It is a device used in electrical work. It is used to change the intensity of the current. There are two main types as "sliding" and "with lamp". In all of these, the main is to change the intensity of the electric current by lengthening and shortening the conductor. For example, the arm in front of the vatman on the trams is the arm of a large rheostat. By moving this arm, Vatman adjusts the intensity of the current, thus adjusting the speed of the tram. The short circuit principle applies. Since the current always prefers the path with the least resistance, the resistance is decreased and the current intensity is increased by using the path that is adjusted.
Where is rheostat used?
1. In laboratories, etalon is used as a resistor, that is, in the adjustment of resistance values,
2. In the resistance measurements in the bridge method,
3. In circuit experiments that require variable resistance,
4. When extracting diode and transistor characteristic curves, changing input and output voltages and currents, and many other operations that require variable resistance,
5. On the adjustment buttons of electric stoves,
6. It is used in washing machines, dishwashers, etc. electronic goods.
Why was the Rheostat System Used in the Electric Tram?
In 1881, the electric tram, developed by the German electrical engineer and industrialist Werner von Siemens (1816-1892), was put into service on the Berlin-Lichterfelde trial line. In the 19th century, the population of Peris increased 4 times, London 5 times, Berlin 9 times. In rapidly growing cities, horse-drawn trams were used for urban transportation, the first horse-drawn tram was put into operation in New York in the middle of the 19th century. The tram occupied a very important place in city life, in 1882 alone 65 million passengers were transported by horse-drawn tram in Berlin. But due to the increasing population and accelerating pace of life, horse-drawn trams could not meet the need, so faster and more powerful means of transportation were sought.
The electric current required for the 110-volt electric motor that Siemens attached to a horse-drawn tram was supplied by rails. However, electrifying both rails was a danger to pedestrians and the horses pulling the horse-drawn tram. As a matter of fact, in this period when horse-drawn trams were used, the horses stepping on both of the electrified rails were paying for their "missteps" with their lives. Inefficient accumulators installed on trams instead of supplying current to the rails also had to be recharged at short intervals.
Finally, with the discovery of overhead lines, the electricity problem was solved. In 1888, trams that received electricity from the overhead line with a metal extension called a horn and whose speed could be adjusted with a rheostat mechanism were put into service in Richmond (Virginia / USA). In 1889, the number of electric trams operating in US cities increased to 109, and the total length of the lines was approximately 1000 km.
In 1869, the horse-drawn tramway had almost completely replaced the urban transportation in the USA, and the total length of the tram network was 20 thousand km. In Europe, on the other hand, the electric tram did not become widespread at the beginning due to the reactions arising from the electricity hazard. In 1899, the total length of electric tram lines in European cities was 7 thousand kilometers.
In the 1930s, buses and metro began to replace the tram in urban transportation. In the early 1950s, tram lines were closed in major cities such as London and Paris.
The horse-drawn tram in Turkey entered service in Istanbul in 1871 and was electrified in 1909. In Istanbul, the tram was removed on the European side in 1961 and on the Anatolian side in 1966. In 1990, a tram line was laid again between Tünel and Taksim in Beyoğlu.