ISO Limits and Fits

The ISO Limits and Fits area in the Feature Location dialog box (Insert | Dimension | Location) allows you to apply ISO standardized tolerances to the diameter of circular features. When a tolerance class and grade have been selected, PC-DMIS will look up the appropriate tolerances for the diameter of a cylinder or circle from the International Organization for Standardization’s tables of Limits and Fits. These tables define the tolerances for various design classes and grades of diameters.

Although PC-DMIS allows the calculation of ISO tolerances in English (Inch) and metric (mm) units, they are only defined by ISO to be applied with metric (mm) units. Also, because these tables use various classes and grades of diameters, cylinders and circles are the only appropriate features for this option. If no nominal diameter is entered, PC-DMIS uses the feature’s nominal diameter for the tolerance calculations.

More:

Nominal Size

Tolerance Class

Tolerance Grade