Using relative history extension Ords with the HistoryPointList
You can use relative paths to point to history extension ords when using a HistoryPointListItem component. This “relativized” format facilitates portability, allowing you to copy the device (with HistoryPointList) to other locations without having to correct the Ords for each new location.
Prerequisites:
- One or more devices in the station logic.
- One or more points (with history extensions) are under the device(s).
Perform the following steps:
- Drag a HistoryPointList component from the palette to a device (Air Handling Unit, VAV, etc.).
- To open the component’s Property Sheet, double-click the HistoryPointList component.
- Drag a HistroyPointListItem component from the palette to the HistoryPointList component and double-click it to open its Property Sheet view.
- Click on the
ORDproperty and use the Component Chooser to select the desired history extension.The absolute Ord for the selected history extension displays. For example, station:|slot:/Logic/Playground/batchHistories1/ZoneTemp1/NumericInterval - Edit the absolute Ord so that it is relative to the history extension’s parent Ord. For example, slot:../ZoneTemp1/NumericIntervalIn this example, the starting point for relativizing the Ord is the HistoryPointList component. Entering ../ has the effect of stepping up one directory in the path to the parent component containing both HistoryPointList and ZoneTemp1
- Repeat these steps as needed to populate the HistoryPointList.
- Copy the device to one or two other locations, enable the duplicated history extensions and note the automatic changes to HistroyPointListItem Ords.
The HistoryPointList component takes care of resolving the Ord path for each HistroyPointListItem. The example below shows relative Ords to history extension in HistroyPointListItem.
