Honeywell 900RSM - 0200 Redundant Switch Module DCS Control System The Redundant Switch Module resides in a ControlEdge HC900 Redundant controller rack and interfaces with both CPUs of a redundant system and indicates which CPU is functioning as the Lead controller and which is the Reserve. A key switch on the module sets the mode of both the Lead and Reserve controllers, guaranteeing synchronization of CPUs. A momentary contact position of the key switch allows the user to
