CBTC Flashcards
CBTC
Communication Based Train Control
ATC
Automatic Train Control
ATO
Automatic Train Operation
ATP
Automatic Train Protection
What two sub-systems make up ATC
ATO and ATP
What is ATC
The automatic Train Control system comprising the two sub-systems ATO and ATP
What is ATO
Automatic Train Operation - the sub-system that automates control of the train by regulating Motoring, Coasting, Braking and Stopping at Stations without the requirement of a train operator
What is ATP
Automatic Train Protection - the sub-system that continually compares the actual train speed of all communicating rail traffic with the maximum safe speed
What is a Carborne Controller
Onboard computer that controls the interface CBTC & Wayside devices to safely manage the train in UTO & PM modes
DCS
Data Communication System
What does the DCS do
Provides a communication link between ATC, ATS, MSS and CBI to enable constant communication between the sub-systems
ATS
Automatic Train Supervision
MSS
Maintenance Support System
CBI
Computer Based Interlocking
What is ATS
A centralised sub-system of CBTC used to load timetables and automatically setting routes according to timetable requirements.
In ATS, what happens once the timetable is uploaded
Routes, train launch, stopping patterns, dwell times and allocation of run numbers are automatically performed by the ATS system without operator intervention.
What is the standard Dwell Time
30 seconds
What is CBI
Sub-system that manages interlocking functionality, which is setting routes and ensuring safety during route setting. It handles the control of all Wayside equipment such as Points, Signals (PPI), PSDs and PEBs
PPI
Point Position Indicator
What are the six CBTC sub-systems
ATC - Automatic Train Control
ATS - Automatic Train Supervision
MSS - Maintenance Support System
DCS - Data Communication System
CCTV - Closed Circuit TV
CBI - Computer Based Interlocking
CCTV
Closed Circuit Television
What is CCTV
Fixed cameras that monitor designated areas. Some CCTV cameras have Pan Tilt Zoom where is is required to track people
CLC
Central Logic Computer
What is CLC
Central logic computer which manages all signalling and interlocking
What is the Fixed Block Principle
Fixed Block system uses axle counters as SDD through the Central Logic Computer (CLC). The secondary device tracks train locations and track occupancy to ensure a train does not move into a set block until it is unoccupied.
SDD
Secondary Detection Devices
In Fixed Block, a PPI will indicate PROCEED when
The block beyond the PPI is unoccupied
There are no conflicting routes set
The points are correctly set and locked
What is the Moving Block Principle
Allows the real time regulation and safe separation of rail traffic using ATP generated by the ATC sub-system. Rail traffic continually communicates speed, location and status of vehicles to maintain safe separation.
Localisation
Primary detection of Rail Traffic in the CBTC system
In Moving Block where is information sourced from
Beacons
Carborne Controller
Mechanical Odometer
What is CBTC
Railway signalling system that uses telecommunications between trains and track equipment for traffic management and infrastructure control.
Advantages of CBTC System
Optimise train speeds to gain best line capacity (headways)
Minimum trackside equipment
Automated Operations
Easy Integration
Driverless - reduces cost
Power saving
Easy expansion
