Siemens SIMATIC OpenPCS 7, Руководство по эксплуатации функций

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When acknowledging messages, a distinction must be made between "pending" messages
and "historical" messages.
● Pending messages
Messages received over the path specified by OPC A&E (for example, "Refresh") can be
acknowledged.
● Historical messages
Messages received over the "historical messages" path (extension of the Siemens OPC
A&E server) cannot be acknowledged.
Additional information
● For additional information about "OPC - OLE for Open Connectivity" refer to the
WinCC
Information System.
● Additional information about the OPC A&E can be found in the specification
OPC Alarms
& Events 1.10.
6.5.3 Mapping the PCS 7 OS message system on OPC A&E
Introduction
In PCS 7, program functionality in the automation system is configured using messaging
capable CFCblocks from the PCS 7library. After compiling the PCS 7 OS, the configuration
messages exist in the PCS 7 OS message system. These messages are mapped to the OPC
A&E standard by the OpenPCS 7 station implementation. The OS configuration defines which
event in the process triggers a message.
Mapping the OS message system on OPC A&E with hierarchical access
In PCS 7, the following standard settings in the OS message system are used for mapping
messages on OPC A&E:
● The source of a message is mapped on the OPC source.
● The message text of a message is mapped on the OPC message.
Overview
The OPC attribute class OPCEvent is used in OPC A&E to display events. The following table
shows selected OPC attributes and their meaning in the OS message system.
The events that use the configured attributes are shown in the third column of the table:
● "S" means a simple event
● "C" means a condition-related event
● "T" means a tracking event
OpenPCS 7 interface
6.5 OPC Alarms and Events (OPC A&E)
OpenPCS 7
Function Manual, 05/2012, A5E02780178-02
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