Kawasaki Heavy Industries & Nippon Sharyo 751B
- Not to be confused with Alstom Metropolis C751A and Alstom Metropolis C751C.
| Kawasaki Heavy Industries & Nippon Sharyo C751B 川崎重工业－日本车辆制造株式会社 C751B | |
 | |
| In service | 28 January 2000 - Current |
|---|---|
| Manufacturer | Kawasaki Heavy Industries and Nippon Sharyo |
| Constructed | 1999 - 2001 |
| Number built | Passenger service: 126 carriages (21 trains) |
| Formation | 6 per trainset DT - M1 - M2 - M2 - M1 - DT |
| Capacity | 1920 passengers 276/288 seats |
| Operator | SMRT Corporation |
| Depot(s) | Bishan, Changi and Ulu Pandan |
| Line(s) served | North South Line and East West Line |
| Specifications | |
| Car body construction |
Aluminium-alloy double- skinned construction |
| Car length | 23 m |
| Width | 3.2 m |
| Height | 3.7 m |
| Doors | 1.45 m, 8 per car |
| Maximum speed | 90 km/h (Design) 80 km/h (Service) |
| Weight | 34800 kg (DT) 39000 kg (M1/M2) |
| Traction system | IGBT-VVVF (Fuji Electric) Output 415 kVA 2 units per motor car (1C2M) |
| Engine(s) | Fuji Electric MLR109 Self-Ventilated Three-Phase AC Induction Motor |
| Power output | 140kW (550V 193A 1760 r/min) |
| Transmission | WN (Westinghouse-Natal) Drive |
| Auxiliaries | IGBT-VVVF (Fuji Electric) Auxilary Inverter with Battery Charger 80 kVA + 16 kW |
| Electric system(s) | 750 V DC 3rd rail |
| Bogies | Bolsterless Air Spring (Monolink Axlebox Type) |
| Safety system(s) | Automatic Train Control (ATC) Automatic Train Protection (ATP) |
| Gauge | 1,435 mm Standard gauge |
Kawasaki Heavy Industries & Nippon Sharyo C751B cars are part of the rolling stock used in Singapore's original Mass Rapid Transit network, operating on the North South Line and the East West Line since early 2000. 21 trainsets of 6 cars each were purchased, and it is the first rolling stock to feature VVVF Insulated Gate Bipolar Transistor traction control system. Kawasaki Heavy Industries manufactured 66 cars and Nippon Sharyo manufactured 60 cars respectively with one differences (trains built by Kawasaki Heavy Industries had 276 seats while trains built by Nippon Sharyo has 288 seats), even having built to agreed specifications. Kawasaki Heavy Industries & Nippon Sharyo C751B is the third generation of rolling stock to be used on the North South and East West MRT Lines.
Fleet
Exterior design
The most prominent difference between these trains, and trains of the older generation, such as the Kawasaki C151 train before refurbishment, are in terms of its exterior design and colours. The front of the train sports a more slanted and streamlined look, with the run number display in Orange LED Display. The sides of the train, instead of having the conventional white background with a red stripe, consists of a shiny black area covering the middle portion of the train from just above the windows to below the windows, followed by a bold red stripe and a thinner grey stripe at the bottom of the train.
Interior design
All cars are equipped with 6 Liquid Crystal Displays per car (which have since been deactivated), and all except Train 347/348 feature LED displays (which have been replaced by the VFDs of the STARIS system). These used to show rail travel information, commercials and movie trailers. They also come with more grab poles, wider seats, more space near the doors and wheelchair space. The interior and exterior design of the train have been improved, incorporating a much sleeker design. The LEDs however have seen little usage after a new series of voice announcements were introduced across the system in mid-2008. 327/328 is the only one to have VPIS working in 2009; and in 27 July 2010, STARIS were installed on 319/320 and 321/322 as demonstrators, followed by the rest of the C751Bs from September 2010. All VPIS were removed to make way for the STARIS.
The colour layout on these trains are also different from their earlier counterparts. Cars 1 and 6 use a sort of pinkish-purple color on the seats, while cars 2 and 5 use a different shade of blue, and the middle cars using a bluish-green. All door panels and walls are white, which was subsequently adopted in the refurbishment of the C151 cars.
Equipment
Main Propulsion Controller/Motor
The C751B is the second commuter type Electric Multiple Unit (EMU) made in Japan to feature electric systems fully manufactured by Fuji Electric. Propulsion is controlled by VVVF Inverter with 2-level IGBT semiconductor controller, rated at 415 kVA. Each inverter unit controls two motors on one bogie (1C2M), and one motor car features two of such units. Motors are three-phrase AC induction type, model MLR109, with a maximum output of 140 kW.
Bogies
The C751B uses the monolink axlebox type bolsterless air spring bogie. There are no major technical difference between a trailer and motor car bogie other than additional electrical components for the latter.
Auxiliary Systems
A break from tradition, the C751B features auxiliary inverters for its electrical systems on all six cars of the train. Previously, auxiliary inverters are mounted only on motor cars. The VVVF Inverter is controlled by IGBT semiconductors and rated at 80 kVA. A battery charger is built with the inverter and provides 16 kW output.
Experimental programmes
In 2001, when the Changi Airport Extension was opened, some of these trains plying the East West Line had luggage racks installed. These luggage racks were installed in every carriage of the train, taking up the space of two seats next to the door at the end of each carriage. The purpose of those racks were to let travellers heading to the airport, who usually carry a large amount of luggage, to have a space to place their bags easily.
However, these luggage racks were always underutilised. Travellers preferred holding on to their bags where they were standing or sitting, as opposed to placing them on the luggage racks, probably due to convenience and fear of theft. Some commuters were also complaining that these racks took up critically needed space which could be occupied by other passengers which often filled the train. Furthermore, the service to Changi Airport was cancelled and replaced by a shuttle service to and from Tanah Merah station, dismissing the need to provide these racks for non-airport bound train services. Therefore, in 2003, trains with the luggage racks had them removed, and replaced with an empty standing area, with a dual purpose of serving as a wheelchair area.
SMRT Active Route Map Information System
All C751Bs STARIS are operational.
Train withdrawal incidents
On 13 April 2002, a fault was detected in a C751B train and was subsequently withdrawn to the Changi Depot for investigations. As the train is under warranty, the engineers from the manufacturers of the train and gearbox flown in on 21 April and they detected that the gearboxes had metal fragments found in it on 22 April. When they found out the other 20 trains had fragmented gearboxes on 23 April 2002, SMRT withdraw all 21 C751B trains and suspended the Boon Lay - Changi Airport train through service and replaced with the Tanah Merah - Changi Airport shuttle service. Train's frequency was also adjusted until early May when 8 trains returned to service. By June 2002, all C751B trains had return to service and the through service was resumed.
Safety systems
Kawasaki Heavy Industries & Nippon Sharyo C751B cars are equipped with Automatic Train Control (ATC), supplemented with Automatic train operation (ATO). At a fallback level, Automatic Train Protection (ATP) is available.
Serial number
The car numbers of the trains range from x311 to x352, where x depends on the carriage type. Individual cars are assigned a 4 digit serial number by the rail operator SMRT.
- The first digit depends upon whether the car is the first, second or third car from the end of the train it is nearer to, where the first car has a 3, the second has a 1 & the third has a 2.
- The other 3 digits is the train identification number. A full length train of 6 cars have 2 different identification number, one for the first 3 cars, and the same number plus 1, for the other three. The smaller number is always at the front. For example, train 333/334 would consist of 6 cars with serial numbers, 3333, 1333, 2333, 2334, 1334, 3334 respectively. A full train of 6 cars can also be split into two 3-car sets each. In this case, set 333 (consisting of cars 3333, 1333 and 2333) and set 334 (consisting of cars 3334, 1334 and 2334) are coupled together to form 333/334.
- There have been cross-couplement cases in the past in which two different sets from two different trains of the same rolling stock were coupled together. This usually happens when one set undergoing maintenance while the other set is not, and so trains are cross-coupled to maintain frequency and to increase carrying capacity of the line. Cross-coupled trains are usually referred to with a hybrid set number (for example, 334/335 for a cross-couplement between sets 334 and 335.) The best way to check if a train is cross-coupled is to walk between the 2*** cars (3rd and 4th cars) and check if the two car numbers are consecutive (e.g. 2333 and 2334) where the odd number is the smaller of the two numbers.
- The reason why the car numbers begin with x311 is because there is a 4-car version of the C151 bearing the set number 301/302. It used to be a money train and is currently used by SCDF for training purposes.
- Kawasaki Heavy Industries built sets 311/312, 315/316, 319/320, 323/324, 327 - 334, 343/344, 347/348, 351/352. (11 trainsets)
- Nippon Sharyo built sets 313/314, 317/318, 321/322, 325/326, 335 - 342, 345/346, 349/350. (10 trainsets)