| [[Alstom Metropolis C830 trains in Kim Chuan Depot.|250px]]|
Alstom Metropolis C830 trains in Kim Chuan Depot.
The Alstom Metropolis C830 are the second generation of communication-based train control (CBTC) rolling stock to be used in Singapore’s Mass Rapid Transit (MRT) lines. Alstom was contracted in 2000 (as part of turnkey contract C830) by the Land Transport Authority (LTA) in Singapore to supply the trains for the Circle MRT Line.
The automated system version, previously known as “moving block systems”, CBTC systems do not require traditional "fixed-block track circuits" for determining train position. Instead, they rely on "continuous two-way digital communication" between each controlled train and a wayside control center, which may control an area of a railroad line, a complete line, or a group of lines. Recent studies consistently show that CBTC systems reduce life-cycle costs for the overall rail property and enhance operational flexibility and control.
Despite being similar to the fully underground North East MRT Line, the decision was made to power the three-car trains along the upcoming Circle MRT Line by third rail instead of overhead catenary. 40 trainsets of three cars each were purchased for the Circle Line.
These cars, although similar to their counterparts running on the North East Line, do not feature LCD displays in each car. Also, the front of the train features an extra window cut into the emergency exit door, something lacking in the North East Line trains.
- The first digit of a car's serial number is always an eight.
- The other three digits is the train identification number. A full length train of three cars will have three different consecutive serial numbers. The second and third digits are used to identify the train, while the last digit denotes the carriage of each train. In a full length train, the numbers will end with 1, 2 and 3.
A typical SMRT Circle Line train, for example, would consist of serial numbers 8031, 8032, 8033.
The trains are coloured in black and have a red stripe below it. As for the interior, the seats are pink, blue and green.