Hello,
I’m currently testing mappAlarmX in combination with mappConnect.
According to:
and
I should be able to subscribe to OPC UA events to gather the alarm information.
While reading the documentation of mappConnect and trying out different things, it seems to me that mappConnect doesn’t allow subscriptions to events. Normal variable subscriptions are working fine.
Am I correct that this is a limitation of mappConnect, or am I doing something wrong?
Thx
to the best of my knowledge you’re correct that this is a current limitation of mappConnect. While mappConnect supports OPC UA variable subscriptions (monitored items for data variables), it does not support OPC UA event subscriptions (Alarms & Conditions). The UA_EventItemAdd functionality exists in the AsOpcUac library for direct OPC UA client programming, but is not exposed through mappConnect.
Thanks for the answer. I suspected as much.
Is there a plan to add this functionality to mappConnect?
Not at the moment. If you really need it, you have to get in contact with sales or local support and create a product request.
Maybe the new implementation [since mappServices 6.6] via OPC UA can help you. From what I understand, this is without mappConnect but allows you to subscribe to events of mpAlarmX.
mapp AlarmX - OPC UA interface
OPC UA C/S information model AlarmX
There is a workaround to this by using the mappConnect standard OPC UA functionality and the mappAlarmX UI function blocks in the application. Then enabling the UIConnect variables on the OPC UA server and registering these as standard OPC UA subscriptions.
The blocks provide arrays with active and history alarm information.
That was what I was trying. I wanted to use the new OPC UA endpoint in AlarmX 6.6, but through mappConnect. Which doesn’t work since mappConnect does not support OPC UA Event Subscriptions.
Yeah, I saw that too. And I will probably use that as a fallback now. The event subscription solution would have been way nicer instead of having a ton of huge arrays exposed in OPC UA.