Siemens Sinumerik 840D sl Programming Manual page 257

Meaning
NORM:
KONT:
KONTC:
KONTT:
Note
Only G1 blocks are permissible as original approach/retraction blocks for KONTC and KONTT.
The control replaces these with polynomials for the appropriate approach/retract path.
Supplementary conditions
KONTT and KONTC are not available in 3D variants of tool radius compensation (CUT3DC,
CUT3DCC, CUT3DF). If they are programmed, the control switches internally to NORM without
an error message.
Example
KONTC
The full circle is approached beginning at the circle center point. The direction and curvature
radius at the block end point of the approach block are identical to the values of the next circle.
Infeed takes place in the Z direction in both approach/retraction blocks simultaneously. The
figure below shows the perpendicular projection of the tool path.
Figure 11-1
Fundamentals
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
11.2 Approaching and leaving contour (NORM, KONT, KONTC, KONTT)
Activate direct approach/retraction to/from a straight line.
The tool is oriented perpendicular to the contour point.
Activate approach/retraction with travel around the starting/end point according to the
programmed corner behavior G450 or G451.
Activate approach/retraction with constant curvature.
Activate approach/retraction with constant tangent.
Perpendicular projection
Tool radius compensation
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