GB1111932A - Improvements in traffic signalling systems - Google Patents

Abstract

1,111,932. Group traffic control. AUTOMATIC TELEPHONE & ELECTRIC CO. Ltd. 15 Aug., 1966 [18 Aug., 1965], No. 35450/65. Heading G4Q. A number of identical master controllers each controlling a number of local traffic controllers are interconnected to form a single group operating with a common cycle time under the control of a selected one of the master controllers. This " super master controller is selected by a signal from an allocator stepping switch which is connected to all the master controllers, the switch being driven manually, by time control or by a fault signal received from the selected " super " master controller. Each master controller may be arranged to operate on the same signalling plan, in which case all the other masters act as standby for the selected super master controller, or they may be arranged to have different signalling plans and be selected to operate at different times of the day or preferably each pair of master controllers are arranged with the same signalling plan, different from the other pairs, and one master then acts as a standby for the other master controller of its pair. During introduction of super master control or when the signalling plan is changed, the local controllers are disconnected from their masters during that part of the signalling cycle when the adjustment of the master timing takes place. Where the adjustment is large this is spread over a number of signalling cycles.