Keio 5000 series (2017)
The Keio 5000 series is an electric multiple unit commuter train type operated by the private railway operator Keio Corporation in the Tokyo area of Japan since 29 September 2017. A total of five ten-car trainsets were built by J-TREC. The trains feature rotating seats that can be arranged longitudinally for daytime services and in forward-facing transverse pairs for reserved-seat Keio Liner commuter services in the evenings which started on 22 February 2018.
Design
The fleet of five ten-car 5000 series trainsets was built by Japan Transport Engineering Company at a total cost of approximately JPY10 billion. A sixth set was delivered in December 2019.Formation
The ten-car trains are formed as follows, with six motored cars and four non-powered trailer cars, and car 10 at the Shinjuku end.| Car No. | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Numbering | Tc2 | M2 | M1 | T2 | M2' | M1' | T1 | M2 | M1 | Tc1 |
| Numbering | 578x | 528x | 523x | 558x | 518x | 513x | 553x | 508x | 503x | 573x |
| Weight | 29.8 | 35.6 | 36.3 | 26.7 | 34.0 | 35.4 | 26.8 | 35.8 | 36.3 | 30.2 |
| Capacity longitudinal config. | 119/39 | 130/45 | 130/45 | 130/45 | 130/45 | 130/45 | 130/45 | 130/45 | 130/45 | 119/39 |
| Capacity transverse config. | 115/39 | 126/45 | 126/45 | 126/45 | 126/45 | 126/45 | 126/45 | 126/45 | 126/45 | 115/39 |
Cars 2, 3, 6, 8, and 9 each have one single-arm pantograph.
Interior
Passenger accommodation consists of rotating pairs of seats that can be arranged in longitudinal configuration for regular daytime services or in transverse forward-facing configuration for reserved-seat evening commuter services from in Tokyo to and. LED lighting is used in the interiors, and pairs of LCD passenger information screens are provided both above the doorways and suspended from the ceilings. Free WiFi and AC power sockets are provided. Space for wheelchairs and pushchairs are provided in each car.History
Details of the new trains were officially announced in March 2016. Between April and May 2017, Keio held a public poll to choose the brand name for the new reserved-seat services starting in spring 2018. The name Keio Liner was announced on 24 January 2018, chosen from the following five candidates.- Keio Liner
- Keio Smart Liner
- Keio Prime Liner
- Luxpress
- Westar
Reserved-seat Keio Liner services from Shinjuku Station commenced on 22 February 2018. Inbound Keio Liner trains to Shinjuku will begin on 22 February 2019.
The order of a sixth set was announced in April 2019. The set was delivered in December 2019.
Build histories
The manufacturers and delivery dates for the fleet are as shown below.| Set No. | Manufacturer | Date delivered |
| 5731 | J-TREC | 30 June 2017 |
| 5732 | J-TREC | 15 September 2017 |
| 5733 | J-TREC | 2017 |
| 5734 | J-TREC | |
| 5735 | J-TREC | |
| 5736 | J-TREC | December 2019 |