Event categories

Events are assigned category numbers by the OPC AE server. However, category numbering conventions are not standard among different servers. Most OPC AE servers begin numbering event categories from 1, while others may start from a different index.

The interface always begins numbering event categories relative to 1. If possible, relate the lowest OPC AE server event category number to 1 and verify that each event category is listed sequentially. For example, an OPC AE server providing event categories 256, 257, 258, 371, 423 and 424 would be configured in the Interface Configuration Utility as shown in the figure below.

Note that event category 1 is configured such that it corresponds to event category 256 (the lowest event category number provided by this particular OPC AE server). Also note that OPC AE server event categories appear in the list sequentially, despite gaps between categories 258, 371 and 423.

Proper configuration of event categories is imperative when using location2 for event category filtering PI Point configuration