Train Operated Route Release, invented in the Southern Region due to the amount of traffic a signaller had to deal with. It involves the interlocking checking that a pair or trio of tracks have been correctly occupied and cleared in sequence and then releasing the route locking from the signal .
Where TORR is not provided, the signal will return to danger after the passage of a train but will not re-clear unless the signaller re-strokes the route. The signaller can instead pull up the button (on NX panel s) or turn the switch to the vertical position on Turn and Push panels.
See Keith Barber's post on the history of TORR .
Last edited by GeoffM on 15/09/2016 at 03:01