id stringlengths 24 24 | question stringlengths 1 270 | answer stringlengths 1 239 | documents listlengths 1 1 |
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572f2eff04bcaa1900d76775 | What type is mostly used third rail or overhead wires? | overhead wires | [
"Railway_electrification_system\n\nMost electrification systems use overhead wires, but third rail is an option up to about 1,200 V. Third rail systems exclusively use DC distribution. The use of AC is not feasible because the dimensions of a third rail are physically very large compared with the skin depth that th... |
572f2eff04bcaa1900d76776 | Is trird rail system being used exclusively with AC or DC ? | DC distribution | [
"Railway_electrification_system\n\nMost electrification systems use overhead wires, but third rail is an option up to about 1,200 V. Third rail systems exclusively use DC distribution. The use of AC is not feasible because the dimensions of a third rail are physically very large compared with the skin depth that th... |
572f2eff04bcaa1900d76777 | What depth does the alternating current penetrate in a steel rail? | skin depth | [
"Railway_electrification_system\n\nMost electrification systems use overhead wires, but third rail is an option up to about 1,200 V. Third rail systems exclusively use DC distribution. The use of AC is not feasible because the dimensions of a third rail are physically very large compared with the skin depth that th... |
572f2eff04bcaa1900d76778 | What is physically more compact tird rail or overhead wires? | Third rail | [
"Railway_electrification_system\n\nMost electrification systems use overhead wires, but third rail is an option up to about 1,200 V. Third rail systems exclusively use DC distribution. The use of AC is not feasible because the dimensions of a third rail are physically very large compared with the skin depth that th... |
572f2eff04bcaa1900d76779 | What is more prefferable for subway lines? | Third rail | [
"Railway_electrification_system\n\nMost electrification systems use overhead wires, but third rail is an option up to about 1,200 V. Third rail systems exclusively use DC distribution. The use of AC is not feasible because the dimensions of a third rail are physically very large compared with the skin depth that th... |
572f3099a23a5019007fc4c5 | Why DC system can effect the speed of trains? | low voltages | [
"Railway_electrification_system\n\nDC systems (especially third-rail systems) are limited to relatively low voltages and this can limit the size and speed of trains and cannot use low-level platform and also limit the amount of air-conditioning that the trains can provide. This may be a factor favouring overhead wi... |
572f3099a23a5019007fc4c6 | Can DC systems use low-level platform? | cannot | [
"Railway_electrification_system\n\nDC systems (especially third-rail systems) are limited to relatively low voltages and this can limit the size and speed of trains and cannot use low-level platform and also limit the amount of air-conditioning that the trains can provide. This may be a factor favouring overhead wi... |
572f3099a23a5019007fc4c7 | Besides speed and size what else the low voltage of DC system can effect? | air-conditioning | [
"Railway_electrification_system\n\nDC systems (especially third-rail systems) are limited to relatively low voltages and this can limit the size and speed of trains and cannot use low-level platform and also limit the amount of air-conditioning that the trains can provide. This may be a factor favouring overhead wi... |
572f3099a23a5019007fc4c8 | What is the speed limit for third rail system trains? | 160 km/h | [
"Railway_electrification_system\n\nDC systems (especially third-rail systems) are limited to relatively low voltages and this can limit the size and speed of trains and cannot use low-level platform and also limit the amount of air-conditioning that the trains can provide. This may be a factor favouring overhead wi... |
572f3099a23a5019007fc4c9 | What can become unreliable if the speed exceeds the limit of 100 mph for DC system trains? | contact between the shoe and the rail | [
"Railway_electrification_system\n\nDC systems (especially third-rail systems) are limited to relatively low voltages and this can limit the size and speed of trains and cannot use low-level platform and also limit the amount of air-conditioning that the trains can provide. This may be a factor favouring overhead wi... |
572f3315b2c2fd1400567f77 | What is the other name for the street trams? | streetcars | [
"Railway_electrification_system\n\nSome street trams (streetcars) used conduit third-rail current collection. The third rail was below street level. The tram picked up the current through a plough (U.S. \"plow\") accessed through a narrow slot in the road. In the United States, much (though not all) of the former s... |
572f3315b2c2fd1400567f78 | Where is third rail situated in the street trams system? | below street level | [
"Railway_electrification_system\n\nSome street trams (streetcars) used conduit third-rail current collection. The third rail was below street level. The tram picked up the current through a plough (U.S. \"plow\") accessed through a narrow slot in the road. In the United States, much (though not all) of the former s... |
572f3315b2c2fd1400567f79 | What area in US discontinued using overhead wires for streetcars in 1962? | Washington, D.C. | [
"Railway_electrification_system\n\nSome street trams (streetcars) used conduit third-rail current collection. The third rail was below street level. The tram picked up the current through a plough (U.S. \"plow\") accessed through a narrow slot in the road. In the United States, much (though not all) of the former s... |
572f3315b2c2fd1400567f7a | What external and weather factors can effect conduit slot? | leaves and snow | [
"Railway_electrification_system\n\nSome street trams (streetcars) used conduit third-rail current collection. The third rail was below street level. The tram picked up the current through a plough (U.S. \"plow\") accessed through a narrow slot in the road. In the United States, much (though not all) of the former s... |
572f3315b2c2fd1400567f7b | What are the main reasons the conduit lines were converted to overhead wire system? | cost and operating efficiency | [
"Railway_electrification_system\n\nSome street trams (streetcars) used conduit third-rail current collection. The third rail was below street level. The tram picked up the current through a plough (U.S. \"plow\") accessed through a narrow slot in the road. In the United States, much (though not all) of the former s... |
572f3f3404bcaa1900d767c5 | What year the "second generation" of tram system began to operate in France? | 2003 | [
"Railway_electrification_system\n\nA new approach to avoiding overhead wires is taken by the \"second generation\" tram/streetcar system in Bordeaux, France (entry into service of the first line in December 2003; original system discontinued in 1958) with its APS (alimentation par sol – ground current feed). This i... |
572f3f3404bcaa1900d767c6 | When was the original system discontinued? | 1958 | [
"Railway_electrification_system\n\nA new approach to avoiding overhead wires is taken by the \"second generation\" tram/streetcar system in Bordeaux, France (entry into service of the first line in December 2003; original system discontinued in 1958) with its APS (alimentation par sol – ground current feed). This i... |
572f3f3404bcaa1900d767c7 | How is the circuit of the third rail divided? | energized segment | [
"Railway_electrification_system\n\nA new approach to avoiding overhead wires is taken by the \"second generation\" tram/streetcar system in Bordeaux, France (entry into service of the first line in December 2003; original system discontinued in 1958) with its APS (alimentation par sol – ground current feed). This i... |
572f3f3404bcaa1900d767c8 | Does energized segment of third rail pose the threat to pedestrians if uncovered? | no danger | [
"Railway_electrification_system\n\nA new approach to avoiding overhead wires is taken by the \"second generation\" tram/streetcar system in Bordeaux, France (entry into service of the first line in December 2003; original system discontinued in 1958) with its APS (alimentation par sol – ground current feed). This i... |
572f40f1b2c2fd1400567f9f | What type of system does London Underground use? | four-rail system | [
"Railway_electrification_system\n\nThe London Underground in England is one of the few networks that uses a four-rail system. The additional rail carries the electrical return that, on third rail and overhead networks, is provided by the running rails. On the London Underground, a top-contact third rail is beside t... |
572f40f1b2c2fd1400567fa0 | What is the purpose of the forth rail? | carries the electrical return | [
"Railway_electrification_system\n\nThe London Underground in England is one of the few networks that uses a four-rail system. The additional rail carries the electrical return that, on third rail and overhead networks, is provided by the running rails. On the London Underground, a top-contact third rail is beside t... |
572f40f1b2c2fd1400567fa1 | What is the volatage surge of the third rail of London Underground system? | +420v DC | [
"Railway_electrification_system\n\nThe London Underground in England is one of the few networks that uses a four-rail system. The additional rail carries the electrical return that, on third rail and overhead networks, is provided by the running rails. On the London Underground, a top-contact third rail is beside t... |
572f40f1b2c2fd1400567fa2 | What is the voltage of the return rail? | −210v DC | [
"Railway_electrification_system\n\nThe London Underground in England is one of the few networks that uses a four-rail system. The additional rail carries the electrical return that, on third rail and overhead networks, is provided by the running rails. On the London Underground, a top-contact third rail is beside t... |
572f40f1b2c2fd1400567fa3 | Where was the system similar to London Underground used as well? | Milan | [
"Railway_electrification_system\n\nThe London Underground in England is one of the few networks that uses a four-rail system. The additional rail carries the electrical return that, on third rail and overhead networks, is provided by the running rails. On the London Underground, a top-contact third rail is beside t... |
572f42c2947a6a140053c81e | What is the crucial advantage of four-rail system? | running rail carries any current | [
"Railway_electrification_system\n\nThe key advantage of the four-rail system is that neither running rail carries any current. This scheme was introduced because of the problems of return currents, intended to be carried by the earthed (grounded) running rail, flowing through the iron tunnel linings instead. This c... |
572f42c2947a6a140053c81f | What danger can return currents cause? | electrolytic damage | [
"Railway_electrification_system\n\nThe key advantage of the four-rail system is that neither running rail carries any current. This scheme was introduced because of the problems of return currents, intended to be carried by the earthed (grounded) running rail, flowing through the iron tunnel linings instead. This c... |
572f42c2947a6a140053c820 | How did return current effect water and gas in iron pipes? | water and gas mains | [
"Railway_electrification_system\n\nThe key advantage of the four-rail system is that neither running rail carries any current. This scheme was introduced because of the problems of return currents, intended to be carried by the earthed (grounded) running rail, flowing through the iron tunnel linings instead. This c... |
572f42c2947a6a140053c821 | How are stray earth currents kept to a manageable levels? | by using resistors | [
"Railway_electrification_system\n\nThe key advantage of the four-rail system is that neither running rail carries any current. This scheme was introduced because of the problems of return currents, intended to be carried by the earthed (grounded) running rail, flowing through the iron tunnel linings instead. This c... |
572f42c2947a6a140053c822 | What insures minimal current leak during power rails instalation? | ceramic chairs | [
"Railway_electrification_system\n\nThe key advantage of the four-rail system is that neither running rail carries any current. This scheme was introduced because of the problems of return currents, intended to be carried by the earthed (grounded) running rail, flowing through the iron tunnel linings instead. This c... |
572f447f947a6a140053c844 | What is the voltage shared two types of trains UK railroad system? | 660 V | [
"Railway_electrification_system\n\nOn tracks that London Underground share with National Rail third-rail stock (the Bakerloo and District lines both have such sections), the centre rail is connected to the running rails, allowing both types of train to operate, at a compromise voltage of 660 V. Underground trains p... |
572f447f947a6a140053c845 | Why some sections of Bakerloo and District lines were rewired to three-rail system? | to simplify rolling stock use | [
"Railway_electrification_system\n\nOn tracks that London Underground share with National Rail third-rail stock (the Bakerloo and District lines both have such sections), the centre rail is connected to the running rails, allowing both types of train to operate, at a compromise voltage of 660 V. Underground trains p... |
572f447f947a6a140053c846 | How did it become possible to share the voltage for different types of train? | the centre rail is connected to the running rails | [
"Railway_electrification_system\n\nOn tracks that London Underground share with National Rail third-rail stock (the Bakerloo and District lines both have such sections), the centre rail is connected to the running rails, allowing both types of train to operate, at a compromise voltage of 660 V. Underground trains p... |
572f4794b2c2fd1400567fc7 | Why some lines of Paris Metro have to operate on a four-rail system? | rubber tyres | [
"Railway_electrification_system\n\nA few lines of the Paris Métro in France operate on a four-rail power scheme because they run on rubber tyres which run on a pair of narrow roadways made of steel and, in some places, concrete. Since the tyres do not conduct the return current, the two guide rails provided outside... |
572f4794b2c2fd1400567fc8 | What was the solution for the return current problem in Paris Metro? | two guide rails | [
"Railway_electrification_system\n\nA few lines of the Paris Métro in France operate on a four-rail power scheme because they run on rubber tyres which run on a pair of narrow roadways made of steel and, in some places, concrete. Since the tyres do not conduct the return current, the two guide rails provided outside... |
572f4794b2c2fd1400567fc9 | What is required in order for the guide rails to operate properly? | a single polarity supply | [
"Railway_electrification_system\n\nA few lines of the Paris Métro in France operate on a four-rail power scheme because they run on rubber tyres which run on a pair of narrow roadways made of steel and, in some places, concrete. Since the tyres do not conduct the return current, the two guide rails provided outside... |
572f4794b2c2fd1400567fca | How train is able to turn around after each completed journey? | reversing loops | [
"Railway_electrification_system\n\nA few lines of the Paris Métro in France operate on a four-rail power scheme because they run on rubber tyres which run on a pair of narrow roadways made of steel and, in some places, concrete. Since the tyres do not conduct the return current, the two guide rails provided outside... |
572f4794b2c2fd1400567fcb | Why was the reversing loop created? | having to 'run around' the rest of the train | [
"Railway_electrification_system\n\nA few lines of the Paris Métro in France operate on a four-rail power scheme because they run on rubber tyres which run on a pair of narrow roadways made of steel and, in some places, concrete. Since the tyres do not conduct the return current, the two guide rails provided outside... |
572f498104bcaa1900d76817 | What was a disadvantage of DC system? | power-wasting resistors | [
"Railway_electrification_system\n\nAn early advantage of AC is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driv... |
572f498104bcaa1900d76818 | How can different range of voltages be supplied for AC locomotives? | multiple taps on the transformer | [
"Railway_electrification_system\n\nAn early advantage of AC is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driv... |
572f498104bcaa1900d76819 | What taps can provide lighting supply? | low-voltage transformer windings | [
"Railway_electrification_system\n\nAn early advantage of AC is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driv... |
572f498104bcaa1900d7681a | What will AC/DC motor be replaced with? | three-phase induction motor | [
"Railway_electrification_system\n\nAn early advantage of AC is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driv... |
572f498104bcaa1900d7681b | What is the main advantage of an induction motor? | can run equally well on DC or AC of any frequency | [
"Railway_electrification_system\n\nAn early advantage of AC is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driv... |
572f4ab9b2c2fd1400567fef | How can DC motor turn universal? | if fitted with laminated pole pieces | [
"Railway_electrification_system\n\nDC commutating electric motors, if fitted with laminated pole pieces, become universal motors because they can also operate on AC; reversing the current in both stator and rotor does not reverse the motor. But the now-standard AC distribution frequencies of 50 and 60 Hz caused dif... |
572f4ab9b2c2fd1400567ff0 | What problems did AC distribution cause? | inductive reactance and eddy current losses | [
"Railway_electrification_system\n\nDC commutating electric motors, if fitted with laminated pole pieces, become universal motors because they can also operate on AC; reversing the current in both stator and rotor does not reverse the motor. But the now-standard AC distribution frequencies of 50 and 60 Hz caused dif... |
572f4ab9b2c2fd1400567ff1 | How do railways try to solve the problem of inductive reactance of AC system? | low AC frequencies | [
"Railway_electrification_system\n\nDC commutating electric motors, if fitted with laminated pole pieces, become universal motors because they can also operate on AC; reversing the current in both stator and rotor does not reverse the motor. But the now-standard AC distribution frequencies of 50 and 60 Hz caused dif... |
572f4ab9b2c2fd1400567ff2 | How can low frequencies be obtained? | converted from utility power | [
"Railway_electrification_system\n\nDC commutating electric motors, if fitted with laminated pole pieces, become universal motors because they can also operate on AC; reversing the current in both stator and rotor does not reverse the motor. But the now-standard AC distribution frequencies of 50 and 60 Hz caused dif... |
572f4cdaa23a5019007fc501 | How did non-standard gauge trains start to operate with high-voltage AC? | adopting the already proven RhB system. | [
"Railway_electrification_system\n\nHigh-voltage AC overhead systems are not only for standard gauge national networks. The meter gauge Rhaetian Railway (RhB) and the neighbouring Matterhorn Gotthard Bahn (MGB) operate on 11 kV at 16.7 Hz frequency. Practice has proven that both Swiss and German 15 kV trains can ope... |
572f4cdaa23a5019007fc502 | When was the first trail of RhB system tested? | 1913 | [
"Railway_electrification_system\n\nHigh-voltage AC overhead systems are not only for standard gauge national networks. The meter gauge Rhaetian Railway (RhB) and the neighbouring Matterhorn Gotthard Bahn (MGB) operate on 11 kV at 16.7 Hz frequency. Practice has proven that both Swiss and German 15 kV trains can ope... |
572f4ec3a23a5019007fc505 | What frequency was typically used on US Amtrak? | 25 Hz | [
"Railway_electrification_system\n\nIn the United States, 25 Hz, a once-common industrial power frequency is used on Amtrak's 25 Hz traction power system at 12 kV on the Northeast Corridor between Washington, D.C. and New York City and on the Keystone Corridor between Harrisburg, Pennsylvania and Philadelphia. SEPTA... |
572f4ec3a23a5019007fc506 | What voltage does SEPTA system use? | 12 kV voltage | [
"Railway_electrification_system\n\nIn the United States, 25 Hz, a once-common industrial power frequency is used on Amtrak's 25 Hz traction power system at 12 kV on the Northeast Corridor between Washington, D.C. and New York City and on the Keystone Corridor between Harrisburg, Pennsylvania and Philadelphia. SEPTA... |
572f4ec3a23a5019007fc507 | What specification is similar for both Amtrak and Septa systems? | catenary voltage | [
"Railway_electrification_system\n\nIn the United States, 25 Hz, a once-common industrial power frequency is used on Amtrak's 25 Hz traction power system at 12 kV on the Northeast Corridor between Washington, D.C. and New York City and on the Keystone Corridor between Harrisburg, Pennsylvania and Philadelphia. SEPTA... |
572f4ec3a23a5019007fc508 | When was a 11kV system of NY, New Haven and Hartford was converted to 12.5 kV? | 1987 | [
"Railway_electrification_system\n\nIn the United States, 25 Hz, a once-common industrial power frequency is used on Amtrak's 25 Hz traction power system at 12 kV on the Northeast Corridor between Washington, D.C. and New York City and on the Keystone Corridor between Harrisburg, Pennsylvania and Philadelphia. SEPTA... |
572f506a04bcaa1900d76841 | When was overhead wires system being used for the first time in UK? | 1 December 1909 | [
"Railway_electrification_system\n\nIn the UK, the London, Brighton and South Coast Railway pioneered overhead electrification of its suburban lines in London, London Bridge to Victoria being opened to traffic on 1 December 1909. Victoria to Crystal Palace via Balham and West Norwood opened in May 1911. Peckham Rye ... |
572f506a04bcaa1900d76842 | What line used the overhead wire system first Victoria to Crystal Palace or Peckham Rye to West Noorwood? | Victoria to Crystal Palace | [
"Railway_electrification_system\n\nIn the UK, the London, Brighton and South Coast Railway pioneered overhead electrification of its suburban lines in London, London Bridge to Victoria being opened to traffic on 1 December 1909. Victoria to Crystal Palace via Balham and West Norwood opened in May 1911. Peckham Rye ... |
572f506a04bcaa1900d76843 | What was the cause of lines not being extended? | the First World War | [
"Railway_electrification_system\n\nIn the UK, the London, Brighton and South Coast Railway pioneered overhead electrification of its suburban lines in London, London Bridge to Victoria being opened to traffic on 1 December 1909. Victoria to Crystal Palace via Balham and West Norwood opened in May 1911. Peckham Rye ... |
572f506a04bcaa1900d76844 | What voltage was used in the two lines opened in 1925 of Southern Railway? | 6.7 kV 25 Hz | [
"Railway_electrification_system\n\nIn the UK, the London, Brighton and South Coast Railway pioneered overhead electrification of its suburban lines in London, London Bridge to Victoria being opened to traffic on 1 December 1909. Victoria to Crystal Palace via Balham and West Norwood opened in May 1911. Peckham Rye ... |
572f52bc04bcaa1900d76849 | What countries used three-phase AC system in the the beginning of 20th century? | Italy, Switzerland and the United States | [
"Railway_electrification_system\n\nThree-phase AC railway electrification was used in Italy, Switzerland and the United States in the early twentieth century. Italy was the major user, for lines in the mountainous regions of northern Italy from 1901 until 1976. The first lines were the Burgdorf-Thun line in Switzer... |
572f52bc04bcaa1900d7684a | What country was a bigger user compare to the three of them? | Italy | [
"Railway_electrification_system\n\nThree-phase AC railway electrification was used in Italy, Switzerland and the United States in the early twentieth century. Italy was the major user, for lines in the mountainous regions of northern Italy from 1901 until 1976. The first lines were the Burgdorf-Thun line in Switzer... |
572f52bc04bcaa1900d7684b | Where did Italy start using the AC system? | in the mountainous regions of northern Italy | [
"Railway_electrification_system\n\nThree-phase AC railway electrification was used in Italy, Switzerland and the United States in the early twentieth century. Italy was the major user, for lines in the mountainous regions of northern Italy from 1901 until 1976. The first lines were the Burgdorf-Thun line in Switzer... |
572f52bc04bcaa1900d7684c | How long did the AC system last in northern Italy? | 1901 until 1976 | [
"Railway_electrification_system\n\nThree-phase AC railway electrification was used in Italy, Switzerland and the United States in the early twentieth century. Italy was the major user, for lines in the mountainous regions of northern Italy from 1901 until 1976. The first lines were the Burgdorf-Thun line in Switzer... |
572f52bc04bcaa1900d7684d | How long did three-phase system operate in Cascade Tunnel? | 1909 to 1927 | [
"Railway_electrification_system\n\nThree-phase AC railway electrification was used in Italy, Switzerland and the United States in the early twentieth century. Italy was the major user, for lines in the mountainous regions of northern Italy from 1901 until 1976. The first lines were the Burgdorf-Thun line in Switzer... |
572f54f7b2c2fd140056802b | What country has first tried to use single-phase AC? | Hungary | [
"Railway_electrification_system\n\nThe first attempts to use standard-frequency single-phase AC were made in Hungary as far back as 1923, by the Hungarian Kálmán Kandó on the line between Budapest-Nyugati and Alag, using 16 kV at 50 Hz. The locomotives carried a four-pole rotating phase converter feeding a single t... |
572f54f7b2c2fd140056802c | What frequency did the line of Hungarian rail system used in 1923? | 16 kV at 50 Hz | [
"Railway_electrification_system\n\nThe first attempts to use standard-frequency single-phase AC were made in Hungary as far back as 1923, by the Hungarian Kálmán Kandó on the line between Budapest-Nyugati and Alag, using 16 kV at 50 Hz. The locomotives carried a four-pole rotating phase converter feeding a single t... |
572f54f7b2c2fd140056802d | What type of the converter was used in hungarian locomotives of that time? | four-pole rotating phase converter | [
"Railway_electrification_system\n\nThe first attempts to use standard-frequency single-phase AC were made in Hungary as far back as 1923, by the Hungarian Kálmán Kandó on the line between Budapest-Nyugati and Alag, using 16 kV at 50 Hz. The locomotives carried a four-pole rotating phase converter feeding a single t... |
572f54f7b2c2fd140056802e | How could the locomotives run on four speed levels? | motor could be changed using slip rings | [
"Railway_electrification_system\n\nThe first attempts to use standard-frequency single-phase AC were made in Hungary as far back as 1923, by the Hungarian Kálmán Kandó on the line between Budapest-Nyugati and Alag, using 16 kV at 50 Hz. The locomotives carried a four-pole rotating phase converter feeding a single t... |
572f54f7b2c2fd140056802f | What system was adopted in Hungary after WWII? | Russian | [
"Railway_electrification_system\n\nThe first attempts to use standard-frequency single-phase AC were made in Hungary as far back as 1923, by the Hungarian Kálmán Kandó on the line between Budapest-Nyugati and Alag, using 16 kV at 50 Hz. The locomotives carried a four-pole rotating phase converter feeding a single t... |
572f575504bcaa1900d76863 | What was the main requirement for electric feeder stations? | line fed from different feeder stations must be kept strictly isolated | [
"Railway_electrification_system\n\nTo prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typical... |
572f575504bcaa1900d76864 | What invention prevented lines from getting mixed? | Phase Breaks | [
"Railway_electrification_system\n\nTo prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typical... |
572f575504bcaa1900d76865 | What was the part of wire in Phase Break sections an arc being drawn from one wire to another? | The earthed section | [
"Railway_electrification_system\n\nTo prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typical... |
572f575504bcaa1900d76866 | How were the drivers warned to start coasting the train? | warning board | [
"Railway_electrification_system\n\nTo prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typical... |
572f575504bcaa1900d76867 | What should the driver do in order to open and close the circuit breaker? | to shut off power and coast | [
"Railway_electrification_system\n\nTo prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typical... |
572f591404bcaa1900d76889 | What nowdays electrification systems can use? | DC motors which directly use the DC or they may be 3-phase AC motors | [
"Railway_electrification_system\n\nModern electrification systems take AC energy from a power grid which is delivered to a locomotive and converted to a DC voltage to be used by traction motors. These motors may either be DC motors which directly use the DC or they may be 3-phase AC motors which require further con... |
572f591404bcaa1900d7688a | What is the main action AC and DC systems have to deal with? | converting and transporting | [
"Railway_electrification_system\n\nModern electrification systems take AC energy from a power grid which is delivered to a locomotive and converted to a DC voltage to be used by traction motors. These motors may either be DC motors which directly use the DC or they may be 3-phase AC motors which require further con... |
572f591404bcaa1900d7688b | What type of losses happen during conversion and transmission in wires and electronics? | ohmic losses | [
"Railway_electrification_system\n\nModern electrification systems take AC energy from a power grid which is delivered to a locomotive and converted to a DC voltage to be used by traction motors. These motors may either be DC motors which directly use the DC or they may be 3-phase AC motors which require further con... |
572f591404bcaa1900d7688c | What kind of losses take place in transformers and inductors during conversion/transmission process? | magnetic field losses | [
"Railway_electrification_system\n\nModern electrification systems take AC energy from a power grid which is delivered to a locomotive and converted to a DC voltage to be used by traction motors. These motors may either be DC motors which directly use the DC or they may be 3-phase AC motors which require further con... |
572f5a7c947a6a140053c8ac | What two systems were compare in the Soviet Union in 1970? | 3 kV DC and 25 kV AC (50 Hz | [
"Railway_electrification_system\n\nIn the Soviet Union, in the 1970s, a comparison was made between systems electrified at 3 kV DC and 25 kV AC (50 Hz). The results showed that percentage losses in the overhead wires (catenary and contact wires) was over 3 times greater for 3 kV DC than for 25 kV AC. But when the c... |
572f5a7c947a6a140053c8ad | Which system had higher losses in overhead wires? | 3 kV DC | [
"Railway_electrification_system\n\nIn the Soviet Union, in the 1970s, a comparison was made between systems electrified at 3 kV DC and 25 kV AC (50 Hz). The results showed that percentage losses in the overhead wires (catenary and contact wires) was over 3 times greater for 3 kV DC than for 25 kV AC. But when the c... |
572f5a7c947a6a140053c8ae | Which system was used in Soviet Union after all calculations? | 3 kV DC | [
"Railway_electrification_system\n\nIn the Soviet Union, in the 1970s, a comparison was made between systems electrified at 3 kV DC and 25 kV AC (50 Hz). The results showed that percentage losses in the overhead wires (catenary and contact wires) was over 3 times greater for 3 kV DC than for 25 kV AC. But when the c... |
572f5a7c947a6a140053c8af | What came with lesser lesser cost mobile conversion hardware or stationary hardware? | stationary hardware | [
"Railway_electrification_system\n\nIn the Soviet Union, in the 1970s, a comparison was made between systems electrified at 3 kV DC and 25 kV AC (50 Hz). The results showed that percentage losses in the overhead wires (catenary and contact wires) was over 3 times greater for 3 kV DC than for 25 kV AC. But when the c... |
572f5bb3b2c2fd140056807b | What can be seen in the newly electrified lines? | "sparks effect" | [
"Railway_electrification_system\n\nNewly electrified lines often show a \"sparks effect\", whereby electrification in passenger rail systems leads to significant jumps in patronage / revenue. The reasons may include electric trains being seen as more modern and attractive to ride, faster and smoother service, and t... |
572f5bb3b2c2fd140056807c | What can electrification of modern trains effect? | patronage / revenue | [
"Railway_electrification_system\n\nNewly electrified lines often show a \"sparks effect\", whereby electrification in passenger rail systems leads to significant jumps in patronage / revenue. The reasons may include electric trains being seen as more modern and attractive to ride, faster and smoother service, and t... |
572f5bb3b2c2fd140056807d | How can better service quality be achieved? | rolling stock overhaul / replacement | [
"Railway_electrification_system\n\nNewly electrified lines often show a \"sparks effect\", whereby electrification in passenger rail systems leads to significant jumps in patronage / revenue. The reasons may include electric trains being seen as more modern and attractive to ride, faster and smoother service, and t... |
572f618b04bcaa1900d768a3 | What is a major factor whn it comes to electrification? | Network effects | [
"Railway_electrification_system\n\nNetwork effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of the through traffic to non-electrified lines. If through traffic is to h... |
572f618b04bcaa1900d768a4 | What was the reason some electrifications were removed after a while? | through traffic to non-electrified lines | [
"Railway_electrification_system\n\nNetwork effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of the through traffic to non-electrified lines. If through traffic is to h... |
572f618b04bcaa1900d768a5 | Where can the issue of through traffic benefits occur? | long distance trips | [
"Railway_electrification_system\n\nNetwork effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of the through traffic to non-electrified lines. If through traffic is to h... |
572f618b04bcaa1900d768a6 | What can be a drawback of electrification of long distance freight trains? | electrification to isolated areas | [
"Railway_electrification_system\n\nNetwork effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of the through traffic to non-electrified lines. If through traffic is to h... |
572f618b04bcaa1900d768a7 | What does the increasing demand for container traffic make companies use more often? | diesel trains | [
"Railway_electrification_system\n\nNetwork effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of the through traffic to non-electrified lines. If through traffic is to h... |
572f63e6b2c2fd14005680a7 | What is the other issue that comes to sight when using electrification system? | connections between different electrical services | [
"Railway_electrification_system\n\nAdditionally, there are issues of connections between different electrical services, particularly connecting intercity lines with sections electrified for commuter traffic, but also between commuter lines built to different standards. This can cause electrification of certain conn... |
572f63e6b2c2fd14005680a8 | Why the commuter lines built to different standards can cause be complicated? | the implications on the sections it is connecting | [
"Railway_electrification_system\n\nAdditionally, there are issues of connections between different electrical services, particularly connecting intercity lines with sections electrified for commuter traffic, but also between commuter lines built to different standards. This can cause electrification of certain conn... |
572f63e6b2c2fd14005680a9 | What is the solution many lines came up with in order to avoid replacing present rolling stock? | to be overlaid with multiple electrification standards | [
"Railway_electrification_system\n\nAdditionally, there are issues of connections between different electrical services, particularly connecting intercity lines with sections electrified for commuter traffic, but also between commuter lines built to different standards. This can cause electrification of certain conn... |
572f63e6b2c2fd14005680aa | Why are disel trains still used on electrified routes? | due to incompatibility of electrification standards | [
"Railway_electrification_system\n\nAdditionally, there are issues of connections between different electrical services, particularly connecting intercity lines with sections electrified for commuter traffic, but also between commuter lines built to different standards. This can cause electrification of certain conn... |
572f65c704bcaa1900d768d3 | Which of two can be more efficiently electricified? | Central station | [
"Railway_electrification_system\n\nCentral station electricity can often be generated with higher efficiency than a mobile engine/generator. While the efficiency of power plant generation and diesel locomotive generation are roughly the same in the nominal regime, diesel motors decrease in efficiency in non-nominal... |
572f65c704bcaa1900d768d4 | How can electric power plant become more power efficient? | it will shut down its least efficient generators | [
"Railway_electrification_system\n\nCentral station electricity can often be generated with higher efficiency than a mobile engine/generator. While the efficiency of power plant generation and diesel locomotive generation are roughly the same in the nominal regime, diesel motors decrease in efficiency in non-nominal... |
572f65c704bcaa1900d768d5 | How can electric train be more energy efficient? | by regenerative braking | [
"Railway_electrification_system\n\nCentral station electricity can often be generated with higher efficiency than a mobile engine/generator. While the efficiency of power plant generation and diesel locomotive generation are roughly the same in the nominal regime, diesel motors decrease in efficiency in non-nominal... |
572f65c704bcaa1900d768d6 | Which type of train continues to use energy while coasting or being stopped? | diesel | [
"Railway_electrification_system\n\nCentral station electricity can often be generated with higher efficiency than a mobile engine/generator. While the efficiency of power plant generation and diesel locomotive generation are roughly the same in the nominal regime, diesel motors decrease in efficiency in non-nominal... |
572f65c704bcaa1900d768d7 | What causes electric trains to waste energy? | cooling blowers | [
"Railway_electrification_system\n\nCentral station electricity can often be generated with higher efficiency than a mobile engine/generator. While the efficiency of power plant generation and diesel locomotive generation are roughly the same in the nominal regime, diesel motors decrease in efficiency in non-nominal... |
572f688cb2c2fd14005680e5 | Can renewable source of electricity be used in mobile power plants? | unsuitable | [
"Railway_electrification_system\n\nEnergy sources unsuitable for mobile power plants, such as nuclear power, renewable hydroelectricity, or wind power can be used. According to widely accepted global energy reserve statistics, the reserves of liquid fuel are much less than gas and coal (at 42, 167 and 416 years res... |
572f688cb2c2fd14005680e6 | What type of natural resources is more scarce? | liquid fuel | [
"Railway_electrification_system\n\nEnergy sources unsuitable for mobile power plants, such as nuclear power, renewable hydroelectricity, or wind power can be used. According to widely accepted global energy reserve statistics, the reserves of liquid fuel are much less than gas and coal (at 42, 167 and 416 years res... |
572f688cb2c2fd14005680e7 | What is the recent incentive in order to overcome oil scarcity? | to substitute other fuels | [
"Railway_electrification_system\n\nEnergy sources unsuitable for mobile power plants, such as nuclear power, renewable hydroelectricity, or wind power can be used. According to widely accepted global energy reserve statistics, the reserves of liquid fuel are much less than gas and coal (at 42, 167 and 416 years res... |
572f688cb2c2fd14005680e8 | What research can be used in the future if translated? | Soviet studies from the 1980s | [
"Railway_electrification_system\n\nEnergy sources unsuitable for mobile power plants, such as nuclear power, renewable hydroelectricity, or wind power can be used. According to widely accepted global energy reserve statistics, the reserves of liquid fuel are much less than gas and coal (at 42, 167 and 416 years res... |
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