Alarm and events on user defined entity node?

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Andreas
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Joined: 17 Sep 2012, 08:32

Alarm and events on user defined entity node?

Post by Andreas »

I would like to publish events to a user defined node instead of they ending up on the Server node and do a similar thing for alarms. At the moment we publish events through the nodemanager and they are received by the Server node. Alarms are also connected from the Server node but it adds clutter to the model and having an Area folder just to organize things feels unnecessary. Is this possible or is the examples you have and using the Server node as origin the only way of doing this?

I would also like to know how historical data access connects to this topic. Can we receive all published events on the server through historical data access?


Thanks!

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Support Team
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Re: Alarm and events on user defined entity node?

Post by Support Team »

Hi Andreas,

Event MonitoredItems are created with Object nodes that have the EventNotifier attribute set to SubscribeToEvents. The Server Object must be such a node if the server supports events. All events from a server can be received through the server object.

You can set the EventNotifier attribute on any object node and then a client can receive events from this node and its children through this Object or through the Server object.

Area Object nodes can be used to build an event notifier hierarchy but they are not necessary.

Historical Access functions for data cannot be used to read event history. There is a dedicated HistoryRead for Events function that takes the same event filter like an event monitored item and is also called on a Object that has the HistoryRead flag set in the EventNotifier attribute.

If you cannot find the right examples in the SDKs you should ask for the SDK you are using in the product section of the forum.

Best Regards,
Unified Automation Support Team

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