Configuring a history extension

When a history extension is first added to a component, by default it is set to be disabled. All that is really necessary to enable data collection is to change the Enable property value to true. Of course, you will want to make other property changes to better configure data collection to suit your actual needs.

Prerequisites: A history extension has been added to a component.

This procedure describes steps to enable the history extension, configure a unique name and active period, as well as the capacity and full policy.

Perform the following steps:

Double-click on the history extension on the component to open the Property Sheet view.
In the Enabled property, click on the drop-down list and click true.
In the History Name text property, edit the default name (%parent.name%) to give it a unique name.
For example, if configuring the name for a history extension on the point, SpaceTemp1, that is under the device, AHU-1. You could add %parent.parent.name% just prior to the default name to end up with this:%parent.parent.name%_%parent.name%, which results in the unique name: AHU-1_SpaceTemp1.

NOTE: You can expand the History Config property to review the read-only Id value resulting from your entry for the History Name property. If you detect an error string here then the History Name property is incorrectly configured.
In the Active Period property, if desired click to change the default Days of week and Time Range values.
Expand the History Config property, and in the Capacity property, enter the maximum number of history records for the extension.

NOTE: Setting the capacity is important if you intend to archive history records to another location (station). Capacity is an arbitrary number that you determine based on the expected change frequency. A best practice is to set the capacity to hold two days worth of collected data on the JACE.
Also under History Config, confirm that the Full Policy property is set to Roll to prevent the extension from halting data recording when the specified capacity is reached. If not, click the drop-down list and click Roll.

NOTE: The Roll option implements a first-in-first-out method of overwriting the oldest records. Once the specified history capacity is reached, the next record collected overwrites the oldest record.

The history extension is configured and collecting data that is written to records in the History space. In a Chart view of the history you should see live data plotting and after a period of time historical data will be available as well.

Configuring a history extension

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