Pacific Electric Building. Alhambra–San Gabriel Line cars absorbed local services again between November 1918 and February 1920. The Sierra Vista Line operated exclusively in Pacific Electric's Northern District until 1938. Beginning March 20 of that year,

9690-641: The service was multiplexed with the Southern District Watts Line . The Aliso Street bridge opened in 1943, eliminating grade crossings with the Union Pacific and Santa Fe Railroad . From 1943 to 1948, local service was extended over the Short Line past Sierra Vista as far as Pasadena. Passenger volumes during World War II additionally necessitated cars terminating downtown to run via a loop on San Pedro, 6th, and Main streets. Through-routing with

9804-420: The stiffness of the spring for ease of maintenance. For low speeds and in tunnels where temperatures are constant, fixed termination (FT) equipment may be used, with the wires terminated directly on structures at each end of the overhead line. The tension is generally about 10 kN (2,200 lbf). This type of equipment sags in hot conditions and is taut in cold conditions. With AT, the continuous length of

9918-488: The strands. All 19 strands could be made of the same metal or a mix of metals based on the required properties. For example, steel wires were used for strength, while aluminium or copper wires were used for conductivity. Another type looked like it had all copper wires but inside each wire was a steel core for strength. The steel strands were galvanized but for better corrosion protection they could be coated with an anti-corrosion substance. In Slovenia , where 3 kV system

10032-529: The suburban tramway lines around Milan and Padua ; the last Gamba de Legn ("Peg-Leg") tramway ran on the Milan- Magenta -Castano Primo route in late 1957. The other style of steam tram had the steam engine in the body of the tram, referred to as a tram engine (UK) or steam dummy (US). The most notable system to adopt such trams was in Paris. French-designed steam trams also operated in Rockhampton , in

10146-514: The tension is virtually independent of temperature. Tensions are typically between 9 and 20  kN (2,000 and 4,500  lbf ) per wire. Where weights are used, they slide up and down on a rod or tube attached to the mast, to prevent them from swaying. Recently, spring tensioners have started to be used. These devices contain a torsional spring with a cam arrangement to ensure a constant applied tension (instead of varying proportionally with extension). Some devices also include mechanisms for adjusting

10260-545: The tracks. Siemens later designed his own version of overhead current collection, called the bow collector . One of the first systems to use it was in Thorold, Ontario , opened in 1887, and it was considered quite successful. While this line proved quite versatile as one of the earliest fully functional electric streetcar installations, it required horse-drawn support while climbing the Niagara Escarpment and for two months of

10374-494: The train or tram and back to the feeder station through the steel wheels on one or both running rails. Non-electric locomotives (such as diesels ) may pass along these tracks without affecting the overhead line, although there may be difficulties with overhead clearance . Alternative electrical power transmission schemes for trains include third rail , ground-level power supply , batteries and electromagnetic induction . Vehicles like buses that have rubber tyres cannot provide

10488-416: The tram and completing the earth return circuit with their body could receive a serious electric shock. If "grounded", the driver was required to jump off the tram (avoiding simultaneous contact with the tram and the ground) and pull down the trolley pole, before allowing passengers off the tram. Unless derailed, the tram could usually be recovered by running water down the running rails from a point higher than

10602-460: The tram loses electrical contact with the rails. In this event, the underframe of the tram, by virtue of a circuit path through ancillary loads (such as interior lighting), is live at the full supply voltage, typically 600 volts DC. In British terminology, such a tram was said to be 'grounded'—not to be confused with the US English use of the term, which means the exact opposite. Any person stepping off

10716-465: The tram wire. The tram's pantograph bridges the gap between the different conductors, providing it with a continuous pickup. Where the tram wire crosses, the trolleybus wires are protected by an inverted trough of insulating material extending 20 or 30 mm (0.79 or 1.18 in) below. Until 1946, a level crossing in Stockholm , Sweden connected the railway south of Stockholm Central Station and

10830-427: The tram, the water providing a conducting bridge between the tram and the rails. With improved technology, this ceased to be an problem. In the 2000s, several companies introduced catenary-free designs: Alstom's Citadis line uses a third rail, Bombardier's PRIMOVE LRV is charged by contactless induction plates embedded in the trackway and CAF URBOS tram uses ultracaps technology As early as 1834, Thomas Davenport ,

10944-444: The trolleybus wires must be insulated from tram wires. This is usually done by the trolleybus wires running continuously through the crossing, with the tram conductors a few centimetres lower. Close to the junction on each side, the tram wire turns into a solid bar running parallel to the trolleybus wires for about half a metre. Another bar similarly angled at its ends is hung between the trolleybus wires, electrically connected above to

11058-406: The upper lobe of the contact wire. These grooves vary in number and location on the arc of the upper section. Copper is chosen for its excellent conductivity, with other metals added to increase tensile strength. The choice of material is chosen based on the needs of the particular system, balancing the need for conductivity and tensile strength. Catenary wires are kept in mechanical tension because

11172-496: The whole tension length is free to move along the track. To avoid this a midpoint anchor (MPA), close to the centre of the tension length, restricts movement of the messenger/catenary wire by anchoring it; the contact wire and its suspension hangers can move only within the constraints of the MPA. MPAs are sometimes fixed to low bridges, or otherwise anchored to vertical catenary poles or portal catenary supports. A tension length can be seen as

11286-804: The wider term light rail , which also includes systems separated from other traffic. Tram vehicles are usually lighter and shorter than main line and rapid transit trains. Most trams use electrical power, usually fed by a pantograph sliding on an overhead line ; older systems may use a trolley pole or a bow collector . In some cases, a contact shoe on a third rail is used. If necessary, they may have dual power systems—electricity in city streets and diesel in more rural environments. Occasionally, trams also carry freight . Some trams, known as tram-trains , may have segments that run on mainline railway tracks, similar to interurban systems. The differences between these modes of rail transport are often indistinct, and systems may combine multiple features. One of

11400-409: The winter when hydroelectricity was not available. It continued in service in its original form into the 1950s. Sidney Howe Short designed and produced the first electric motor that operated a streetcar without gears. The motor had its armature direct-connected to the streetcar 's axle for the driving force. Short pioneered "use of a conduit system of concealed feed" thereby eliminating

11514-524: The world's first hydrogen fuel cell vehicle tramcar at an assembly facility in Qingdao . The chief engineer of the CSR subsidiary CSR Sifang Co Ltd. , Liang Jianying, said that the company is studying how to reduce the running costs of the tram. Trams have been used for two main purposes: for carrying passengers and for carrying cargo. There are several types of passenger tram: There are two main types of tramways,

11628-401: The world. Earlier electric trains proved difficult or unreliable and experienced limited success until the second half of the 1880s, when new types of current collectors were developed. Siemens' line, for example, provided power through a live rail and a return rail, like a model train , limiting the voltage that could be used, and delivering electric shocks to people and animals crossing

11742-665: Was a case study of the decline of trams in the United States. In the 21st century, trams have been re-introduced in cities where they had been closed down for decades (such as Tramlink in London), or kept in heritage use (such as Spårväg City in Stockholm). Most trams made since the 1990s (such as the Bombardier Flexity series and Alstom Citadis ) are articulated low-floor trams with features such as regenerative braking . In March 2015, China South Rail Corporation (CSR) demonstrated

11856-486: Was built by Werner von Siemens who contacted Pirotsky. This was the world's first commercially successful electric tram. It drew current from the rails at first, with overhead wire being installed in 1883. In Britain, Volk's Electric Railway was opened in 1883 in Brighton. This two kilometer line along the seafront, re-gauged to 2 ft  8 + 1 ⁄ 2  in ( 825 mm ) in 1884, remains in service as

11970-482: Was installed as a commercial venture operating between the outer Melbourne suburb of Box Hill and the then tourist-oriented country town Doncaster from 1889 to 1896. Electric systems were also built in Adelaide , Ballarat , Bendigo , Brisbane , Fremantle , Geelong , Hobart , Kalgoorlie , Launceston , Leonora , Newcastle , Perth , and Sydney . By the 1970s, the only full tramway system remaining in Australia

12084-665: Was originally devised by the Pennsylvania Railroad and was continued by Amtrak and adopted by Metro North . Metal signs were hung from the catenary supports with the letters "PB" created by a pattern of drilled holes. A special category of phase break was developed in America, primarily by the Pennsylvania Railroad. Since its traction power network was centrally supplied and only segmented by abnormal conditions, normal phase breaks were generally not active. Phase breaks that were always activated were known as "Dead Sections": they were often used to separate power systems (for example,

12198-429: Was possible only at low speeds, using a single wire. To enable higher speeds, two additional types of equipment were developed: Earlier dropper wires provided physical support of the contact wire without joining the catenary and contact wires electrically. Modern systems use current-carrying droppers, eliminating the need for separate wires. The present transmission system originated about 100 years ago. A simpler system

12312-476: Was proposed in the 1970s by the Pirelli Construction Company, consisting of a single wire embedded at each support for 2.5 metres (8 ft 2 in) of its length in a clipped, extruded aluminum beam with the wire contact face exposed. A somewhat higher tension than used before clipping the beam yielded a deflected profile for the wire that could be easily handled at 400 km/h (250 mph) by

12426-548: Was restarted in 1860, again using horses. It was worked by steam from 1877, and then, from 1929, by very large (106-seat) electric tramcars, until closure in 1960. The Swansea and Mumbles Railway was something of a one-off however, and no street tramway appeared in Britain until 1860 when one was built in Birkenhead by the American George Francis Train . Street railways developed in America before Europe, due to

12540-616: Was tested in San Francisco , in 1873. Part of its success is attributed to the development of an effective and reliable cable grip mechanism, to grab and release the moving cable without damage. The second city to operate cable trams was Dunedin , from 1881 to 1957. The most extensive cable system in the US was built in Chicago in stages between 1859 and 1892. New York City developed multiple cable car lines, that operated from 1883 to 1909. Los Angeles also had several cable car lines, including

12654-616: Was the Melbourne tram system. However, there were also a few single lines remaining elsewhere: the Glenelg tram line , connecting Adelaide to the beachside suburb of Glenelg , and tourist trams in the Victorian Goldfields cities of Bendigo and Ballarat. In recent years the Melbourne system, generally recognised as the largest urban tram network in the world, has been considerably modernised and expanded. The Adelaide line has been extended to

12768-411: Was the cable car, which was pulled along a fixed track by a moving steel cable, the cable usually running in a slot below the street level. The power to move the cable was normally provided at a "powerhouse" site a distance away from the actual vehicle. The London and Blackwall Railway , which opened for passengers in east London, England, in 1840 used such a system. The first practical cable car line

12882-461: Was used, with the brass contact running inside the groove. When the overhead line was raised in the Simplon Tunnel to accommodate taller rolling stock, a rail was used. A rigid overhead rail may also be used in places where tensioning the wires is impractical, for example on moveable bridges . In modern uses, it is very common for underground sections of trams, metros, and mainline railways to use

12996-806: Was widely used in London, Washington, D.C., and New York City, and the surface contact collection method, used in Wolverhampton (the Lorain system), Torquay and Hastings in the UK (the Dolter stud system), and in Bordeaux , France (the ground-level power supply system). The convenience and economy of electricity resulted in its rapid adoption once the technical problems of production and transmission of electricity were solved. Electric trams largely replaced animal power and other forms of motive power including cable and steam, in

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