OPC UA AC to OPC AE translation

[JiriKocian]

Hello,
I am struggling with OPC UA AC to OPC AE translation (to be able to read alarms and events in PI Historian - does not have OPC UA AC interface to read alarms and conditions). We have 3 machines with OPC UA servers:

I can read OPC UA AC messages in UaExpert OPC UA client with no problem:

What I have understood so far the machine has strange Identifiers. It has 10000 for dpChangeMessages and 10010 for dpAlarms.
I do not think it corresponds to Identifiers defined by OPC foundation.
I try to map these identifiers in OPC AE tab in Event Category Mapping:


But I cannot see any message in Matrikon OPC DA client:

I already investigated that and saw problems with filtering in Matrikon OPC client. I tried to enable all. You can see hat "BaseEventType" is 4 times in the list.
Do you have any idea what to check ?

Additional general questions:
1) If I set nothing in Event Category Mapping - this is the case that Gateway maps all ? Or I should always specify what I want to translate ?
2) Do I need to specify anything in Attribute Mapping also ?
3) How Namespace index is important to specify in Event Category Mapping ?

Thank you a lot for your support.

Regards,

Jiri

[JiriKocian]

http://kocianjiri.wz.cz/fotos/UaExpert4.png
http://kocianjiri.wz.cz/fotos/UaExpert3.png
http://kocianjiri.wz.cz/fotos/UaExpert2.png
http://kocianjiri.wz.cz/fotos/UaExpert.png

[Support Team]

Hi,

yes, the mapping tables for the "Categories" and the "Attributes" will be created automatically on first "query" by a classic AE client. Therefore typically there is no need to do anything for configuring it (if a client can not query them, it probably can not use them anyways). However as you already mentioned, this could become a quite large mapping table, which in turn may create an issue in the size of the "filter" that the AE Client must configure. E.g. in the old days typical AE servers had 20-40 Attributes, UaGateway can aggregate up to 100 UA server, which each can have hundrets of EventFields, which will be presented within one classic A&E server of the UaGateway. For the Matrikon-Explorer (or any other client) this looks like pretty decent list it its filter dialog.

general answers:
1) If I set nothing in Event Category Mapping - this is the case that Gateway maps all ? Or I should always specify what I want to translate ?
-> mapping is done on first query, you may want to "reduce" later to simplify.
2) Do I need to specify anything in Attribute Mapping also ?
-> you could do manually if your AE client is not asking "QueryAvailableAttributes" (which would have triggered the automatic mapping). Again you may want to reduce thereafter to simplify filtering for the classic AE client.
3) How Namespace index is important to specify in Event Category Mapping ?
-> yes the namespaceindex is always essential part of the ID (an ID is only unique within one namespace). In your case even more important, because you are aggregating the namespaces of 3 underlying UA servers.

[Support Team]

Hi,

after digging into the topic more detailed the issue was located in the OPC UA Server implementation (Fette Compacting), but not in the UaGateway.

As already described in previous post, typically you do "not need to do anything" for the configuration of the Category and Attribute mapping inside UaGateway. This is done "automatically on first query" through the UaGateway. When being queried by the AEClient, the UaGateway investigates the underlying UA Servers, and fetches all required data automatically, and creates a (rather large) mapping list.

However, this particular FetteOpcUaServer does not provide the correct information (or an incomplete set of information) in it's address space. Because of that, the UaGatway's automatic mapping function can not fetch all the required information.

Workaround: you can configure "manually" the missing EventTypes and map them to Categories in the UaGateway. Here you must use the correct namespace (index), which is different form the original when being mapped through the UaGateway.

Hint: when using the Matrikon-Explorer (for testing), you best use "no filter" selection at all, and you will get "everything".