Section 19(6)(i) in The Delhi Metro Airport Express Line, General Rules, 2010
(i)Local operation of points on running lines as and when required may only be undertaken by a Station Controller with the permission of the traffic controller as the crank handle used to manually operate the points is interlocked through a key which, when released by Operations Control Center controller or Station Controller, shall inhibit setting of routes over the points concerned, and such transfer of control should be acknowledged by the station controller before the local control can be activated;