In the 1960s, the main electric trains on the railways of the USSR were ER1, ER2 and ER9. Compared to their predecessors, the compositions of the C series, they had significantly higher technical and economic characteristics. At the same time, the idea of even more efficient use of multiple unit traction in the most loaded sections did not leave the designers and engineers who developed in 1960 the ER10 electric train with an increased body length, the presence of additional entrance doors in the center of the cars and equipment that made it possible to use electric (regenerative-rheostatic) braking. However, the power of the ER10 traction engines was recognized as insufficient, and in 1964 RVZ produced two new four-car sections, which received the ER22 series. In 1965 Due to the large differences from the rest of the series, the ER22-01 electric train was no longer in operation, but was used for testing and fine-tuning experimental electrical equipment. In 1967, RVZ started serial production of ER22 electric trains, which continued until 1968 More detailed installation in the Readme