Siemens SINUMERIK 840DE sl Function Manual page 159

the pole, a deviation is made from the specified path because the interpolation runs exactly
through the pole point.
● MD24530 $MC_TRAFO5_NON_POLE_LIMIT_1
● MD24630 $MC_TRAFO5_NON_POLE_LIMIT_2
As a result, the position at the end point of the fourth axis (pole axis) deviates from the
programmed value.
This machine data specifies the angle by which the pole axis may deviate from the programmed
value with a 5-axis transformation if a switchover is made from the programmed interpolation
to interpolation through the pole point. In the case of a greater deviation, an error message is
output and the interpolation is not executed.
Figure 3-13
Behavior during large circle interpolation at pole position
The following machine data can be used to set the response for large circle interpolation in pole
position as follows:
MD21108 $MC_POLE_ORI_MODE
Does not define the treatment of changes in orientation during large circle interpolation unless
the starting orientation is equal to the pole orientation or approximates to it and the end
orientation of the block is outside the tolerance circle defined in the following machine data.
● MD24530 $MC_TRAFO5_NON_POLE_LIMIT_1
● MD24630 $MC_TRAFO5_NON_POLE_LIMIT_2
The position of the polar axis is arbitrary in the polar position. For the large circle interpolation,
however, a specified orientation is required for this axis.
The following machine data is coded decimally.
MD21108 $MC_POLE_ORI_MODE
Transformations
Function Manual, 06/2019, A5E47435470B AA
5-axis transformation; orientation path in pole vicinity. Example for machine type 1: 2-axis
swivel head with rotary axis RA 1 (4th axis of transformation) and rotary axis RA 2 (5th axis
of transformation)
F2: Multi-axis transformations
3.2 5-axis transformation
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