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  2. Overhead line - Wikipedia

    en.wikipedia.org/wiki/Overhead_line

    The installation of overhead lines may require reconstruction of bridges to provide safe electrical clearance. [20] Overhead lines, like most electrified systems, require a greater capital expenditure when building the system than an equivalent non-electric system. While a unelectrified railway line requires only the grade, ballast, ties and ...

  3. 25 kV AC railway electrification - Wikipedia

    en.wikipedia.org/wiki/25_kV_AC_railway...

    The overhead line (3) and feeder (5) are on opposite phases so the voltage between them is 50 kV, while the voltage between the overhead line (3) and the running rails (4) remains at 25 kV. Periodic autotransformers (9) divert the return current from the neutral rail, step it up, and send it along the feeder line.

  4. Overhead power line - Wikipedia

    en.wikipedia.org/wiki/Overhead_power_line

    Train power. Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains. Overhead line is designed on the principle of one or more overhead wires situated over rail tracks. Feeder stations at regular intervals along the overhead line supply power from the high-voltage grid.

  5. Stepped reckoner - Wikipedia

    en.wikipedia.org/wiki/Stepped_reckoner

    The stepped reckoner or Leibniz calculator was a mechanical calculator invented by the German mathematician Gottfried Wilhelm Leibniz (started in 1673, when he presented a wooden model to the Royal Society of London [2] and completed in 1694). [1] The name comes from the translation of the German term for its operating mechanism, Staffelwalze ...

  6. Electric power transmission - Wikipedia

    en.wikipedia.org/wiki/Electric_power_transmission

    The combined transmission and distribution network is part of electricity delivery, known as the electrical grid. Efficient long-distance transmission of electric power requires high voltages. This reduces the losses produced by strong currents. Transmission lines use either alternating current (AC) or direct current (DC).

  7. Railroad electrification in the United States - Wikipedia

    en.wikipedia.org/wiki/Railroad_electrification...

    The New Haven chose the 11 kV 25 Hz system, later used by the PRR, in addition to working with Westinghouse to develop AC/DC electric motors (locomotives) to run on both AC overhead lines and DC third rail. The main line, now Metro-North Railroad's New Haven Line, was converted to 12.5 kV 60 Hz in 1985.

  8. Liverpool Overhead Railway - Wikipedia

    en.wikipedia.org/wiki/Liverpool_Overhead_Railway

    The Liverpool Overhead Railway (known locally as the Dockers' Umbrella or Ovee) was an overhead railway in Liverpool that operated along the Liverpool Docks and opened in 1893 with lightweight electric multiple units. The railway had a number of world firsts: it was the first electric elevated railway, the first to use automatic signalling ...

  9. Railway electrification - Wikipedia

    en.wikipedia.org/wiki/Railway_electrification

    Railway electrification is the use of electric power for the propulsion of rail transport. Electric railways use either electric locomotives (hauling passengers or freight in separate cars), electric multiple units (passenger cars with their own motors) or both. Electricity is typically generated in large and relatively efficient generating ...