Twin-unit
   HOME
*



picture info

Twin-unit
A twin unit or twinset 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 In rail transport, a cow-calf (also cow and calf) locomotive is a set of switcher- ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Trams At Cabin, Blackpool - Geograph
A tram (called a streetcar or trolley in North America) is a rail vehicle that travels on tramway tracks on public urban streets; some include segments on segregated right-of-way. The tramlines or networks operated as public transport are called tramways or simply trams/streetcars. Many recently built tramways use the contemporary term light rail. The vehicles are called streetcars or trolleys (not to be confused with trolleybus) in North America and trams or tramcars elsewhere. The first two terms are often used interchangeably in the United States, with ''trolley'' being the preferred term in the eastern US and ''streetcar'' in the western US. ''Streetcar'' or ''tramway'' are preferred in Canada. In parts of the United States, internally powered buses made to resemble a streetcar are often referred to as "trolleys". To avoid further confusion with trolley buses, the American Public Transportation Association (APTA) refers to them as "trolley-replica buses". In the United ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Railroad
Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prepared flat surface, rail vehicles (rolling stock) are directionally guided by the tracks on which they run. Tracks usually consist of steel rails, installed on sleepers (ties) set in ballast, on which the rolling stock, usually fitted with metal wheels, moves. Other variations are also possible, such as "slab track", in which the rails are fastened to a concrete foundation resting on a prepared subsurface. Rolling stock in a rail transport system generally encounters lower frictional resistance than rubber-tyred road vehicles, so passenger and freight cars (carriages and wagons) can be coupled into longer trains. The operation is carried out by a railway company, providing transport between train stations or freight customer facili ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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 system (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 t ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Locomotive
A locomotive or engine is a rail transport vehicle that provides the Power (physics), motive power for a train. If a locomotive is capable of carrying a payload, it is usually rather referred to as a multiple unit, Motor coach (rail), motor coach, railcar or power car; the use of these self-propelled vehicles is increasingly common for passenger trains, but rare for freight (see CargoSprinter). Traditionally, locomotives pulled trains from the front. However, Push-pull train, push-pull operation has become common, where the train may have a locomotive (or locomotives) at the front, at the rear, or at each end. Most recently railroads have begun adopting DPU or distributed power. The front may have one or two locomotives followed by a mid-train locomotive that is controlled remotely from the lead unit. __TOC__ Etymology The word ''locomotive'' originates from the Latin language, Latin 'from a place', Ablative case, ablative of 'place', and the Medieval Latin 'causing mot ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Monorail
A monorail (from "mono", meaning "one", and "rail") is a railway in which the track consists of a single rail or a 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.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 be narrower than the car. Etymology The term possibly comes from 1897, from German engineer Eugen Langen, who called an elevated railway system with wagons suspended the '' Eugen Langen One-railed Suspension Tramway'' (Einschieniges Hängebahnsystem Eugen Langen). Differentiation from other transport systems Monorails have found applications in airport transfer and medium capacity metros. To differentiate monorails from other transport modes, the Monorail Society defines a monorail ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Transformer
A transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple 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 (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 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 signal-processing circuits. Since the invention of the first constant-potential transfo ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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 direct current and alternating current motors. A controller includes means to connect the motor to the electrical power supply, and may also include overload protection for the motor, and over-current protection for the motor and wiring. A motor controller may also supervise the motor's field circuit, or detect conditions such as low supply voltage, incorrect polarity or incorrect phase sequence, or h ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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]  


picture info

Current Collector
Electric current collectors are used by trolleybuses, trams, electric locomotives or EMUs to carry electrical power from overhead lines, electrical 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. Electric vehicles that collect their current from an overhead line system use different forms of one- or two-arm pantograph ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Air Compressor
An air compressor is a pneumatic device that converts power (using an electric motor, diesel or gasoline engine, etc.) into potential energy stored in pressurized air (i.e., compressed air). By one of several methods, an air compressor forces more and more air into a storage tank, increasing the pressure. When the tank's pressure reaches its engineered upper limit, the air compressor shuts off. The compressed air, then, is held in the tank until called into use. The kinetic energy provided by the compressed air can be used for a variety of applications such as pneumatic tool as it is released air and the tank depressurizes. When tank pressure reaches its lower limit, the air compressor turns on again and re-pressurizes the tank. An air compressor must be differentiated from a pump because it works for any gas/air, while pumps work on a liquid. Classification Compressors may be classified according to the pressure delivered: # Low-pressure air compressors (LPACs), which have ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Operating Cost
Operating costs or operational costs, are the expenses which are related to the operation of a business, or to the operation of a device, component, piece of equipment or facility. They are the cost of resources used by an organization just to maintain its existence. http://www.operatingcosts.com Business operating costs For a commercial enterprise, operating costs fall into three broad categories: * fixed costs, which are the same whether the operation is closed or running at 100% capacity. Fixed Costs include items such as the rent of the building. These generally have to be paid regardless of what state the business is in. It never changes * variable costs, which may increase depending on whether more production is done, and how it is done (producing 100 items of product might require 10 days of normal time or take 7 days if overtime is used. It may be more or less expensive to use overtime production depending on whether faster production means the product can be more profit ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]