Siemens C651

Initial design

The trains have a full white body and a thick red stripe in the middle. Similar to the Kawasaki Heavy Industries C151 trains, the Siemens C651 trains have no visual passenger information systems, but have a built-in audio announcement system until the STARIS was installed and activated around 2010.

Unlike the 66 first generation Kawasaki Heavy Industries C151 train sets, the C651s are delivered with a scratch-resistant acrylic finish. This alleviated the difficulty of removing dirt trapped on the exterior surface, as opposed to the aluminium finish of the C151 trains that were delivered unpainted. ^[3] The run number at the front of the train was delivered by a low-power consumption electronic green flip-dot display. ^[3]

The C651 trains were originally delivered with a GTO-VVVF propulsion system that was supplied by Siemens. ^[3][4]

Other original features included specifically designed air-conditioning vents that eliminate dripping from the cooling system to the train compartments, as well as an event-recorder, which records important train functions, such as braking and emergency operations to assist troubleshooting in an event of a fault. ^[3]

Experimental programmes

Many experimental programmes have been run on the C651 cars, including the past program.

For the past program, the third and fourth cars, coloured in green were even more radical in the reconfiguration, with all but eight parts of seats, four at each ends of the car removed completely. In its place was standing room with upholstered cushion, in an attempt to provide a degree of comfort to passengers standing in that space. This design proved to be unpopular with the commuters, and it was eventually dropped. The original seats between the 1st and 2nd door, and the 3rd and 4th door on these cars have been replaced. The remaining upholstered seats were reverted to original seats in May 2006. All C151 trains had their seats on the middle part of carriage removed.

For now, some trains of this type were reconfigured to have more standing space in the late 1990s as part of an experimental programme. In particular, the second and fifth cars (the blue cars) were reconfigured to have more standing room on both sides, as 3 seats from some later cars.

More grabpoles were also added. Regular grabpoles in the centre of each car were replaced by grabpoles that branch out into three in the centre first in 2007, followed by triplicated hand grips and grab poles in 2014. Special non slip floorings were also tested.

• 
  Upholstered cushions, part of an experimental program. They have since been replaced by original seats.
• 
  Modified flooring of some cars of C651 Set 237/238 before Mid-life Refurbishment.
• 
  The interior of a Siemens C651 car before Mid-life Refurbishment. Modified grab poles and standing spaces, part of an experimental program, can be seen.

Refurbishment

A refurbished rail car of set 217/218.

In 2015, refurbishment contracts for the 19 C651 train sets were awarded to Singapore Rail Engineering (SRE).^[5] When completed, these upgrades will address train components such as doors and brakes that have been the primary cause of delays owing to train faults. The changes will include re-signalling, refurbishing the propulsion system, air-conditioning system, auxiliary power system, interior saloon with modifying handrails, replacement of the gangway connections and improving the exterior of the trains. Upgraded trains will also have sensors that carries vital information on the train’s state of health for improved operation and maintenance of the train set. ^[6][7]

Refurbishment works has begun since early 2016, beginning with train set 217/218. It will also include STARIS version 2.0, of which it will consist of the dynamic route map displays.^[8] In late August 2016, two prototype train cars have been built by SRE for evaluation, signalling that the project is unaffected by termination of the End-of Life Refurbishments for the 66 C151 train sets.^[9]. Many of the trainsets are beginning to be refurbished, with a few of them undergoing extensive testing. The first train will begin operations in September 2018 and the last train will complete refurbishment in 2020. ^[10][11]

Unfortunately, on 16 September 2018, SMRT Corporation (SMRT Trains) abruptly announced that Singapore Rail Engineering(SRE) will halt refurbishment works permanently, with about 3 units already refurbished. This is supposedly due to the New Rail Financing Framework(NRFF).^{[12] [13] [14]}