Siemens SINUMERIK 828D Programming Manual page 301

At the same time as the curvature is being adapted to the circular path of the full circle,
traversing is performed from Z60 to the plane of the circle Z0:
Figure 10-2
Further information
Approach/Retraction with NORM
1. Approach:
Fundamentals
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
10.2 Contour approach and retraction (NORM, KONT, KONTC, KONTT)
3D representation.
If is activated, the tool will move directly to the compensated start position along a
NORM
straight line (irrespective of the preset approach angle programmed for the travel
movement) and is positioned perpendicular to the path tangent at the starting point.
Tool radius compensation
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