Technical Reference Manual - InduSoft

Alarms, Events, and Trends
DATA SOURCES DIALOG
Accessing the dialog
To access the Data Sources dialog for a specific Trend Control screen object, first access the Object Properties
dialog for that screen object and then click Data Sources.
The dialog in detail
Data Sources dialog
The data source defines the location of the values from the data point(s) associated with it. Many points can
share the same data source — you do not need to create one data source for each data point.
The data source tag is available by default to the Trend Control object. You can add additional data sources
with the New button. The name you enter will be used as an alias to link the data points to this new data
source.
The other fields in this dialog allow you to edit the data source settings:
• Source Type: Select the source type of the location of the data point values.
• X-Axis: Enter the name of the field (column) from the data source that holds the X axis data.
• Max. Buffer: The maximum amount of data (in bytes) that will be held in runtime memory.
• Load Progress: The tag in this field will receive a real value (0-100) that represents the percentage of the Data
Source load progress.
• Sort: This option is useful for plotting data from a Text file. When enabled (checked), it sorts the data and
shows the Cursor column value until the Max. Buffer is filled. When disabled (unchecked), the data are not
sorted and the Cursor column value is not shown.
• Keep Open: This option keeps the data source open as long as the screen that contains the Trend Control
object is open. This improves the performance of the runtime project, but keeping the data source open
may cause other problems like database connection errors (when Source Type is Database) and file write
conflicts (when Source Type is Batch or Text File). To close the data source after the data has been loaded, clear
(uncheck) this option.
• Data Source Settings: Click to define the settings for the selected Source Type.
The following table summarizes the settings for each Source Type:
Data Source Type Description X-Axis field Data Source Settings
Batch
Batch generated by the Trend
task of IWS
Disabled. The X-Axis data will
be retrieved automatically on
the correct position from the
proprietary Batch file generated
by IWS.
Enter the data point values in Batch Name for their retrieval. You
can configure a tag between curly brackets in this field to change
this setting dynamically during runtime.
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