Tuesday, 21 October 2014

The Mito Line: Unique AC-DC Local Route

EMU JR East 415-1500 series travels on the Mito Line
The JR East Mito Line is an east-west trending local route in the northern part of the Tokyo metropolitan area. Connecting Oyama in Tochigi Prefecture and Tomobe in Ibaraki Prefecture, there are 16 stations on the 50.2 km long route. The track is single and its gauge size is 1,067mm.

A unique feature of the Mito Line is its electric system. 1,500V DC overhead is applied in the western section between Oyama and Otabayashi, while 20,000V AC overhead is used in the eastern section between Otabayashi and Tomobe. The reason for applying the AC system in the eastern section is that the direct current has adverse effects on the observation work taking place at the national magnetic observatory located near the track. AC-DC local line is quite unique in Japan.

The trains on the Mito Line, of course, have an AC-DC dual electric system. As I introduced before, the EMU E501 series is an example of such trains. The other AC-DC trains on the Mito Line are the EMU 415-1500 and the E531 series.

The 415-1500 series was launched in 1986. It is a 4-car train, which has bolster-less bogies. The electric control system is an old-fashioned rheostatic with a field weakening mechanism. The E531 series was launched in 2005. It is mainly operated on the Joban Line with a maximum speed of 130 km per hour to reinforce its competitiveness against its adjacent new railway, Tsukuba Express.

The Mito Line is a fascinating unique route for rail-fans.

EMU JR East E531 series travels on the Mito Line