Important note about OPC UA Histories
When you discover and add histories in the OPC UA client, they are automatically stored in two locations. Adding histories using the History extension places them under the respective driver name within the history section. Similarly, when you add a point with history to the Point device extension, it appears under the station history.
OpcUaClientPointDeviceExt: When you identify a point with a history on the discovered OPC UA server in the OpcUaClientPointManager view, adding this point to the station as a Niagara point will automatically create an ImportHistoryExt as a subordinate to the control point. By default, these histories are located under the station History.
OpcUaClientHistoryDeviceExt: Each OpcUaDevice includes an OpcUaClientHistoryDeviceExt. This device extension’s OpcUaClientHistoryImportManager view allows you to uncover all histories collected by the connected OPC UA Server. When you discover and add these histories, the system retrieves and stores the history of that particular point under the client driver name within the History.
Preferably, you should add histories to the Points device extension. However, it is possible to collect histories without creating a Control Point by utilizing the Histories device extension..