Components of the VisiWin system module Process data monitoring

The following diagram shows the components of the VisiWin process data monitoring system module. The task of each component and the interaction of the components are explained below.

Variable server

As the central connection to the communication components, the variable server supplies the process data to be monitored and manipulated.

Process data monitoring server

During initialisation, the monitoring server reads the definitions specified in the project file. Process data that is to be monitored is registered with the variable server for monitoring, i.e. if one of these process values changes, the server is informed of this. The server then carries out the necessary calculations to determine monitoring events using the monitoring criteria defined in the project file.

Process data that are specified as output variables in the definitions are written to the variable server when a monitoring event is triggered.

Process data monitoring editor

The editor enables the configuration of process data monitoring. By specifying definitions in the project file, it enables the runtime behaviour of the monitoring server to be determined.

Project file

The project file contains the definitions for process data monitoring. The definitions contain information on which process value is to be monitored, under which criteria a monitoring event is triggered and what the event should result in. At development time, the definitions can be edited with the editor. At runtime, the definitions are read by the monitoring server. They determine the behaviour of the monitoring server and therefore the application.