Comment, Like, & Favorite
The first transmission of electrical impulses over an extended distance was demonstrated on July 14, 1729 by the physicist Stephen Gray. The demonstration used damp hemp cords suspended by silk threads (the low resistance of metallic conductors not being appreciated at the time).
However the first practical use of overhead lines was in the context of telegraphy. By 1837 experimental commercial telegraph systems ran as far as 13 miles (20 km). Electric power transmission was accomplished in 1882 with the first high voltage transmission between Munich and Miesbach. 1891 saw the construction of the first three-phase alternating current overhead line on the occasion of the International Electricity Exhibition in Frankfurt, between Lauffen and Frankfurt.
In 1912 the first 110 kV-overhead power line entered service followed by the first 220 kV-overhead power line in 1923. In the 1920s RWE AG built the first overhead line for this voltage and in 1926 built a Rhine crossing with the pylons of Voerde, two masts 138 meters high.
In 1953, the first 345 kV line was put into service by American Electric Power in the United States. In Germany in 1957 the first 380 kV overhead power line was commissioned (between the transformer station and Rommerskirchen). In the same year the overhead line traversing of the Strait of Messina went into service in Italy, whose pylons served the Elbe crossing 1. This was used as the model for the building of the Elbe crossing 2 in the second half of the 1970s which saw the construction of the highest overhead line pylons of the world. Earlier, in 1952, the first 400 kv line was put into service in Sweden, in 100 miles between the more populated areas in the south and the largest hydroelectric power stations in the north. Starting from 1967 in Russia, and also in the USA and Canada, overhead lines for voltage of 765 kV were built. In 1982 overhead power lines were built in Russia between Elektrostal and the power station at Ekibastusz, this was a three-phase alternating current line at 1150 kV (Powerline Ekibastuz-Kokshetau). In 1999, in Japan the first powerline designed for 1000 kV with 2 circuits were built, the Kita-Iwaki Powerline. In 2003 the building of the highest overhead line commenced in China, the Yangtze River Crossing.
November 4th, 2012
Viewed 9 Times - Last Visitor from Vineyard Haven, MA on 02/26/2014 at 12:01 AM
copy and paste to your website / blog - preview
powerful framed prints, power framed prints, pollution framed prints, sky framed prints, silhouette framed prints, pylon framed prints, metal framed prints, line framed prints, industry framed prints, pole framed prints, plant framed prints, mountain framed prints, station framed prints, volt framed prints, utility framed prints, transmission framed prints, wire framed prints, watt framed prints, voltage framed prints, supply framed prints, structure framed prints, steel framed prints, tower framed prints, technology framed prints, tall framed prints, powerful greeting cards, power greeting cards, pollution greeting cards, sky greeting cards, silhouette greeting cards, pylon greeting cards, metal greeting cards, line greeting cards, industry greeting cards, pole greeting cards, plant greeting cards, mountain greeting cards, station greeting cards, volt greeting cards, utility greeting cards, transmission greeting cards, wire greeting cards, watt greeting cards, voltage greeting cards, supply greeting cards, structure greeting cards, steel greeting cards, tower greeting cards, technology greeting cards, tall greeting cards, powerful prints, power prints, pollution prints, sky prints, silhouette prints, pylon prints, metal prints, line prints, industry prints, pole prints, plant prints, mountain prints, station prints, volt prints, utility prints, transmission prints, wire prints, watt prints, voltage prints, supply prints, structure prints, steel prints, tower prints, technology prints, tall prints, powerful posters, power posters, pollution posters, sky posters, silhouette posters, pylon posters, metal posters, line posters, industry posters, pole posters, plant posters, mountain posters, station posters, volt posters, utility posters, transmission posters, wire posters, watt posters, voltage posters, supply posters, structure posters, steel posters, tower posters, technology posters, tall posters