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Twin-unit
A twin unit, twinset, or double unit is a set of two railroad cars or locomotives which are permanently coupled and treated as if they were a single unit. A twinset of cars or coaches can also be called a twin car. In US passenger railroad parlance, twin units are also known as married pairs. On passenger railroads, light rail, and monorail services, married pairs may have machinery necessary for full operation of the cars split between them. Items that are typically shared include transformers, motor controllers, dynamic braking grids, cabs, current collectors, batteries, and air compressors. This provides significant savings in both cost of equipment and weight, which increases performance and decreases energy consumption. The cost of operating such a pair may be slightly higher when the extra car in such a pair is not needed to meet level-of-service demands at a particular time. See also * Cow–calf * Multiple unit A multiple-unit train (or multiple unit (MU)) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trams At Cabin, Blackpool - Geograph
A tram (also known as a streetcar or trolley in Canada and the United States) is an urban rail transit in which Rolling stock, vehicles, whether individual railcars or multiple-unit trains, run on tramway tracks on urban public streets; some include segments on segregated Right-of-way (property access), 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 the wider term ''light rail'', which also includes systems separated from other traffic. Tram vehicles are usually lighter and shorter than Main line (railway), main line and rapid transit trains. Most trams use electrical power, usually fed by a Pantograph (transport), 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 stre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N Judah Train Crossing 10th Avenue, March 2001
N, or n, is the fourteenth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages, and others worldwide. Its name in English is ''en'' (pronounced ), plural ''ens''. History One of the most common hieroglyphs, snake, was used in Egyptian writing to stand for a sound like the English , because the Egyptian word for "snake" was ''djet''. It is speculated by some, such as archeologist Douglas Petrovich, that Semitic speakers working in Egypt adapted hieroglyphs to create the first alphabet. Some hold that they used the same snake symbol to represent N, with a great proponent of this theory being Alan Gardiner, because their word for "snake" may have begun with n (an example of a possible word being ''nahash''). However, this theory has become disputed. The name for the letter in the Phoenician, Hebrew, Aramaic, and Arabic alphabets is ''nun'', which means "fish" in some of these languages. This possibly conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railroad
Rail transport (also known as train transport) is a means of transport using wheeled vehicles running in railway track, tracks, which usually consist of two parallel steel railway track, rails. Rail transport is one of the two primary means of land transport, next to road transport. It is used for about 8% of passenger and rail freight transport, freight transport globally, thanks to its Energy efficiency in transport, energy efficiency and potentially high-speed rail, high speed.Rolling stock on rails generally encounters lower friction, frictional resistance than rubber-tyred road vehicles, allowing rail cars to be coupled into longer trains. Power is usually provided by Diesel locomotive, diesel or Electric locomotive, electric locomotives. While railway transport is capital intensity, capital-intensive and less flexible than road transport, it can carry heavy loads of passengers and cargo with greater energy efficiency and safety. Precursors of railways driven by human or an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Car
A railroad car, railcar ( American and Canadian English), railway wagon, railway carriage, railway truck, railwagon, railcarriage or railtruck (British English and UIC), also called a train car, train wagon, train carriage or train truck, is a vehicle used for the carrying of cargo or passengers on a rail transport network (a railroad/railway). Such cars, when coupled together and hauled by one or more locomotives, form a train. Alternatively, some passenger cars are self-propelled in which case they may be either single railcars or make up multiple units. The term "car" is commonly used by itself in American English when a rail context is implicit. Indian English sometimes uses "bogie" in the same manner, though the term has other meanings in other variants of English. In American English, "railcar" is a generic term for a railway vehicle; in other countries "railcar" refers specifically to a self-propelled, powered, railway vehicle. Although some cars exist for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Locomotive
A locomotive is a rail transport, rail vehicle that provides the motive power for a train. Traditionally, locomotives pulled trains from the front. However, Push–pull train, push–pull operation has become common, and in the pursuit for longer and heavier freight trains, companies are increasingly using distributed power: single or multiple locomotives placed at the front and rear and at intermediate points throughout the train under the control of the leading locomotive. Etymology The word ''locomotive'' originates from the Latin language, Latin 'from a place', Ablative case, ablative of 'place', and the Medieval Latin 'causing motion', and is a shortened form of the term ''locomotive engine'', which was first used in 1814 to distinguish between self-propelled and stationary steam engines. Classifications Prior to locomotives, the motive force for railways had been generated by various lower-technology methods such as human power, horse power, Gravity railroad, g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Rail
Light rail (or light rail transit, abbreviated to LRT) is a form of passenger urban rail transit that uses rolling stock derived from tram technology National Conference of the Transportation Research Board while also having some features from heavy rapid transit. The term was coined in 1972 in the United States as an English equivalent for the German word ''Stadtbahn'', meaning "city railway". From: 9th National Light Rail Transit Conference Different definitions exist in some countries, but in the United States, light rail operates primarily along exclusive Right_of_way#Rail_right_of_way, rights-of-way and uses either individual tramcars or multiple units coupled together, with a lower capacity and speed than a long heavy rail passenger train or rapid transit system. Narrowly defined, light rail transit uses rolling stock that is similar to that of a traditional tram, while operating at a higher capacity and speed, often on an exclusive right-of-way. In broader usage, light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monorail
A monorail is a Rail transport, railway in which the track consists of a single rail or beam. Colloquially, the term "monorail" is often used to describe any form of elevated rail or people mover. More accurately, the term refers to the style of Track (rail transport), track.The term "track" is used here for simplicity. Technically the monorail sits on or is suspended from a guideway containing a singular structure. There is an additional generally accepted rule that the support for the car must be narrower than the car. Monorail systems are most frequently implemented in large cities, airports, and theme parks. Etymology The term possibly originated in 1897 from German engineer Eugen Langen, who called an elevated railway system with wagons suspended the ''Wuppertal Schwebebahn, Eugen Langen One-railed Suspension Tramway'' (Einschieniges Hängebahnsystem Eugen Langen). Differentiation from other transport systems Monorails have found applications in airport transfers and med ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transformer
In electrical engineering, a transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple Electrical network, circuits. A varying current in any coil of the transformer produces a varying magnetic flux in the transformer's core, which induces a varying electromotive force, electromotive force (EMF) across any other coils wound around the same core. Electrical energy can be transferred between separate coils without a metallic (conductive) connection between the two circuits. Faraday's law of induction, discovered in 1831, describes the induced voltage effect in any coil due to a changing magnetic flux encircled by the coil. Transformers are used to change Alternating current, AC voltage levels, such transformers being termed step-up or step-down type to increase or decrease voltage level, respectively. Transformers can also be used to provide galvanic isolation between circuits as well as to couple stages of signa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motor Controller
A motor controller is a device or group of devices that can coordinate in a predetermined manner the performance of an electric motor. A motor controller might include a manual or automatic means for starting and stopping the motor, selecting forward or reverse rotation, selecting and regulating the speed, regulating or limiting the torque, and protecting against overloads and electrical faults. Motor controllers may use electromechanical switching, or may use power electronics devices to regulate the speed and direction of a motor. Applications Motor controllers are used with both DC motors (direct current) and AC motors (alternating current). A controller includes means to connect the motor's windings to the electrical power supply, and may also include overload, over-current, and oveheating protection and wiring (i.e. magnetic starter). A motor controller may also supervise the motor's field circuit, or detect conditions such as low supply voltage, incorrect polarity or in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamic Braking
Dynamic braking is the use of an electric traction motor as a generator when slowing a vehicle such as an electric or diesel-electric locomotive. It is termed " rheostatic" if the generated electrical power is dissipated as heat in brake grid resistors, and " regenerative" if the power is returned to the supply line. Dynamic braking reduces wear on friction-based braking components, and regeneration lowers net energy consumption. Dynamic braking may also be used on railcars with multiple units, light rail vehicles, electric trams, trolleybuses, and electric and hybrid electric automobiles. Principle of operation Converting electrical energy to the mechanical energy of a rotating shaft (electric motor) is the inverse of converting the mechanical energy of a rotating shaft to electrical energy (electric generator). Both are accomplished through the interactions of armature windings with a (relatively) moving external magnetic field, with the armature connected to an electrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Current Collector
A current collector (often called a "pickup") is a device used in trolleybuses, trams, electric locomotives and EMUs to carry electric power ( current) from overhead lines, electric third rails, or ground-level power supplies to the electrical equipment of the vehicles. Those for overhead wires are roof-mounted devices, those for rails are mounted on the bogies. Typically, electric current connectors have one or more spring-loaded arms that press a collector or contact shoe against the rail or overhead wire. As the vehicle moves, the contact shoe slides along the wire or rail to draw the electricity needed to run the vehicle's motor. The current collector arms are electrically conductive but mounted insulated on the vehicle's roof, side or base. An insulated cable connects the collector with the switch, transformer or motor. The steel rails of the tracks act as the electrical return. Pantographs and poles Electric vehicles that collect their current from an overhead ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Compressor
An air compressor is a machine that takes ambient air from the surroundings and discharges it at a higher pressure. It is an application of a gas compressor and a Pneumatics, pneumatic device that energy conversion, converts mechanical power (from an electric motor, Diesel engine, diesel or gasoline engine, etc.) into potential energy stored in compressed air, which has many uses. A common application is to compress air into a storage tank, for immediate or later use. When the delivery pressure reaches its set upper limit, the compressor is shut off, or the excess air is released through an overpressure valve. The compressed air is stored in the tank until it is needed. The pressure energy provided by the compressed air can be used for a variety of applications such as pneumatic tools as it is released. When tank pressure reaches its lower limit, the air compressor turns on again and re-pressurizes the tank. A compressor is different from a pump because it works on a gas, while pum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
