Signalling of the Toronto subway
Line 3 Scarborough used SelTrac IS, a transmission-based train control system originally developed by Alcatel-Lucent (now part of Thales Group) as part of the Intermediate Capacity Transit System (ICTS) technology employed by Line 3, which is identical to that of Vancouver's SkyTrain and the Detroit People Mover.
The system was designed to allow Line 3 trains to be driverless; however, due to safety concerns, an operator was stationed at the front of each train in a cab equipped with a display of signal indications; there were no track-side signals.
Transit Control at the Hillcrest Complex had a terminal connected to the Kennedy station computer.
[2] The TTC used "Urbalis 400", a communications-based train control system made by Alstom, on Line 1 Yonge–University.
It is engaged in a phased implementation of CBTC to replace the fixed-block signal system on the entire line.
[4] Effective September 24, 2022, Line 1 had been fully converted to automatic train control (ATC).
The track-level beacons transmit signals to onboard controllers installed on each train.
Onboard roof antennas (Data Communications System antennas) transmit information such as speed and location from the controllers to Trackside Radio Equipment which relays the data to central computers and to the TTC's Transit Control Centre.
However, this goal depends on how well the TTC can manage dwell time in stations, crew changeovers and turnaround at terminals.
Headway control, a method of evening out the spacing between trains, is active at certain stations with interlocking (or home) signals.
However, once the train ahead has travelled far enough for this signal to clear, the aspect does not immediately change but remains at red.
Once this timer reaches a predetermined time, the signal then clears as normal and the trip arm is lowered.
A flashing red without the lunar aspect (not included in the images above) would be used for the signal at the end of the last block of a GT section.
Station timing is used to reduce the separation distance between trains that are operating at slower speeds.
This reflects the shorter braking distance of a train travelling slower than the maximum permitted speed.
Signals that are on a northbound portion of track use the nearest even valued chain measure, where signals on a southbound portion of track use the nearest odd valued chain measure.
(no longer uses block signalling) (no longer uses block signalling) (no longer uses block signalling) In work zones, staff place yellow beacons on the track bed between the rails to inform train operators that a "slow order" is in effect; the first beacon is usually accompanied with a speed restriction sign indicating the speed limit for the affected area.
