#### Target Group Chart

This chart type requires the selection of Features. If the Feature Variable list is displayed in the side bar, this chart icon will be grayed out. Access the Feature list in the side bar, and apply some features to the tabbed window to display this chart type.

The Target Group Chart plots the positions of several features. The center of the plot represents the nominal position of each point. The upper tolerance for each feature is used to draw the radius of the inner circle (or ellipse or rectangle, depending upon your tolerancing configuration), so that the radius is equal to the tolerance. Out of tolerance is determined by whether or not the points lie outside of the first (innermost) circle, ellipse, or rectangle. Note that the tolerances may be different for the features; however, the ratio of the X to the Y tolerances must be identical or the system cannot create the plot.

The Target Plot’s layout allows you to compare the plotted points to the nominals and tolerances. You can select to show up to six specification limits, which are drawn as additional circles, ellipses, or rectangles outside the innermost one. The radius of each outer circle, ellipse or rectangle is incremented by one tolerance value. The deviations of the measured values are then plotted and labeled with letters, and the centroid of the measured points is calculated and shown as the intersection point of two dashed lines. Datapage+ reports the centroid and tolerance values differently depending upon whether the tolerances for all features are the same or not. If the tolerances are not identical, the average tolerance and a weighted centroid value are reported. See Calculations of Centroid Values for Group Target Plots.

Sample Chart

See also:

- Chart Display - Target Plot

- Target Individual Chart

- True Position Tolerancing

- Elliptical Tolerancing

- Rectangular Tolerancing

- Troubleshooting Problems

Important: True Position Tolerancing is the default tolerance for the first Target Plot you create. See "Chart Display - Target Plot" for information on changing the tolerancing. If you are creating your first Target Plot and the T. variable required for True Position Tolerancing does not exist in the database, you can just create a plot anyway (it will display “No Valid Data”), and set your configuration later, or you can use the Data Editor tab to create or rename the .T variable, and then create the plot. See "Data Editor Tab".