Functionality and concept description

The interaction of WinCC OA and OPC A&E looks as follows (whereas the OPC A&E can be from any producer , for example, that of WinCC OA):

A OPC A&E server only manages active alerts and events (A&E). OPC A&E clients report to server via (D)COM (via a subscription) and can thereby request filtered data. The OPC A&E client of WinCC OA II can process alerts/events from several OPC A&E servers.

The OPC A&E client can configure itself widely (see also Configuration of the OPC A&E client).

The alerts and events that the WinCC OA OPC A&E client receives from an OPC A&E server are shown in the alert panel of WinCC OA.

The possibilities of the WinCC OA alert handling and the OPC A&E alert handling are very similar but not congruent. A difference is , for example, the amount of possible states for acknowledgeable alerts. WinCC OA has an additional state "CAME - WENT/unacknowledged". On the other hand the A&E knows the state "disabled". The states are translated at the alert transmission accordingly (see the following table for the different states).

State in WinCC OA	State in OPC A&E
CAME / unacknowledged	Active / unacknowledged
WENT/ unacknowledged	Inactive / unacknowledged
CAME- WENT/ unacknowledged	Inactive / unacknowledged
CAME/ acknowledged	Active / acknowledged
No alert	Inactive / acknowledged
The alert is not passed on to the WinCC OA	disabled

Occurred alerts can be acknowledged continuous, this means that an alert can be acknowledged on each WinCC OA UI or OPC A&E client that is authorized to acknowledgement and the alert then appears on all other OPC A&E clients as acknowledged.

Note

Thereby, consider that the OPC A&E client does not acknowledge the alert itself but only sends an information to the OPC A&E server, which then acknowledges the alert.

When starting an OPC A&E client all alert states are automatically queried from the OPC A&E server and if necessary updated on the client.

The mapping of A&E objects to WinCC OA objects is done as follows:

OPC A&E	WinCC OA
Condition	Alert handling of a DPE. The following applies to the automatic configuration: A master data point with an alert handling is created for each condition.
Sub Condition	Alert ranges of the alert handling above. Thereby, consider that there is no sub condition for the valid range of the alert handling.
Server Item	A DPE in WinCC OA: The following applies for the automatic configuration: an instance of a master data point with alert handling (see condition) is generated automatically.

Important terms

The OPC A&E specification differentiates between:

Conditional Events (corresponds to the alert handling in WinCC OA)
Simple Events (simple alerts that are only shown but cannot be acknowledged)
Tracking Events (are not described in more detail since they are not implemented in WinCC OA).

These are the so called Event Types.

An important term in OPC A&E is the Event Category. An Event Category is a grouping possibility. Examples of Event Categories could be "Process-Events", "System-Events", "Batch-Events". An arbitrary number of Event Categories can be defined for each Event Type.

Caution

Only conditions (alert handlings) of a type can be combined in an Event Category, this means either Conditional or Simple Events.

A server item can trigger alerts/events for different Event Categories. The name of an Event Category have to be unique within a server. Each server producer can define own Event Categories.

V 3.11 SP1