REDUNDANT CONFIGURATION SUPERVISORY CONTROL SYSTEM, SUPERVISORY CONTROLLER THEREOF AND CONTROLLER TO BE SUPERVISED

PROBLEM TO BE SOLVED: To continue a supervisory control operation by automatically selecting a standby system supervisory controller, without the need for intervention of an operator and interrupting the supervisory control operation during execution with respect to selection of an active system of the supervisory controller in a redundant configuration supervisory control system. SOLUTION: On the occurrence of a fault in an active system supervisory controller 120, that applies supervisory control to a controller to be supervised via a connection setup with each controller 11 to be supervised being a component of a communication network, a connection is set up between each controller 11 to be supervised and a standby system supervisory controller 121, the standby system supervisory controller 121 recognizes a control operation, having been up to conducted immediately before the switching by the active system supervisory controller 120 and takes over the control operation after the recognized control operation and continuously executes the control operation for the controller 11 to be supervised.