Historical Event Access
Historical Event Access addresses the handling of historical time series events. The AddressSpace of HEA Servers contains Historical Nodes representing the history of Event Sources (Objects or Views). HEA Clients deal with historical events by accessing these Nodes with the HistoryRead and HistoryUpdate Services.
Examples of historical events are:
- System alarms
- Operator action events
- System triggers (such as new orders to be processed)
Note – Historical Access is specified in OPC UA Part 11
Historical Event Access Capabilities
This capability indicates the base support of historical time series events including reading.
- Retrieval of SOE data.
- Root cause analysis.
Modify existing historized Events or add historized Events that are not in time series order.
- Storage of Events received late.
- Inserting missing Events.
- Correction of incorrect Events.
Ability to permanently remove historized Events.
- Removal of out of service data.
- Removal of redundant data.