In the development of a single-axle drive for electric locomotives, one of the approaches was to use the Buchli drive, as used in Switzerland. The 21 examples of the series initially designated as the Bavarian ES 1 were equipped with it and put into operation by the Reichsbahn as the E 16. They were used by the Bundesbahn until 1980 and were still the only locomotives in Germany with this technical solution. The Buchli drive was characterized by the fact that one traction motor was located above the axle in the locomotive body and its power was transmitted by a one-sided mechanism on the axle. Power was again transmitted between the large gear wheel and the axle via coupling rods. This design is externally recognizable by the cover of the gear wheel. Although the technology was highly complex, the engines could be completely decoupled from the impacts of the ground.

Control was via a new type of linear mechanical tap changer, which had been used shortly before on the E 32. Its further development was later also used in the standard electric locomotives. The chassis of the first five locomotives was designed with two bogies, each consisting of one leading axle and two powered axles. This solution did not work, and so the following locomotives were designed with driving axles in a main frame and Krauss-Helmholtz bogies. The first five were also converted to this form directly afterwards.

The first ten machines were given the Bavarian designation ES 1 when they were delivered in 1926. They had an hourly and continuous output of 2,340 and 2,020 kW and were soon renumbered E 16 01 to 10. Seven more followed in the following year as road numbers E 16 11 to 17. Their output had increased to 2,580 and 2,400 kW respectively. Finally, four more machines were ordered in 1932 with the numbers E 16 18 to 21. Due to technical advances, the output was now 2,944 and 2,655 kW.

Despite their unusual propulsion technology, the locomotives were used for a very long time. Only two were lost in the war, all the rest were taken over by the Federal Railways. There only the E 16 12 had to be retired in 1967 due to an accident, all other 18 locomotives were redesignated in 1968 as class 116. These were retired between 1973 and 1980.

The EP 1, also called EP 3/5, were the first electric locomotives of the Bavarian State Railways for the single-phase alternating current of 15.000 volts and 16 2/3 Hz, which is still in use today. In 1912, five examples were built for the first lines with this current system. The first of these lines was the 56 km long Mittenwaldbahn between Garmisch and Scharnitz, on which electric traffic began just four months after it opened. The following year the Ausserfernbahn from Garmisch to Reutte in Tirol was added, which is 94 km long. Both routes have extremely steep inclines with a maximum gradient of around 3.8 percent.

Maffei had produced the Baden A1 in 1910 in cooperation with SSW. On the basis of this, the EP 3/5 with the wheel arrangement 1-C-1 was developed. A very large series motor was used to power the locomotive, which stood on the locomotive frame and had 28 poles. Due to its low speed, it could drive the driving axles directly via a slanted rod, jackshaft and coupling rod. The power came through an induction regulator. A special feature was the electric train heating, since later electric locomotives still had a steam boiler.

The locomotives were taken over by the Reichsbahn in 1925 and classified as E 62 01 to E 62 05. Since they were well suited for the steep secondary lines with their low speed, they remained in use. After the war, the Bundesbahn took over the three remaining examples. The E 62 001 was the last to be retired in 1955 and later came to the Nuremberg Transport Museum. However, since a devastating fire in the engine shed, only the drive unit remains, as the wooden structure burned down completely.

These light passenger locomotives were ordered in 1922 as EP 2 by the Bavarian Group Administration. Since they were procured between 1924 and 1926, they only wore the Bavarian designation for a short time and were subsequently known only as the E 32. In contrast to other electric locomotives from the 1920s, some of the machines remained in use for a very long time, so that the last examples, now designated as class 132, were not retired until 1972.

What was striking about the E 32 was the short and box-shaped body, which, like many Bavarian machines, had beveled corners and ensured an external length of only about 13 meters. Also typical for passenger locomotives from Bavaria were the gangways at the ends, which were later removed to simplify maintenance. Two twelve-pole AC series-wound motors sat on the frame and were connected to a common reduction gear. According to the state of the art at the time, the power was still transmitted via inclined rods and a jackshaft to the three coupled axles. The ability to negotiate curves was improved by connecting one of the running axles to a coupled axle via a Krauss-Helmholtz bogie. 

In addition to the 19 orders from the Bavarian group administration, ten more came from the Reichsbahn, so that 29 units were finally produced. With a maximum axle load of less than 19 tonnes, the E 32 could be used on all electrified routes in Upper Bavaria. Due to the good running characteristics, the gear ratio was changed in 1936 on eight machines so that they could run 90 instead of 75 km/h. These were now referred to as E 32¹. At the end of the war, a total of five machines were lost and all the rest were still in use in Upper Bavaria, so that these 24 units were all taken over by the Bundesbahn. With the exception of two, all the others were still present when the 1968 renumering was carried out. The last eight were retired on August 1, 1972. Road number 132 027 is still in existence today, it carries the old number E 32 27 again.

For the line from Salzburg via Freilassing to Berchtesgaden, which was electrified in 1914, eight passenger locomotives were built, of which four each received the electrical equipment from SSW and MSW. The former were designated as EP 3, the others as EP 4. Since both variants had the wheel arrangement 1-C-2, they were also known as EP 3/6 because three of a total of six axles were powered.

In terms of construction, the locomotives had a similar structure to that found on many electric passenger locomotives at the time. The asymmetrical arrangement of the running gear and the machinery was due to the fact that the train was heated by a boiler that was above the single carrying axis and could be recognized by a chimney. The transformer stood on the bogie. According to the state of the art at that time, the power was provided by a single large motor with 20 poles, which was located in the middle of the locomotive on the frame. It transmitted its power to a jackshaft via sloping connecting rods and further to the three driven axles via coupling rods. With an hourly and continuous output of 690 and 480 kW, respectively, it allowed a top speed of 80 km/h.

Since the main route of the locomotives was very winding, special attention was paid to the optimal chassis design. Thus, the single carrying axle was connected via a Krauss-Helmholtz bogie and the bogie via a Krauss-Lotter bogie with the respective adjacent coupled axle. Since all axles except one were mounted with lateral play, there was no fixed wheelbase and it was therefore possible to run through tight corners without bumps or a tendency to sway.

After the boilers had been removed for further use in hospital trains during the First World War, the trains ran in cold weather with an additional small tank locomotive, which was converted into a heating locomotive. All four EP 3 were taken over by the Reichsbahn and given the numbers E 36 01 to E 36 04. They continued to be used almost exclusively in front of passenger trains and were relocated from the main line to one of the branch lines towards the end of their service life. Their career as a locomotive ended between 1941 and 1943 with the retirement or the removal from the maintenance schedule. Two pieces got a second life after they were converted into non-powered Klima snow plows and continued to be used until around 1980.

The E 79 series comprised only two locomotives that were ordered by the Bavarian Reichsbahn group administration in 1923 to cope with the increased freight train weights on the Freilassing-Berchtesgaden route. Due to technical problems during development and production, they were not delivered until 1927 and were given the new Reichsbahn designation instead of the Bavarian designation EG 4. The body construction part came from Maffei in Munich and the electrical equipment was developed by Pöge Electricity AG in Chemnitz.

In order to be able to master the up to four percent steep inclines, the design envisaged heavy loomotives with a 1-C-1 wheel arrangement. However, since the necessary electrical equipment turned out to be significantly heavier than originally thought, the design was changed to the 2-D-1 wheel arrangement. Despite the two additional axles, the axle load reached almost 20 tonnes. The bogie was connected to the first coupled axle with a Krauss-Lotter bogie and the trailing axle was guided in a Bissel truck. Power was provided by two high-speed electric motors whose speed was reduced by a common reduction gear. This in turn transferred the power to two jackshafts, which finally drove the four axles with 1,250 mm wheels via coupling rods. 

In addition to freight trains, the two locomotives were also used to pull passenger trains, whereby the low power compared to other modern electric locomotives was noticeable. However, since they still had an adhesive weight of almost 80 tonnes, they were increasingly used as pusher locomotives on the steep and winding route. In the years that followed, the two machines were not really convincing in operation. In addition to the small number of locomotives, the procurement of spare parts was made more difficult by the fact that Pöge was not one of the typical companies that supplied assemblies for Reichsbahn locomotives. In addition, one of the two locomotives stood out in particular with excessively frequent defects. After delivery of the considerably lighter and nevertheless more powerful E 44, the two E 79s could be dispensed with and they were retired in 1941 and 1942 respectively.

With the numbers 1 to 5, the LAG procured a series of five electric locomotives between 1905 and 1930 for various areas of application. Although they looked very similar on the outside, they had big differences, especially in terms of power. Its historical importance is due to the fact that the LAG 1 was the first locomotive in Germany to be developed for single-phase alternating current. On its main line between Murnau and Oberammergau, a 5 kV and 16 2/3 Hz power system was used, which was only converted to the current system in 1954/55. All engines in this class had two axles, each driven by a nose-suspended motor. The cab was in the middle to allow good visibility in both directions. On either side was a box-like hood, the top sloping towards the ends. In addition to a number, they were given women's names (in the order 1 to 5) Katharina, Pauline, Hermine, Johanna and Adolphine.

The first engine was delivered in 1905 with mechanics and electrics from the Katharinahütte in Rohrbach and SSW and was intended for use in front of freight trains. It had an hourly output of 206 kW, a continuous output of 160 kW and weighed 23.5 tonnes.

Numbers 2 and 3 were almost identical and were delivered by Krauss and SSW in 1909 and 1912. In contrast to number 1, they were built for passenger transport in order to relieve the railcars used. With an hourly and continuous output of 352 and 306 kW, they were significantly more powerful. In 1938 and 1940 they received a modernization of the electrical equipment, which also included the installation of a dead man's switch.

169 005 (formerly No. 5 “Adolphine”) in June 2012 in Koblenz-Lützel

Urmelbeauftragter

The LAG 4 of 1922 was an exception as it initially had a cab at the rear end. It was created from one half of a double locomotive that Siemens had already built in 1902 for high-speed tests with three-phase current. It got new motors, which together delivered an hourly and continuous output of 268 and 237 kW. In 1934, after a transformer fire, it received new machinery that corresponded to those of the other machines.

The last of the five examples was built in 1930 by Maffei and SSW for heavy freight trains. In addition to a beefier appearance with a larger cab and increased overall length, it delivered significantly higher power than its predecessors. The hourly output was now 605 and the continuous output 565 kW.

When the LAG was taken over by the Reichsbahn in 1938, the locomotives were given the designations E 69 01 to E 69 05. When the line was converted to 15 kV in 1954, the four newer engines were also converted for this system. Only road number E 69 01 was retired because it was 49 years old at the time and had clocked up 1.5 million km. The rest were retired between 1977 and 1982 and were at times the oldest electric locomotives in the Bundesbahn. All pieces can still be viewed today. While number 1 is in the Lokwelt Freilassing, number 3 in the DB Museum Koblenz-Lützel and number 4 in front of Murnau station, the other two are still operational. The No. 2 is mostly exhibited in the DB Museum Nuremberg and the No. 5 belongs to the Bavarian Localbahn Association and is used frequently.

The EV 1/2 was built to test electric operation on a circuit track. It was supposed to provide information on wear and tear, partly remotely controlled, in continuous operation 20 hours a day. It was composed of two parts, each with two axles, and only received three nose-suspended traction motors ex works. However, the fourth traction motor was supplied and installed after testing when the locomotive came to the Hamburg Port Railway. In the Reichsbahn it became E 73 03 and was decommissioned in 1932.

These were three electric locomotives with which the Prussian-Hessian State Railways tested the new type of traction for use in front of express trains since 1911. The requirements for the test locomotives were a continuous output of 700 kW and a speed of 100 km/h with a few express cars on the hook. For the purpose of comparability, all three received the chassis and body from Hanomag, while the electrical part of the ES 1, ES 2 and ES 3 came from Siemens-Schuckert, AEG and Bergmann respectively. The wheel arrangement was 2-B-1 and therefore asymmetrical, although the vehicles were bidirectional.

The ES 1 was designed for 110 km/h, but could reach up to 135 km/h with the bogie in front. Although the continuous output did not reach the required 700 kW, it was able to pull a 240-tonne train at a constant speed of 100 km/h. The ES 2 nominally had a slightly lower maximum and continuous power, but was able to achieve a higher tractive effort. Compared to the first two, the ES 3 had a significantly higher power and had a wooden structure, but could not convince due to persistent problems in the electrics.

The test drives with the three locomotives took place on the Dessau-Bitterfeld route, which was one of the first with the 15 kV and 16⅔ Hz power system, which is the most widespread in German-speaking countries today. They continued until the outbreak of World War I in 1914. The ES 2 was the only one of the three locomotives that was able to make it to the Reichsbahn and was in service on the Wehratalbahn for a few years. There it was designated E 00 to illustrate the pioneering role of the Prussians in electric traction.

After the testing of electric locomotives in Central Germany was completed, the Prussian State Railways ordered new machines for different train types. In 1912, ten locomotives with the numbers ES 9 to ES 18 were procured for express trains, which were followed by a further order for the ES 19 in the following year.

In order to be able to guarantee good running characteristics in both directions of travel and at the same time sufficient traction for heavier express trains, the wheel arrangement 1-C-1 was chosen. On the side, which usually formed the front, the carrying axle was connected to the first coupled axle to form a Krauss-Helmholtz bogie. On the other hand, a simpler Adams axle was used for the rear carrying axle. 

The arrangement of the machinery was unusual in that the main transformer was located at the rear of the locomotive, still behind the second driver's cab. The interior of the engine room was occupied by a coal-fired steam boiler in addition to the single traction motor with a stator diameter of 3,200 mm. The latter proved to be not powerful enough to heat the entire train, so it was removed from all locomotives by 1925. The traction motor drove a jackshaft between the second and third coupled axles via an inclined connecting rod under the locomotive body. Despite a driving wheel diameter of only 1,350 mm, speeds of up to 110 km/h were possible, which were accompanied by high engine speeds.

The outbreak of the First World War delayed the delivery of the machines considerably. Since electrical operations in Central Germany had also been discontinued at this time, the locomotives were relocated from the Halle depot to the Nieder Salzbrunn depot in Silesia. There they had to perform services that were above their reasonable load limit. Because of the poorer manufacturing quality and often neglected maintenance during wartime, there were many defects and failures. After the end of the war they came back to Central Germany and were mainly used in front of passenger trains. Ten of the eleven locomotives received the new designation E 01 in 1926, but decommissioning had already begun and the last machine was retired in 1929.