To Modify Tolerances of a Driven Dimension
Manipulation of the tolerances for a driven dimension is similar to that of the tolerances of regular dimensions. You can change the tolerance values and modify their format. A difference is that you can not set an upper or lower limit of the driven dimension, because the nominal value of the driven dimension is not changeable. The system calculates the limits based on the measurement between the two reference entities and the tolerance values.
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Make sure your environment is set to display dimension tolerances. On the Options dialog box, click Entity Display, and select the Show dimension tolerances check box and click OK.
1. Select a driven dimension in the Model Tree or on the screen. The Dimension tab appears.
2. To change the tolerance format, select one of the options from the Tolerance list:
Nominal
Basic
Limits
Plus-Minus
Symmetric
When you select Symmetric, the toleranceSuperscript is available in the Tolerance group.