ABS Flashcards
What is the object of the ABS and bi-directional system?
Allows two or more trains to proceed in the same direction but prevents them being in the same track section
On bi-directional lines to prevent trains running in opposite directions in a single line section at the same time.
How are opposite train movements prevented in single line running?
Home signals that protect the entrance at the opposing direction are sleeved at stop.
What are the station limits on the ABS system?
Between, the arriving home and the first automatic in advance of the departing home
Do station limits always contain a station?
No, they just indicate the area directly controlled by a signaller.
What signals are in block sections?
Absolute signals
What signals are in track sections?
Permissive signals
How can signals be controlled?
Locally or Remotely
What is a double line?
Dedicated up and down lines running in a single direction
What is a single line?
Bi directional running over a single line
How is the Object of ABS and Bi directional achieved?
- By securing signals at stop unless track section ahead is clear
- On bi directional track signals controlled by track circuits and displaying stop aspect preventing train from entering in the opposite direction
