Niagara History Import Manager view

This is the default view on a station’s Histories extension.

Figure 57. History Import Manager under a NiagaraNetwork station

The New Folder button is available in this view for adding archive folders to organize import (or export) descriptors. Each folder has its own history manager view.

Add (or Edit) history import descriptor window

Figure 58. Add (or Edit) history import descriptor window

Property	Value	Description
Name	Text string followed by numbers	For a history originating in the local host station, the name begins with Local_ . If Discovered for import, typically left at default. For a system history export, originating in the remote station, the name begins with NiagaraSystemHistoryExport. NOTE: : There is a possibility of Niagara history import/export failures, with history names above the specified character limit for an older platform.
HistoryId	Text in two parts: /stationname/historyname	Specifies the history name in the local station’s History space, using two parts: “/<stationName>” and “/<historyName>”. If Discovered, station name is “^” (a character representing the device name of the parent container) and history name reflects the source history name. Typically, you leave both properties at default values, or edit the second (<historyName>) property only.
Execution Time — Daily (default)	Time Of Day hours:minutes:seconds AM/PM timezoneRandomizationDays Of Week	Defines when the daily export or import automatically takes place. The hours follow a 24–hour clock.
Execution Time — Interval	Interval hours:minutes:secondsTime Of DayDays Of Week	Defines the amount of time between automatic exports or imports. Hours may number in the thousands.
Execution Time — Manual	N/A	Requires human intervention to initiate a history export or import.
Enabled	`true` or `false`	Activates (`true`) and deactivates (`false`) the object (network, device, point, component, table, schedule, descriptor, etc.).
Capacity	Record Count: nnn (500 default), Unlimited	Specifies local storage capacity for histories. In general, 500 (default record count) or less is adequate for a controller station because those records are usually archived (exported) to a Supervisor station. For this reason, a very large number, such as 250,000 is acceptable for Supervisor stations. `Unlimited` is not the wisest choice even for a Supervisor station.
Full Policy	Roll (default), Stop	Applies only if Capacity is set to “Record Count”. Upon specified record count, the oldest records are overwritten by newest records. `Roll` ensures that the latest data are recorded. `Stop` terminates recording when the number of stored records reaches specified history capacity. Full policy has no effect if `Capacity` is `Unlimited`.
On Demand Poll Enabled	true (default), false	Determines user control over polling. `true` enables a system user to use the Live Updates (play) button in History views to poll for live data for the associated imported history(ies). `false` renders this button unavailable in history views for the associated imported history(ies).
On Demand Poll Frequency	Fast, Normal, Slow	References the On Demand Poll Scheduler rates under the NiagaraNetwork’s History Policies container slot.
System Tags	Text	This property allows you to assign additional metadata (the System Tag) to a history extension. This identifier is then available for selective import or export of histories using the Niagara System History Import or Niagara System History Export option (using the System Tag Patterns). Each System Tag is separated by a semicolon. For example: NorthAmerica;Region1;Cities.

Discovered selection notes

In the Niagara History Import Manager, discovered station histories are under an expandable tree structure organized by station name.

Figure 59. Expand stations to see all histories

Histories under the same station name as the parent Niagara Station (device) component are local histories for that station. Histories under any other stations represent histories that are either imported into (or exported to) that station.

For example, discovered histories (shown in the above image) for Niagara Station subCONT_A include local histories (expanded, top); another imported history from remote station, subCONT_B, is shown below.

NOTE: From any Niagara Station, you can import both its local histories and already-imported histories, as needed. However, unless circumstances warrant a “relay archive method,” it may be best to import histories directly from the source station whenever possible.