E231 series
| E231 series | |
|---|---|
| A Chūō–Sōbu Line E231-0 series train in December 2022 | |
| Manufacturer | JR East, Kawasaki Heavy Industries, Tokyu Car Corporation | 
| Built at | Niitsu, Kobe, Yokohama | 
| Replaced | 103 series, 113 series, 115 series, 201 series, 205 series, 301 series | 
| Constructed | 1998–2006 2010–2011 (SaHa E231-600 & SaHa E231-4600 carriages) | 
| Entered service | 13 March 2000 | 
| Refurbished | 2014– | 
| Scrapped | 2010– | 
| Number built | 2,736 vehicles | 
| Number in service | 2,476 vehicles (+48 vehicles converted to E235 series) | 
| Number scrapped | 212 vehicles | 
| Successor | E235 series (Yamanote Line) | 
| Formation | 4/5/8/10 cars per trainset (Previously also 11) | 
| Operators | JR East | 
| Depots | Kawagoe, Keiyō, Kōzu, Matsudo, Mitaka, Oyama | 
| Lines served | (See below) | 
| Specifications | |
| Car body construction | Stainless steel | 
| Car length | 20,000 mm (65 ft 7 in) | 
| Width | 2,950 mm (9 ft 8 in) | 
| Doors | 4 pairs per side (previously also 6 pairs per side) 2 doors per side (Green cars) | 
| Maximum speed | 120 km/h (75 mph) | 
| Traction system | IGBT-VVVF | 
| Acceleration | 2.5, 3, or 3.3 km/(h⋅s) (1.6, 1.9, or 2.1 mph/s) | 
| Deceleration | 4 km/(h⋅s) (2.5 mph/s) (service) 4.5 km/(h⋅s) (2.8 mph/s) (emergency) | 
| HVAC | AU725/AU726 | 
| Electric system(s) | 1,500 V DC overhead | 
| Current collector(s) | Overhead line | 
| Bogies | DT61 (powered), TR246 (trailer) | 
| Braking system(s) | Regenerative brake, electronically controlled pneumatic brakes | 
| Safety system(s) | ATS-P, ATS-SN, D-ATC | 
| Coupling system | Shibata type | 
| Multiple working | E233-3000 series (for E231-1000 series only) | 
| Track gauge | 1,067 mm (3 ft 6 in) | 
The E231 series (E231系, E231-kei) is an electric multiple unit (EMU) train type used for commuter and outer-suburban services operated by East Japan Railway Company (JR East) in Japan since 2000.