Alstom Metropolis C751A

Alstom Metropolis C751A
Front of an Alstom Metropolis C751A at Sengkang Depot.
Inside an Alstom Metropolis C751A car on the North East line. Trains running on this line are driverless and fully automated.
In service	20 June 2003; 18 years ago (2003-06-20) – Present
Manufacturer	Alstom
Built at	Valenciennes, France
Family name	Metropolis
Constructed	2000 – 2003
Entered service	20 June 2003; 18 years ago (2003-06-20)
Refurbished	CRRC Nanjing Puzhen 2019 - 2024
Number built	150 vehicles (25 trains)
Number in service	138 vehicles (23 trains, 2 under refurbishment)
Formation	6 per trainset DT-Mp-Mi+Mi-Mp-DT
Fleet numbers	7001/7002 – 7049/7050
Capacity	1920 passengers 298 seats
Operator(s)	SBS Transit Ltd (ComfortDelGro Corporation)
Depot(s)	Sengkang
Line(s) served	NEL  North East line
Specifications
Car body construction	Welded aluminium
Car length	23.65 m (77 ft 7+1⁄8 in) (DT) 22.8 m (74 ft 9+5⁄8 in) (Mp/Mi)
Width	3.2 m (10 ft 6 in)
Height	3.7 m (12 ft 1+5⁄8 in)
Floor height	1,100 mm (3 ft 7+1⁄4 in)
Doors	1,450 mm (57+1⁄8 in), 8 per car, 4 per side
Maximum speed	100 km/h (62 mph) (design) 90 km/h (56 mph) (service)
Weight	230 t (230 long tons; 250 short tons) (6 passengers/1 m2 or 11 sq ft)
Traction system	IGBT–VVVF (Alstom ONIX 1500)
Traction motors	16 × 150 kW (200 hp) 3-phase AC induction motor
Power output	2.4 MW (3,200 hp)
Acceleration	1.1 m/s2 (3.6 ft/s2)
Deceleration	1.4 m/s2 (4.6 ft/s2) (Emergency)
Electric system(s)	1,500 V DC overhead catenary
Current collection method	Pantograph
UIC classification	2'2' + Bo'Bo' + Bo'Bo' + Bo'Bo' + Bo'Bo' + 2'2'
Bogies	16 t (16 long tons; 18 short tons) per axle
Braking system(s)	Regenerative and pneumatic
Safety system(s)	Alstom URBALIS 300 moving block CBTC ATC under ATO GoA 4 (UTO), with subsystems of ATP, Iconis ATS and Smartlock CBI[1][2]
Coupling system	Scharfenberg coupler
Track gauge	1,435 mm (4 ft 8+1⁄2 in) standard gauge

The Alstom Metropolis C751A is the first generation of communications-based train control (CBTC) electric multiple unit rolling stock in operation on the North East line of Singapore's Mass Rapid Transit (MRT) system since 2003. 25 trainsets were purchased for the line.

Overview[]

Door of the C751A train

The six-car trains on the North East line are powered by overhead catenary, a first in Singapore's MRT history. Rolling stock on all the other operating lines are powered by a third rail because authorities considered overhead wires to be unsightly and did not allow for trains to be powered using this method on elevated lines. Since this line is the first to be fully underground in Singapore, the authorities had a choice between powering the trains on this line by overhead catenary or third rail. This rolling stock is the first to have seats of the same colour in every compartment of the train.

Alstom was contracted in 1997 and 1998 (as Contract C751A) by the Land Transport Authority (LTA) in Singapore to supply for trains for the North East line.^[3]

Platform gap reducers were since added to all C751A trains, similar to those on the C830C and C751C.

Refurbishment[]

In December 2018, LTA announced that the C751A trains will undergo mid-life refurbishment works from 2019 onwards. A contract worth $116.7 million was awarded to CRRC Nanjing Puzhen for the refurbishment works. All 25 first-generation C751A trains will be upgraded. The trains' interior, such as seats, panels and flooring, will get a facelift, and the air-conditioning, ventilation and passenger information systems will be upgraded. Works are expected to be completed by 2024.^[4]

Exterior Design[]

Red and purple stripes run along the train livery for passengers to easily identify that the trains are operated by SBS Transit. The fleet numbers were placed on the roof above the 1st and 4th doors on each carriage and three SBS Transit logos are placed per side per carriage. C751A trains do not have a middle window cut out which can be used to see the tracks, unlike the newer driverless trains in the system. This is because it has to make way for the old detrainment ramp, which is not as compact as that of the C751C, C830 and C830C.

Interior Design[]

The interior colouring scheme of the trains is largely different from other trains in the system, with beige being used for the roof, the emergency communication button and the top ends of the seats, and lavender for the lower parts of the seats. Wheelchair spaces are located at the 9th and 16th doors of the trains. 36 LCD displays had been installed on the trains but they were deactivated. These trains had two side windows at each end for viewing the tracks, but there was no middle window cut into the emergency train exit, which was only introduced starting with the C830 trains. Moreover, manually driven trains may be deployed during peak hours. Passengers would thus have difficulty in viewing the tunnel from either the front or behind.

In addition, the C751A trains are also fitted with the following:

• 2 Visual Passenger Information System (VPIS) screens installed in each train car. These displays show the name of the next station, current station, door closing messages and occasionally the date and time.
• 6 LCD screens are installed on the overhead panel in each train car. These screens formerly showed rail travel information of the next station and terminating station, silent commercials and safety videos. The units have since been deactivated due to lack of demand and may be removed during refurbishment.^[5]

Driverless operation[]

The fully automated operation of the North East line trains allows for passengers to view the tracks on each end of the trainset

The C751A is the first fully driverless heavy metro rolling stock in Singapore, being introduced in 2003. However in some situations, such as the event of disruptions, SBS Transit hires employees trained to drive the trains manually.^[6]

The C751A uses the URBALIS 300 moving-block communications-based (CBTC) Automatic Train Control (ATC) system, which optimizes headway and enables extra trains to be injected automatically into the system at rush hour to increase passenger capacity and reduce congestion. In the depot, trains are also operated in full automatic mode. Communication between the train and the fixed signaling equipment is enabled by the IAGO two-way continuous transmission system. Station-based automatic train supervision ensures a greater degree of availability. Built-in test equipment has also been included, and Eurobalise standards have been adopted for spot transmission.^[3]

Experimental Programmes[]

• Some of C751A trains had been installed four rows for standing area to take away 28 seatings in between two doors in middle four carriages. This creates space for more commuters to board, especially during peak hours.

Train Formation[]

The configuration of a C751A in revenue service is DT-Mp-Mi+Mi-Mp-DT

The car numbers of the trains range from 7x001 to 7x050, where x depends on the carriage type. Individual cars are assigned a five-digit serial number by the rail operator SBS Transit. A complete six-car trainset consists of an identical twin set of one driving trailer (DT) and two motor cars (Mi & Mp) permanently coupled together. For example, set 7011/7012 consists of carriages 71011, 72011, 73011, 73012, 72012 and 71012.

• The first digit is always a 7.
• The second digit identifies the car number, where the first car has a 1, the second has a 2 & the third has a 3.
• The third digit is always a 0.
• The fourth digit and fifth digit are the train identification numbers. A full length train of 6 cars have 2 different identification numbers. For example, 7011/7012 (normal coupling) or 7011/7022 (cross coupling).
• Alstom built sets 7001/7002-7049/7050.

See also[]

• Alstom Metropolis

References[]

External links[]

Wikimedia Commons has media related to Alstom Metropolis C751A.