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SNCF BB 13000
The BB 13000 class were electric locomotives operated by SNCF in France. They were one of four classes, together with the BB 12000, CC 14000 and CC 14100 classes, that formed an experimental group for studying the practicality of the new French electrification. 25 kV 50 Hz electrification The standard French electrification system before WWII was 1,500 V DC, beginning with locomotives such as the 2BB2 400. Post-WWII, France occupied the south-west of Germany and the Höllentalbahn. This line had been electrified with one of the first systems to use 50 Hz, the standard commercial distribution frequency, rather than the lower Hz AC frequency previously required for railway traction motors in Europe. The Höllentalbahn used a voltage of 20 kV. There was much interest post-war in using the 'industrial' frequency of 50 Hz and supplying the railways from the now established national systems of electricity generation, rather than requiring an isolat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longueau
Longueau (; pcd, Londjeu) is a Communes of France, commune in the Somme (department), Somme Departments of France, department in Hauts-de-France in northern France. Geography Longueau is situated southeast of Amiens, a suburb just by the airport, on the N29 road. Longueau station has rail connections to Amiens, Creil, Arras, Lille, Compiègne and Paris. Population Places of interest The town was once a railway centre. The reinforced concrete depot, now a registered historic monument is one of four designed by Bernard Lafaille between the two world wars. See also *Communes of the Somme department References Communes of Somme (department) {{Amiens-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French Occupation Zone
The French occupation zone in Germany (, ) was one of the Allied-occupied areas in Germany after World War II. Background In the aftermath of the Second World War, Winston Churchill, Franklin D. Roosevelt and Joseph Stalin met at the Yalta Conference to discuss Germany's post-war occupation, which included among other things coming to a final determination of the inter-zonal borders. Originally, there were to be only three zones, with the French excluded. French General Charles de Gaulle, who by this point was the leader of the Provisional Government of the French Republic, was not invited to Yalta. Deeply offended by this snub, the French leader nevertheless worked tirelessly to restore his nation's honour in the aftermath of the German occupation. Key to this was ensuring a French occupation of substantial German territories – in de Gaulle's view, only a French occupation of Germany could restore the honour of France. He therefore vehemently demanded that a zone be alloca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardan Shaft
A drive shaft, driveshaft, driving shaft, tailshaft ( Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power and torque and rotation, usually used to connect other components of a drivetrain that cannot be connected directly because of distance or the need to allow for relative movement between them. As torque carriers, drive shafts are subject to torsion and shear stress, equivalent to the difference between the input torque and the load. They must therefore be strong enough to bear the stress, while avoiding too much additional weight as that would in turn increase their inertia. To allow for variations in the alignment and distance between the driving and driven components, drive shafts frequently incorporate one or more universal joints, jaw couplings, or rag joints, and sometimes a splined joint or prismatic joint. History The term ''driveshaft'' first appeared during the mid-19th cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicon Controlled Rectifier
A silicon controlled rectifier or semiconductor controlled rectifier is a four-layer solid-state current-controlling device. The name "silicon controlled rectifier" is General Electric's trade name for a type of thyristor. The principle of four-layer p–n–p–n switching was developed by Moll, Tanenbaum, Goldey, and Holonyak of Bell Laboratories in 1956. The practical demonstration of silicon controlled switching and detailed theoretical behavior of a device in agreement with the experimental results was presented by Dr Ian M. Mackintosh of Bell Laboratories in January 1958. The SCR was developed by a team of power engineers led by Gordon Hall and commercialized by Frank W. "Bill" Gutzwiller in 1957. Some sources define silicon-controlled rectifiers and thyristors as synonymous while other sources define silicon-controlled rectifiers as a proper subset of the set of thyristors; the latter being devices with at least four layers of alternating n- and p-type material. Accor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autotransformer
An autotransformer is an electrical transformer with only one winding. The "auto" (Greek for "self") prefix refers to the single coil acting alone, not to any kind of automatic mechanism. In an autotransformer, portions of the same winding act as both the primary winding and secondary winding sides of the transformer. In contrast, an ordinary transformer has separate primary and secondary windings which have no metallic conducting path between them. The autotransformer winding has at least three taps where electrical connections are made. Since part of the winding does "double duty", autotransformers have the advantages of often being smaller, lighter, and cheaper than typical dual-winding transformers, but the disadvantage of not providing electrical isolation between primary and secondary circuits. Other advantages of autotransformers include lower leakage reactance, lower losses, lower excitation current, and increased VA rating for a given size and mass. An example of an ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axle Load
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearings or bushings are provided at the mounting points where the axle is supported. In the latter case, a bearing or bushing sits inside a central hole in the wheel to allow the wheel or gear to rotate around the axle. Sometimes, especially on bicycles, the latter type axle is referred to as a ''spindle''. Terminology On cars and trucks, several senses of the word ''axle'' occur in casual usage, referring to the shaft itself, its housing, or simply any transverse pair of wheels. Strictly speaking, a shaft which rotates with the wheel, being either bolted or splined in fixed relation to it, is called an ''axle'' or ''axle shaft''. However, in looser usage, an entire assembly including the surrounding axle housing (typically a casting) is als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotary Converter
A rotary converter is a type of electrical machine which acts as a mechanical rectifier, inverter or frequency converter. Rotary converters were used to convert alternating current (AC) to direct current (DC), or DC to AC power, before the advent of chemical or solid state power rectification and inverting. They were commonly used to provide DC power for commercial, industrial and railway electrification from an AC power source. Principles of operation The rotary converter can be thought of as a motor-generator, where the two machines share a single rotating armature and set of field coils. The basic construction of the rotary converter consists of a DC generator (dynamo) with a set of slip rings tapped into its rotor windings at evenly spaced intervals. When a dynamo is spun the electric currents in its rotor windings alternate as it rotates in the magnetic field of the stationary field windings. This alternating current is rectified by means of a commutator, which all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rectifier
A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The reverse operation (converting DC to AC) is performed by an Power inverter, inverter. The process is known as ''rectification'', since it "straightens" the direction of current. Physically, rectifiers take a number of forms, including Vacuum tube#Diodes, vacuum tube diodes, wet chemical cells, mercury-arc valves, stacks of copper and selenium rectifier, selenium oxide plates, Diode#Semiconductor diodes, semiconductor diodes, silicon-controlled rectifiers and other silicon-based semiconductor switches. Historically, even synchronous electromechanical switches and motor-generator sets have been used. Early radio receivers, called crystal radios, used a "Cat's-whisker detector, cat's whisker" of fine wire pressing on a crystal of galena (lead sulfide) to serve as a point-contact rectifier or "crystal detec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ignitron
An ignitron is a type of gas-filled tube used as a controlled rectifier and dating from the 1930s. Invented by Joseph Slepian while employed by Westinghouse, Westinghouse was the original manufacturer and owned trademark rights to the name "Ignitron". Ignitrons are closely related to mercury-arc valves but differ in the way the arc is ignited. They function similarly to thyratrons; a triggering pulse to the igniter electrode turns the device "on", allowing a high current to flow between the cathode and anode electrodes. After it is turned on, the current through the anode must be reduced to zero to restore the device to its nonconducting state. They are used to switch high currents in heavy industrial applications. Construction and operation An ignitron is usually a large steel container with a pool of mercury in the bottom that acts as a cathode during operation. A large graphite or refractory metal cylinder, held above the pool by an insulated electrical connection, serves as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valenciennes
Valenciennes (, also , , ; nl, label=also Dutch, Valencijn; pcd, Valincyinnes or ; la, Valentianae) is a commune in the Nord department, Hauts-de-France, France. It lies on the Scheldt () river. Although the city and region experienced a steady population decline between 1975 and 1990, it has since rebounded. The 1999 census recorded that the population of the commune of Valenciennes was 41,278, and that of the metropolitan area was 399,677. History Before 1500 Valenciennes is first mentioned in 693 in a legal document written by Clovis II (''Valentiana''). In the 843 Treaty of Verdun, it was made a neutral city between Neustria and the Austrasia. Later in the 9th century the region was overrun by the Normans, and in 881 the town passed to them. In 923 it passed to the Duchy of Lower Lotharingia dependent on the Holy Roman Empire. Once the Empire of the Franks was established, the city began to develop, though the archaeological record has still not revealed all it has to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thionville
Thionville (; ; german: Diedenhofen ) is a city in the northeastern French department of Moselle. The city is located on the left bank of the river Moselle, opposite its suburb Yutz. History Thionville was settled as early as the time of the Merovingians. After the fall of the Western Roman Empire, the region was inhabited by the Germanic Alamanni. It was known in the Latin of that era as ''Theudonevilla'' or ''Totonisvilla''. King Pepin the Short had a royal palace constructed here. The Synod of Thionville was held here beginning on February 2, 835. It reinstated Emperor Louis the Pious and reversed his former conviction on crimes — none of which he actually committed — and deposed the Archbishop of Rheims, Ebbo. The Synod was composed of 43 bishops. On February 28, 835, in Mainz, Ebbo admitted that Louis had not committed the crimes of which he had been indicted and for which he had been deposed as Holy Roman Emperor. From the 10th century onward, the area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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