Section 18 in The Delhi Metro Airport Express Line, General Rules, 2010
18. Working of Signals and points.
(1)Control of signals and points shall be from a route setting panel or work-station, and complete routes, points and signals, will be cleared by a single operation under normal conditions.(2)Any failure of vital equipments shall cause the signaling system to display a more restrictive indication.(3)Any route which has been cleared for a train shall not be cancelled until it is cleared by the train entering the route except,-(a)in case of emergency; and(b)in case where operating conditions require that an alternate route be cleared and in this case, the alternative route shall not be made available for clearance until the pre-set time, defined under special instructions, has elapsed from the time the original route was blocked.(4)In conditions of failure of route setting controls, points can be set individually from Operations Control Centre, Station Control Room or locally as may be necessary.
