Tokyo Metro 7000 series

The Tokyo Metro 7000 series is a Japanese city commuter electric multiple unit operated by the Teito Rapid Transit Authority and its successor Tokyo Metro from October 1974 to April 2022.
==History==
The 7000 series was conceived in 1974 as a train that would allow for easy maintenance, have the latest technology and have a long lifespan, in addition to being the first sets to operate on the then-soon-to-be-opened TRTA Yūrakuchō Line.
The first set, three-car set 7101, was delivered some time in 1974 and entered service in October 1974; more sets were later built and put into service progressively. When the TRTA was dissolved in 2004, ownership of the sets was handed over to Tokyo Metro. In addition to being used on the Tokyo Metro Yūrakuchō and Fukutoshin lines, the sets are also used for through-running through to and from the Tobu Tōjō Line, Seibu Yūrakuchō and Ikebukuro Lines and the Minatomirai Line.
With the introduction of the 10000 series sets in 2006, the age of the 7000 series sets began to show. Starting in 2010, a total of four set, 7117, 7121, 7122 and 7123, were transferred to the KRL Jabodetabek in Indonesia; three of those sets remain in service while 7121 is no longer in operation having been scrapped in late 2013 due to accident damage.
The last sets were retired on the Tokyo Metro system by April 2022, being replaced by 17000 series sets.
As on 2023, both 7122 and 7123 are now bearing the latest KAI Commuter gray-red-white livery.
==Design==
The 7000 series use a fairly modern design for the time with an unpainted body made of an extruded aluminum alloy. The design of the sets is extremely similar to what is seen on the Tokyo Metro 6000 series sets.
==Specifications==
Construction is of an extruded aluminum alloy. End cars are 20 meters long, 2.8 meters wide and 4.145 meters high. The sets originally used a thyristor-chopper control system, with Mitsubishi and Hitachi providing the thyristor chopper systems; those produced a low drone when the train accelerated from idle. 
Starting in the 2000s, most older sets received "Type B" refurbishment; improvements included the addition of automatic station broadcasting systems, addition of wheelchair spaces and the changing of the roller blind-type destination indicators to three-color LED indicators among other improvements. Another notable improvement was the changing of the chopper control systems to variable frequency drives; the drives were manufactured by Mitsubishi or Hitachi in two- or three-level formats. All variable frequency drives supplied were insulated gate bipolar transistor-based drives.
Two-level Hitachi drives at 165 kW produce a loud screeching noise, two-level Hitachi drives at 160 kW produce a subdued wailing noise, two-level Mitsubishi drives at 165 kW voltage produce a loud hissing sound and two-level Mitsubishi drives at 160 kW voltage produce a sharp hissing sound. The sets also had three-level drives, but those appear to have been removed; three-level Mitsubishi drives produce a unique cadence while three-level Hitachi drives produce a melodic sound.
Newer sets received "Type C" refurbishment which was much smaller in scale, where work was done mainly to paintwork and interior work and modifications to body construction.
== Export ==
The following 7000 series sets have been exported to Indonesia:
* 7017/7117 (stored in Depok depot)
* 7021/7121 (no longer in operation due to colliding with Pertamina fuel truck)
* 7022/7122
* 7023/7123
Both 7022/7122 and 7023/7123 are now bearing the KAI Commuter gray-red-white livery, and both of these are the only Tokyo Metro 7000 series sets to bear the latest KAI Commuter Livery.
== Incidents ==
On 9 December 2013, 7021/7121 was involved in an accident in Bintaro, South Tangerang, where it collided with a Pertamina fuel truck at a railroad crossing on the Rangkasbitung Line, causing 7 deaths, 45 injuries and the destruction of the fuel truck and the front two cars of the set. 7021/7121 was then taken out of service and scrapped in December 2014.
== References ==
*Wikipedia.org
Category:Electric trainsets
Category:Tokyo Metro trains
Category:TRTA trains
Category:Kawasaki locomotives
Category:Kinki Sharyo locomotives
Category:Nippon Sharyo locomotives
Category:Tokyu Car locomotives
Category:Indonesian Railway
Category:Indonesia