niagaraDriver-NiagaraHistoryDeviceExt
This component is an implementation of HistoryDeviceExt. A device’s Histories extension serves as the parent container for history descriptors—components that specify how history-type collections (log data) are imported or exported. By default, it also contains a Retry Trigger.
Only drivers that provide local data logging have this component. This includes the NiagaraNetwork’s NiagaraStation, ObixClient, R2ObixClient and BacnetDevice (under this device, this extension is named Trend Logs). Database device components in any of the RdbmsNetwork drivers (rdbSqlServer, rdbMySQL, etc.) each have a Histories extension.
To access these properties, expand , right-click Histories and click .
| Property | Value | Description |
|---|---|---|
| Retry Trigger | additional properties | Defines how frequently to
attempt a failed operation again. This continues until successful
execution occurs. Appears in the Nav tree but not in any manager view and is unique in that it requires no linking of its output for operation. Getting Started with Niagara documents Retry Trigger properties. |
Retry Trigger action
By default, device extensions like Histories, Schedules, and others contain a Retry Trigger.
If a descriptor component (that is, a history import descriptor, schedule import descriptor, and so on) fails, the Retry Trigger defines subsequent retries that automatically occur at the defined interval (default value is 15 minutes). This continues until a successful execution occurs.
If the histories descriptor fails, right-clicking Retry Trigger and click manually triggers the histories descriptor again.