The class 209 EMU, introduced in 1992, was the first one of the “new series trains” generation, also called “Shin-keiretsu densha”. They are being powered by three-phase AC traction motors and controlled by GTO or IGBT converters. The class 209 in specific was designed for suburban service in the Tokyo area as a replacement for the class 103. With a low unit cost, they were built for a short service life of only 15 years.
The sets are usually composed of two, four, six, eight or ten cars. Depending on the requirements of each line, between 40 and 67 percent of the cars are being powered by four 95 kW traction motors. As planned, the oldest sets were already scrapped in 2007, but others are still running. The direct successor of the 209 is the E231. 