[2] In 1955, the Deutsche Reichsbahn was able to resume electric train operations after locomotives and equipment, which had to be handed over to the Soviet Union as reparations after the end of the war, were bought back.

Due to the constantly increasing train loads, the latter often required uneconomical pre-tensioning power, especially as the multiple control system, with which only a small number of the locomotives had been supplied anyway, was removed again as early as the mid-1970s.

[6][7] There were also plans to replace the class 251 locomotives on the Rübelandbahn, which was electrified with 25 kV at 50 Hz, with more modern successors.

There were also plans to electrify the approach line from Halle and to convert electric operation on the Rübelandbahn to the usual 15 kV at 16.7 Hz.

In addition, talks between the GDR and the Federal Republic of Germany began in 1987 with the aim of significantly accelerating rail transit traffic between the FRG and West Berlin, with the electrification and upgrading of the Berlin-Hanover line for speeds of up to 160 km/h being planned.

[2][9] After a specification sheet for the new series had been drawn up, the DR initially ordered four prototypes from VEB Lokomotivbau Elektrotechnische Werke, which were manufactured at the Hennigsdorf plant (near Berlin).

[14] At this time, the Deutsche Bundesbahn had already gained experience with series-built three-phase locomotives with the 120 series, which were considered to be significantly more economical and whose brushless traction motors offered clear maintenance advantages.

As there was an increased demand for passenger locomotives with a top speed of 160 km/h, the decision was made in favour of series production of the class 112.

The prototypes were renumbered class 156 on January 1, 1992 in accordance with the new DB locomotive classification scheme, while retaining their serial numbers.

For example, the locomotives of this class were regularly used in front of an express train to Nauen for a certain period of time and thus even reached the Berlin area.

Circulation plans of the class 156 from 1993 show not only services in front of freight trains with the destinations Chemnitz-Hilbersdorf, Reichenbach (Vogtl.

[20] Although planned for December, the locomotives were already parked on October 18, 2002 and stored in the Dresden-Friedrichstadt freight yard in a preserved state.

[8] The locomotives were sold to Mitteldeutsche Eisenbahn GmbH (MEG) after a year of storage, and removed from Deutsche Bahn's fleet on September 5, 2003.

[22] The reason for the withdrawal of the four locomotives from DB Cargo is said to have been problems with the allocation of personnel, as only a few drivers had been trained for the class 156.

Since January 31, 2007, the class 156 locomotives have been regularly used to haul an intermodal service from Guben to Neuss in the Ruhr region.

In the spring of 2007, test runs took place at MEG, during which the 804 was used in front of freight trains together with the 185 090 locomotive rented from DB.

[11] The locomotives run on two three-axle bogies with a frame of welded steel construction, which largely correspond to those of the 250/155 series.

Tests were carried out in the wind tunnel at the Technical University of Dresden to determine the optimum head shape.

There are also two manually operated TES8F3 roof-mounted disconnectors and a DAT 4a type air circuit breaker with a breaking capacity of 300 MVA.

The primary and secondary windings are split and each feed three traction motor circuits in order to limit the short-circuit currents.

Special windings serve the systems for auxiliary operation and brake excitation as well as for the electric train heating.

The design allows an almost infinitely variable setting of the traction motor voltage and consequently the tractive force, which leads to a high utilization of the coefficient of friction between wheel and rail.

In the 252 series, the traction circuit is designed as a parallel connection of three 16.7 Hz single-phase series-wound motors on the two secondary windings of the power transformer.

This consists of a 380-volt/16.7-Hertz single-phase asynchronous motor with capacitor auxiliary phase and 380-volt/50-Hertz three-phase synchronous generator and is arranged vertically in the engine room.

As with the 112/243 series, the 252 001 and 002 have wired-programmed LEW control electronics based on highly integrated LSL circuit technology.

Plug-in cards serve as the basis for the circuits and components, which are arranged according to their functional relationship and are located in an EGS swivel frame in the driver's cab rear wall 1.

[30] Designed as a heavy freight locomotive, the class 252 is capable of hauling high train masses.

With a homogeneous composition, InterCargo trains can even be hauled at speeds of up to 120 km/h or with a mass of up to 1800 tons without additional tractive power reserve.

Unchanged traffic red, the bright contrasting area between the headlights is strongly reminiscent of the DR livery of the 252 002 and 004.

The control technology of the four prototypes of the 252 series, which in some cases even differed between the locomotives, required considerably more maintenance and the supply of spare parts for defective components was sometimes difficult.