Siemens SINUMERIK 840D sl Function Manual page 393

Corner without pole traversal
Figure 7-4
Requirements:
AUTOMATIC mode,
MD24911 $MC_TRANSMIT_POLE_SIDE_FIX_1 = 1 or 2
or
MD24951 $MC_TRANSMIT_POLE_SIDE_FIX_2 = 1 or 2
The control system inserts a traversing block at the step change point. This block generates
the necessary rotation so that machining of the contour can continue on the same side of the
pole.
Transformation selection in pole
If the machining operation must continue from a position on the tool center path which
corresponds to the pole of the activated transformation, then an exit from the pole is specified
for the new transformation.
If
MD24911 $MC_TRANSMIT_POLE_SIDE_FIX_1 = 0
or
MD24951 $MC_TRANSMIT_POLE_SIDE_FIX_2 = 0
is set (pole transition), then a rotation as small as possible is generated at the beginning of the
block originating in the pole. Depending on this rotation, the axis then traverses either in front
of or behind the turning center.
For
MD24911 $MC_TRANSMIT_POLE_SIDE_FIX_1 = 1
or
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Machining on one pole side
M1: Kinematic transformation
7.1 TRANSMIT face end transformation (option)
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