Siemens SIMATIC PCS 7 Function Manual page 56

OpenPCS 7 interface
6.5 OPC Alarms and Events (OPC A&E)
Supported events
The OPC A&E server supports the following events:
● Condition-related event
● Simple event
● Tracking event
Condition-related events
With a condition-related event server, the event is associated with a condition. A condition may
be the limit violation of a tag. On the PCS 7 OS, a message will be generated as soon as a
limit violation occurs. This message is shown as an alarm in OPC A&E.
Simple event
Simple events are messages that inform the OPC A&E client about events. Simple events
include, for example, the launching and closing of programs.
Note
Note the following when using redundant PCS 7 OS servers:
Simple events that are linked to internal tags are sent twice when comparing tags. The first
message is triggered by the OS master server, the second by the OS standby server.
Tracking event
If a change is made in the process control system, the OPC A&E client will receive a message.
A change can, for example, be a change to a control parameter in the faceplate of the controller
or the suppression of messages in the message system.
Note
When filtering for all alarms of a plant section, make sure that you replace the source with a
wildcard in the filter text, because the source is only generated in runtime for a tracking event.
For example, the filter text for all events from the "Plant1\Unit1\Tank1" area is "Server
prefix::*Plant1\Unit1\Tank1*" and not "Server prefix::Plant1\Plant1\Unit1\Tank1*".
OPC A&E client
All OPC A&E clients complying with the OPC Alarms & Events 1.10 specification can access
the OPC A&E server. On the OPC A&E client, this can involve, for example, simple or complex
Microsoft Visual Basic or Microsoft Visual C++ applications. The use of individually developed
OPC A&E clients is the best way to meet the requirements. An OPC A&E client can, for
example, be used to analyze alarms or for the common archiving of alarms from different OPC
A&E servers.
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Function Manual, 05/2012, A5E02780178-02
OpenPCS 7