History import and export
Each station can both export and import history data. In practice, data are collected locally in remote controller stations.
Connected to a remote controller station, you can export those history data to a
Figure 21. Station history components in a target station
The graphic identifies all the station components that relate to histories. The component paths are designed to imitate the location of each component in a Nav tree.
- The HistoryService manages the history database in the local station. The local station is the station you are currently connected to. This table view has a row for each local history.
- History Policies (History Network Ext on the NiagaraNetwork Property Sheet) is a container for the On Demand Poll Scheduler, the default configuration rule and other configuration rules.
The poll scheduler sets up polling frequency and reports polling status for imported histories. Usually these are histories transferred from a remote station to the
History policies select which histories to export from a remote station to a target station. Unlike imported histories, which let you define and adjust capacity and full policy properties later, if needed, the histories a station exports to another station have no associated component—only the history itself. The target station’s history policies set the capacity and full policy properties at creation time for each exported history.
- The History Import Manager contains an import descriptor for each type of history. Each descriptor defines the name and ID of the history, when to pull
it from the source station and how to manage the target database. You use the History Import Manager when you are connected to the
The History Export Manager (selected from the drop-down list) contains an export descriptor for each type of history. Each export descriptor defines the name and ID of the history and when to push it from the source (local station) to the target station. You use the History Export Manager when you are connected to the remote station and intend to push data to the
- The History space (history-FoxHistorySpace) charts the histories in the local station.