The Perpendicular to Centerline check box in the Position dialog box (Insert | Dimension | Position) determines whether PC-DMIS calculates the deviation perpendicular to the feature's theoretical centerline or perpendicular to the direct X, Y, and Z values.
If marked, PC-DMIS calculates the deviation perpendicular to the feature's theoretical centerline, ignoring any deviation in the direction of the centerline.
If not marked, PC-DMIS calculates the deviation perpendicular to the X, Y, and Z values.
This check box is especially useful with sheetmetal points which may have approach vectors not oriented along the X, Y, or Z axis. This check box will allow the deviation to be found perpendicular to the approach vector.