OPC Source Systems

Supported Processes

All OPC agents supplied with PCo support the notification and query process.

In the notification process, if OPC agents are used, PCo continually transmits the tags and checks whether the stipulated conditions are met (exception: OPC DA source systems). If so, PCo sends a notification message to the destination system or systems.

If the source system is an OPC DA system, the source system checks the measurement values itself and sends only the deviating tag to PCo. PCo then sends the notification message to the destination system or systems.

Structuring of Tags

All data sources provided by an OPC DA server are organized in a namespace. This can be flat or hierarchical.

In a flat namespace, all tags lie on one level.

In a hierarchical namespace, the hierarchy nodes may represent the equipment and machines of a plant, for example. Leaves, which represent a temperature sensor or regulator, for example, are located on the nodes. The leaves are referred to as tags. Each tag has its own ID and can provide values.