The FS Class E.471 locomotives were prototype three-phase AC

electric locomotive An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or on-board energy storage such as a battery or a supercapacitor. Locomotives with on-board fuelled prime movers, such as diesel engines or g ...

s designed for the

Italian State Railways Ferrovie dello Stato Italiane S.p.A. ( "Italian Railways of the State"; previously only Ferrovie dello Stato, hence the abbreviation FS) is Italy's national state-owned railway holding company that manages transport, infrastructure, real estat ...

(FS). They constituted the first Italian experiment in using a

phase converter A phase converter is a device that converts electric power provided as single phase to multiple phase or vice versa. The majority of phase converters are used to produce three-phase electric power from a single-phase source, thus allowing the ope ...

. The final goal was to power them with

single-phase In electrical engineering, single-phase electric power (abbreviated 1φ) is the distribution of alternating current electric power using a system in which all the voltages of the supply vary in unison. Single-phase distribution is used when load ...

alternating current Alternating current (AC) is an electric current which periodically reverses direction and changes its magnitude continuously with time in contrast to direct current (DC) which flows only in one direction. Alternating current is the form in whic ...

, constituting the first case of a European locomotive of this type designed according to modern criteria. However, the difficulty of the development, and political interference, led to the abandonment of the project.

History

In 1928, following the experience acquired in the three-phase high-voltage (10 kV) AC operation with FS Class E.470, a new locomotive of was built, which was supposed to represent the ultimate development of three-phase traction. It was called E.471, and it had the same 1′D1′ wheel arrangement as E.470, but it was technically different. Designed by the famous engineer

Kálmán Kandó Kálmán Kandó de Egerfarmos et Sztregova (''egerfarmosi és sztregovai Kandó Kálmán''; 10 July 1869 – 13 January 1931) was a Hungarian engineer, the inventor of phase converter and a pioneer in the development of AC electric railway tract ...

and built in the plant of Construzioni Elettro Meccaniche di Saronno ( CEMSA), it was aimed at the future development of three-phase traction. According to the research of the engineer the project was not developed by the FS but autonomously by CEMSA thanks to the collaboration it had established with Kandó. According to some oral testimonies, after management changes at the Material and Traction Service of FS due to the advent of Fascism in Italy, the project was judged "an error of the engineer Donati" and the test results were held to be unsatisfactory. Ten locomotives had been ordered but the project was terminated early and only one was actually built. On the other hand, Mascherpa provided an impressive documentation from which it seems that, at the end of the test runs, a

tractive effort As used in mechanical engineering, the term tractive force can either refer to the total traction a vehicle exerts on a surface, or the amount of the total traction that is parallel to the direction of motion. In railway engineering, the term t ...

corresponding to that envisaged was achieved. Rather, the real reason for the termination was the hostility of the new FS leadership to the engineer Alfredo Donati (former director of the Special Electrification Unit of the General Directorate of FS) who was

deported Deportation is the expulsion of a person or group of people from a place or country. The term ''expulsion'' is often used as a synonym for deportation, though expulsion is more often used in the context of international law, while deportation ...

following the appointment of the extraordinary commissioner . The success of

direct current Direct current (DC) is one-directional flow of electric charge. An electrochemical cell is a prime example of DC power. Direct current may flow through a conductor such as a wire, but can also flow through semiconductors, insulators, or eve ...

experiments, favoured by the new railway management, meant that the E.471 remained at the prototype stage and never entered regular service.

Technical details

These were

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 adv ...

locomotives and the long-term aim was to run them from a

supply. For the tests, they were run from a three-phase supply at either 3.6 kV, 16.7 Hz or 10 kV 45 Hz. Current collection was made by a pair of twin-collector

bow collector A bow collector is one of the three main devices used on tramcars to transfer electric current from the wires above to the tram below. While once very common in continental Europe, it was replaced by the pantograph or the trolley pole, itself o ...

s. Mechanical drive from the two frame-mounted traction motors to the wheels was by means of a Kandó

triangle drive A jackshaft is an intermediate shaft used to transfer power from a powered shaft such as the output shaft of an engine or motor to driven shafts such as the drive axles of a locomotive. As applied to railroad locomotives in the 19th and 20th centu ...

and

coupling rod A coupling rod or side rod connects the driving wheels of a locomotive. Steam locomotives in particular usually have them, but some diesel and electric locomotives, especially older ones and shunters, also have them. The coupling rods transfer t ...

History

Technical details

References

Further reading