Siemens SINUMERIK 840D sl Programming Manual page 285

Description
Accuracy
You can only compress NC blocks if you allow the contour to deviate from the programmed
contour. You can set the maximum deviation as a compressor tolerance in the setting data.
The higher the tolerances, the more blocks can be compressed.
Axis accuracy
For each axis, the compressor creates a spline curve, which deviates from the programmed
end points of each axis by no more than the tolerance set with the axial machine data.
Contour accuracy
The maximum geometrical contour deviations (geometry axes) and the tool orientation are
monitored. This is achieved using the setting data for:
1. Maximum tolerance for the contour
2. Maximum angular displacement for the tool orientation
3. Maximum angular displacement for the angle of rotation THEATA of the tool
You can use the channel-specific MD 20482 COMPRESSOR_MODE to set tolerance
specifications:
0: Axis accuracy: Axial tolerances for all axes (geometry axes and orientation axes)
1: Contour accuracy: Specification of the contour tolerance (1.), tolerance for the orientation
using axial tolerances (a.)
2: Specification of the maximum angular displacement for tool orientation (2.), tolerance for
the contour using axial tolerances (a.)
3: Specification of the contour tolerance with (1.) and specification of the maximum angular
displacement for tool orientation with (2.)
It is only possible to specify a maximum angular displacement for tool orientation if an
orientation transformation (TRAORI) is active.
Job planning
Programming Manual, 03/2006 Edition, 6FC5398-2BP10-1BA0
7.6 Compression of the orientation COMPON (A..., B..., C..., THETA)
(only available on 6-axis machines)
Transformations
7-47