The VisiWin system module Process data monitoring

VisiWin process data monitoring supplements the functions of VisiWin alarm management. While alarm management only allows the monitoring of process variable states, process data monitoring can also be used to monitor analogue variables for limit value violations, for example.

The system module contains the monitoring definition as a central element. This is where you specify which process variable or which definition is to be monitored by the server component, the criteria for monitoring this variable and what is to be done in the event of a monitoring event.

For example, in the case of limit value monitoring, the output of a monitoring event (a limit value being exceeded) takes place via the manipulation of another process variable value: If the value of the variable to be monitored exceeds one of the specified limits, a bit is set in the output variable.

This output variable can be used as a status display in the application. Defining the output variable as an event variable of an alarm from the alarm management also enables the centralised recording of a monitoring event in the alarm management. The parameters (text, appearance, acknowledgement, etc.) with which the monitoring event is to be displayed are then specified in the alarm definition.