After the Second World War, as a first step the Bundesbahn began restoring the overhead lines in southern Germany. Initially, the existing pre-war electric locomotives and a few newly built examples of these were sufficient. However, since there were extensive plans to electrify many lines throughout Germany, a large number of new electric locomotives had to be built immediately. In a similar manner to the standard steam locomotives of the 1920s and 1930s, many standardized parts were to be used in different locomotives, from which the term “standard electric locomotives” arose. They were to be operated from a seated position, which, since the introduction of the dead-man's switch, no longer caused problems with the driver's attention.
Originally only two types of locomotives were planned for all purposes. The first type was a four-axle locomotive with a maximum speed of 125 km/h, which was intended to be used for all types of passenger trains and light freight trains and could therefore be assigned to a similar area of application as the E 44. In addition, a six-axle locomotive for heavy freight trains was to be developed, which could serve the same tasks as the E 94. Since it was not possible to simultaneously optimize a single locomotive type for hauling express trains and medium freight trains using single-phase AC motors, the range of locomotive types had to be expanded.
The result was the first generation of standard electric locomotives with the E 10 express locomotive, the E 40 freight locomotive, the lighter E 41 for commuter trains and the six-axle E 50. The even faster E 01 was not implemented because the rail network was not designed for higher speeds. The power was transmitted via the so-called “Gummiringfederantrieb” (rubber ring spring drive), which had been developed by SSW. In principle, this was a nose-suspended motor that was additionally cushioned by a hollow shaft with rubber elements.
Almost 2,000 locomotives of this generation were made, many of which were still in use after the turn of the millennium and are considered to be extremely robust and reliable. The direct successors of the E 10 and E 50 were introduced with the classes 111 and 151 in the 1970s. The fast-running class 103 and the multi-system locomotive of the class 181 were developed with major deviations from the standard locomotives.
With the progressive development of semiconductor technology, it was possible for the first time in the 1970s to implement practical options for controlling three-phase traction motors. This soon became necessary because the traction motors previously used in rail vehicles had a sharply falling torque curve as the speed increased. For this reason, the gear ratio between the traction motor and the wheelset had to be selected depending on the application in such a way that either sufficient traction or a high speed could be attained. With three-phase asynchronous motors, there is a significantly more favorable torque curve, with which a single locomotive is suitable for a broader range of applications. With three-phase motors and the corresponding control electronics, some industrial locomotives from Henschel first appeared in the 1970s, before the class 120 was introduced in the 1980s as a 200 km/h universal locomotive that was equally suitable for freight trains.
The electric locomotives of the Bundesbahn were also an indispensable mainstay in the nineties after the foundation of the DB AG. They initially had competition in the form of the electric locomotives of the former East German Reichsbahn, which were also to be used in West Germany. Since the large-scale electrification of the Reichsbahn only started much later, the members of the former classes 243 and 250, which were available in large numbers, were more up to date than the standard locomotives of the Bundesbahn. While the 243 replaced many older E 10 and E 41 in commuter traffic, the E 50 and class 151 faced competition from the 250. In the second half of the 1990s, the modern generation of three-phase locomotives finally came along, and as their number increased, more and more Bundesbahn electric locomotives became surplus. After their career in the DB AG, the models suitable for freight trains in particular could still be sold to private companies, which, despite their age, still use them every day.