The Grand Duchy of Baden State Railways used the IV f from 1907 on its 413 km long main line from Mannheim to Constance. However, this was unable to cope with long, fast routes with its driving wheels, which were only 1,800 mm large. Thus, in 1915, the IV h was ordered from Maffei in Munich, where the IV f and the S 3/6 had already been manufactured. Since only use on flat routes was planned, the IV h received driving wheels with a diameter of 2,100 mm. This negatively affected acceleration, but made it possible to maintain high speeds for a long time. The certification was only for 110 km/h, which was 10 km/h faster than its predecessor series. It was only in the thirties that it proved on test drives at speeds of up to 155 km/h that it ran very smoothly even at higher speeds. It was therefore equipped with more powerful brakes and approved for 140 km/h.
The locomotive was powered by a four-cylinder compound engine, which combined characteristics of the De Glehn and Von Borries types. The low-pressure cylinders drove the second coupled wheel set and had to be located on the outside due to their large diameter. While the outer high-pressure cylinders on the De Glehn type were pulled back to achieve shorter connecting rods, the outer cylinders were at the height of the smoke chamber. Thus, the high-pressure cylinders were on the inside and drove the first set of coupled wheels. Since they were also pulled very far forward, they could be clearly seen from the outside.
When they were taken over by the Reichsbahn, they became the class 183. After about ten years of service on the Baden trunk line, the 20 built IV h were replaced by class 01 standard locomotives and relocated to other locations. Although they had a higher fuel consumption than the newer locomotives, it later turned out that they could almost keep up with the 01 and even surpassed the 03 in terms of power. After all, the power measurements were in a range from 1,950 to 2,200 hp.
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Die Lokomotive, August 1925
After the war, all 19 remaining examples went to the Bundesbahn and only road number 18 314 ended up being traded for an S 3/6 to the Reichsbahn, where it was fundamentally rebuilt. All others were initially retired because their Number was very small. However, three were subsequently reactivated and modernized for use as brake locomotives or for other trials. The 18 316 was preserved and was again in running condition between 1995 and 2002, but was parked again after damage.