Siemens sinumerik 840D sl Function Manual page 664

Adapting the zero points of the axes
MD62617
The mathematical zero points of axes are preset in the handling transformation package.
However, the mathematical zero point does not always correspond to the mechanical zero
point (calibration point) of axes. In order for the zero point of each axis to fit one another, the
difference between the mathematical zero point and the alignment point for each axis must
be entered in the following machine data:
MD62617 $MC_TRAFO6_MAMES[ ] (offset between mathematical and mechanical zero
points [axis no.]: 0...5)
The deviation to be entered corresponds to the difference between the mechanical zero
point and the mathematically positive direction of rotation of the axis.
Example
The example (Fig. "Matching mathematical and mechanical zero points") shows an
articulated arm kinematic. The mathematical zero point for axis 2 is 90º. This value must be
set for axis 2 in machine data:
MD62617 $MC_TRAFO6_MAMES[1] (offset between mathematical and mechanical zero
points)
Axis 3 is counted relative to axis 2 and therefore has a value of -90º as a mathematical zero
point.
Figure 2-11
Special functions: Handling Transformation Package (TE4)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Matching mathematical and mechanical zero points
2.3 Configuration of a kinematic transformation
Detailed description
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