Siemens sinumerik 840D sl Function Manual page 538

Consequently, if the compensation vector changes due to the workpiece contour, the
interpolation of the direction axes is included in the path interpolation of the geometry axes.
In order to minimize the impact of the direction axes on the path interpolation, it is
recommended to configure the dynamic response of the direction axes at least equal to or
greater (by a factor of approx. 10) than the dynamic response of the geometry axes.
In the case of a re-orientation (rotation) of the compensation vector, it is also necessary to
note the ratio between the programmed traversing path and the configured dynamic
response of the direction axes. The ratio should be chosen such that the programmed
traversing path is not traversed in one or a small number of interpolation cycles, due to the
dynamic response of the axis. This causes heavy loads on the machine and, in certain
circumstances, may trigger axial alarms and abort part program execution.
Example
Rotation of the compensation vector and thus the machining head through 90°:
• Initial orientation: Parallel to coordinate axis X
• Target orientation: Parallel to coordinate axis Y
• [1, 0, 0] → [0, 1, 0]
• [100, 0, 0] → [0, 100, 0]
Rotation of the workpiece coordinate system
As described above, the compensation vector always refers to the basic coordinate system
(machine coordinate system). If the workpiece coordinate system (rotation, mirroring) is
transformed to machine a workpiece in such a way that the coordinate axes of both
coordinate systems are no longer parallel with the same orientation, a corresponding
transformation must be carried out for the compensation vector.
Caution
If the workpiece coordinate system is transformed such that the coordinate axes of the basic
and workpiece coordinate systems are no longer parallel with the same orientation, it is the
sole responsibility of the user to ensure that an appropriate transformation of the
compensation vector is carried out.
Special functions: Clearance Control (TE1)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Bad programming of re-orientation:
Good programming of re-orientation:
Detailed description
2.6 Programming
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