In 1927 and 1928, Wegmann built six electric motor cars along with three cab cars for use between Leipzig and Halle. The electric part came from SSW. They were intended for express and stopping services as a more economical replacement for loco-hauled trains. Each motor car had two 285 kW traction motors, one on the inside axle of both bogies. 

In addition to the motor and cab cars, six two-axle passenger cars were ordered with a matching livery. It quickly became evident that a train combined of a motor and a cab car was underpowered. Not to mention that the power was not enough if a trailer was added to this combination. This could only be improved by combining two motor cars with a cab car or a maximum of two trailers.

The motor cars originally carried the consecutive numbers ET 501 to ET 506 and were renumbered twice before becoming class ET 41 in 1940. The cab cars were designated ES 41. After World War II, only one motor and one cab car were surviving. Both were passed to the USSR in 1946 and never returned.