Siemens SINUMERIK 840DE Programming Manual page 101

Turning:
For calculating the direction of rotation, the controller requires the specification of the
working plane, refer to circular interpolation G2/G3.
Machining on inclined planes
By turning the coordinate system withROT (see Section "Coordinate system offset") you
position the coordinate axes on the inclined surface. The working planes rotate accordingly.
Tool length compensation in inclined planes
The tool length compensation generally always refers to the fixed, non-rotated working
plane.
Milling:
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
3.7 Selection of working plane (G17 to G19)
Positional Data
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