Siemens SINUMERIK 840D sl Function Manual page 1850

Detailed Description
2.4 Tool radius compensation 2D (TRC)
Modal G code (G340, G341), which defines the subdivision of the movement into individual blocks
from the start point to the end point
Figure 2-21
G340: The approach characteristic from P
G341: The approach characteristic from P
Note
Active, rotating frames are included in all cases where the position of the active plane G17 -
G19 (circle plane, helix axis, infeed movements perpendicular to the active plane) is relevant.
62
Sequence of the approach movement depending on G340/G341
If G247 or G347 is active (quadrant or semicircle) and start point P
machining plane defined by the end point P
Point P is not defined or coincides with P
2
The circle plane or the helix axis is determined by the plane, which is active in the
SAR block (G17 - G19), i.e., the projection of the start tangent is used by the
following block, instead of the tangent itself, to define the circle.
The movement from point P
velocity valid before the SAR block.
P and P are located within the machining plane, with the result that a circle is
3 4
always inserted instead of a helix with G247 or G347.
to P is shown in the figure.
0 4
, a helix is inserted instead of a circle.
4
.
3
to point P takes place along two straight lines at the
0 3
to P is shown in the figure.
0 4
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
is outside the
3
Basic logic functions: Tool Offset (W1)