User Manual

Trend Viewer
9 TrendViewer
This section describes the trend viewer object. Trend Viewers are used to present
chronological data from controller tags. The curves in a trend vie wer can have
different sources of data.
Thesourceofdatacanbealogitemforadatalogger.Thevaluesofthetag
connected to the log item is then stored in the projects database.
The source can also be a Tag. The trend viewer curve then on ly shows real-time
valuesandisstoredinaRAMcache.
When changing the system time in the panel to a later time, then data will be
logged with the new time. In the trend viewer there will be a straight line between
the last point logged for the old time and the first point logged for the ne w time.
If the power to the panel is cut or if there is a communication error, then there will
beagapinthetrendviewercurveforthetimeperiodwherenosignalwasreceived.
Relatedinformation
Database
Database Export
9.1 DefiningTrendViewerObjects
It is possible to define several independent trend viewer objects, in the same screen
or in different screens. The number of trend viewer curves is limited only by the
available amount of memory in the panel.
Note:
Alargenumberoftrendviewerpensand shortsamplingintervalsmayaffect
communicationperformance.
Relatedinformation
CommunicationPerformance
9.1.1 AddingaTrendViewerObject
A trend viewer object is added to a screen from the Objects group on the Home
ribbon tab.
Settings for the trendviewer ob
ject are available from the General ribbon tab while
the trend viewer object is sele
cted:
CurvesGroup
Trend viewer curves are defined using the Edit Curves control.
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