Points dialog

The Points dialog is used to configure the data points for a Trend Control screen object. The value of each data point is represented as a pen in the trend display. You can dynamically change which data points are visible during runtime, regardless of how many data points are associated with the screen object.

Accessing the dialog

To access the Points dialog for a specific Trend Control screen object, first access the Object Properties dialog for that screen object and then click Points.

The dialog in detail

Figure 1. Points dialog
Object Properties: Trend Control dialog

The following table summarizes the properties of each data point:
Column Name Description
Point A unique ID number for the point, which is assigned automatically when the point is created in this interface.
Label The label associated with the Point can be displayed on the Legend, during runtime, providing a short reference to the user for each Point.
Color The color of the pen usedColor of the pen used to draw the values of the Point on the Trend Control object.
Data Source The data source for this point. Tag is available by default, but all other sources must be configured in the Data Sources dialog.
Tag/Field The meaning of this parameter depends on the Data Source type associated with the data point:
  • Tag: Type the name of the tag with values to display. If the tag is configured in the Trend task, the history data is automatically retrieved; otherwise, only the online values are displayed.
  • Batch: Type the name of the tag with values to be retrieved from the Batch History file generated by the Trend Task, and displayed on the object.
  • Database: Type the name of the field (column) in the SQL Relational Database that holds the data Point values.
  • Text File: Type the number of the column that holds the Point values. The number 0 refers to the first column, 1 refers to the second column, and so on.
Min / Max The scale of the Y-axis for this point. This overrides the default scale that is set in the Axes dialog.
Note: The Min and Max properties can hold real numeric values up to six decimal places. If you need more precision than that, then you must configure the Min and Max properties with Real tags and then store the values in those tags.
Style The line and marker styles for this point; click the browse button button to open the Pen Style dialog.
Options Additional options for this point; click the browse button button to open the Options dialog.
Hide Tag trigger — when the value is TRUE, the data point is hidden in the trend display.