Background and overview
JR Shikoku carried out the electrification extension of the Yosan Line from Kan-onji to Iyo-shi to reinforce transportation services in the Matsuyama area and to provide direct intercity services linking Okayama and Matsuyama. Consequently, in 1990, JR Shikoku developed the 7000 series DC commuter electric multiple unit (EMU) trains required for the newly electrified section of the Yosan Line between Iyo-Hojo and Iyo-shi, which opened in November 1990.
The 7000 series comprises class 7000 powered double-cab cars and class 7100 single-cab trailer cars, designed for operational flexibility.
A total of eight class 7000 units and four class 7100 vehicles were manufactured and delivered to the Matsuyama Depot in 1990.
Car body
The carbody of the 7000 series measures 20,800 mm in length and 2,900 mm in width, with a bogie centre distance of 14,400 mm. The body height is 3,565 mm, as the folded pantograph height must be limited to 3,900 mm in order to remain below the upper structure clearance. This restriction was introduced as a countermeasure for tunnels on the Yosan Line, which have a smaller cross section.
The structure is primarily composed of stainless steel, except for the bolster beams, the end sections of the centre beam, and selected cross beams, which are fabricated from weather-resistant steel plate (Steel Plate Atmospheric, e.g. SPA) or hot-rolled steel plate for general structural applications (e.g. SS300). The exterior features unpainted bead-stiffened stainless panels with a light blue waistline band running the length of each car below the windows.
The gangway-equipped cab end, constructed of steel, incorporates a low-profile
driver's cab designed to accommodate conductor-less operation. Curved windscreens
are used to improve forward visibility. The cab end is painted silver,
with a light blue waistline band and black framing around the windscreens.
A destination roll sign is mounted above the gangway door. Exterior lighting
includes two rectangular sealed-beam headlights positioned on either side
of the gangway and two externally mounted rectangular taillights.
Each side of the vehicle is equipped with two 1,000 mm-wide single-leaf semi-automatic stepped sliding doors at either end of the body and one 1,300 mm-wide double-leaf semi-automatic stepped sliding door at the centre. Door cut-out operation is applied to the centre doors under conductor-less operation. Window arrangements include three 1,080 mm-wide drop windows and one 660 mm-wide drop window adjacent to the centre door between the doors.
Each car is centrally fitted with a roof-mounted S-AU58 air conditioner rated at 33,000 kcal/h. Electric fans within the air conditioner supply fresh air into the passenger saloon, instead of roof-mounted ventilators.
Each car is equipped with automatic jumper couplers at either end to facilitate rush-up operations.
Bogies
The bogies feature bolster-less secondary air suspension, conical multilayer rubber-spring journal supports, and a Watts linkage draw gear.
Power transmission utilizes Twin Disc (TD) flexible joints with carbon-fiber reinforced plastic (CFRP) deflecting plates. The gear ratio is 7.07, optimized for high acceleration performance at medium to high speeds.
The braking configuration varies by bogie type. Powered bogies are equipped with single-tread brake rigging incorporating automatic gap-adjusting mechanisms. Trailer bogies combine a single-disc brake device with single-tread brake rigging to enhance overall braking performance.
Traction unit and ancillary equipment
The traction system, designated S-SC58, employs a two-step variable frequency
drive (VFD) utilizing Gate Turn-Off (GTO) thyristors to control four asynchronous
motors, type S-MT58, each rated at 120 kW per vehicle. This configuration
enables a powered-to-trailer ratio of 1:2, although the actual ratio varies
depending on the train set formation. To ensure constant acceleration performance,
a manual switch for current limiting is provided.
Class 7000 vehicles are also equipped with a motor-driven air compressor, model S-MH58-C1000L, mounted beneath the floor, and a lozenge-shaped pantograph, model S-PS58, located on the roof at the rear.
The train features an electrically commanded braking system incorporating regenerative braking.
Accommodation
The cars have a mixture of longitudinal bench seating and transverse seating bays, both arranged symmetrically. The transverse seating bays have a pitch of 1,520 mm. Straps are fitted above the longitudinal seating. The passenger saloons employ 40 W fluorescent lighting arranged in two rows. The air-conditioning duct is fitted above the ceiling to improve interior design, and slit-shaped vents are used.
No toilet facilities are provided. The cab is of the compartment type, located on the left side of the train for conductor-less operation. Ticket machines, which issue tickets indicating the boarding station, are located behind the driver’s cab. Fare boxes are positioned beside the driver’s cab, and fare chart seven-segment displays are installed above the gangway door.
The master control handle adopts lateral motion.
Additional delivery
In 1992, twelve class 7000 vehicles and four class 7100 vehicles were additionally delivered to the Matsuyama Depot, and a further five class 7000 vehicles and three class 7100 vehicles to the Takamatsu Depot, in conjunction with the completion of the Yosan Line electrification between Kan-onji and Iyo-shi.
Modifications
Door operation buttons were installed adjacent to the doors to enable manual operation via push-button controls. Furthermore, a refurbishment programme for the traction system commenced in 2017.
Operations
The 7000 series entered revenue service with the opening of the electrified section of the Yosan Line between Iyo-Hojo and Iyo-shi in 1990, and was initially deployed on regional services on rural sections of the line. They were subsequently introduced on regional services of the Yosan Line between Takamatsu and Iyo-shi and the Dosan Line between Tadotsu and Kotohira, as well as on “Sunport” rapid services. However, the 7000 series was withdrawn from “Sunport” rapid services in 2025.
At present, the 7000 series is deployed on regional services of the Yosan Line between Takamatsu and Iyo-shi, and the Dosan Line between Tadotsu and Kotohira. |
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