August 29, 1929 - start of operation electrified lines Russia Moscow - Mytishchi
The electrification of the suburban area started talking in 1924 due to the strongly increased passenger traffic.
In September 1924 the management of North Road created Electrification Bureau, which has developed a preliminary design of the electrification of traffic on the route Moscow - Pushkin and Mytischi - Schyolkovo. As the power supply system has adopted a system of direct current with rated voltage 1500V is then used on other sites with multiple unit traction.
DC system was chosen because the single-phase current required would be more difficult and expensive motor cars because of the need for setting these transformers. In addition, the traction motors are DC ceteris paribus higher torque and better able to start in comparison with single-phase AC motors. This is especially important for motor cars running on suburban areas with a large number of stops, where high acceleration when starting off.
Voltage of 1500 V was chosen due to the fact that it takes much less copper catenary system compared to 600-800 V. At the same time it became possible to create a reliable electric motor car, to which it was impossible at that time to count at a voltage of 3000 V.
Electrification of Moscow - Mytishchi began in 1927. The motion was served trehvagonnymi section, consisting of two motor car and trailer, one of which had a luggage compartment.
Experience the very first years of operation section Moscow - Mytishchi convincingly demonstrated the advantages of electric traction on steam and helped expand the network of electric railways. In addition to great fuel economy, the introduction of other motorized traction made it possible to significantly reduce the locomotive and rolling stock. Thus, already in the early 30-ies. operated on this line section by 33 railcar carrying capacity of 43 replaced the train and shunting locomotive and about 400 commuter rail cars.