Siemens SINUMERIK 840D sl Function Manual page 421

Frame
A frame change with G91 (incremental dimension) is not specially treated for active
transformation. The path to be traversed is evaluated in the workpiece coordinate system of
the new frame - regardless of which frame was active in the previous block.
A rotary axis offset can, for example, be entered by compensating the inclined position of a
workpiece can be considered using a frame or as offset of the rotary axis.
The following setting is required for the axial complete frame of the rotary axis to act in the
transformation:
$MC_TRACYL_ROT_AX_FRAME_<t> = 1
Note
Changes in the axis assignments are converted every time the transformation is selected or
deselected.
References:
Function Manual Basic Functions; "Co-ordinate Systems, Frames" (K2)
Function restriction for transformation axes
The axes involved on the cylinder surface transformation must not be used for the following
functions:
● Positioning axis
● Oscillating axis
● Preset axis
● Fixed point approach G75
● Reference point approach G74
Manual traversal in JOG
When generated cylinder surface transformation with groove side compensation
($MC_TRAFO_TYPE = 513) is active in JOG mode, it must be noted that the axes are traversed
depending on the preceding status in AUTOMATIC. For active groove side compensation, the
axes so move differently than for deselected compensation. The part program can therefore
be continued (REPOS) after a part program interruption.
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
7.2 TRACYL cylinder surface transformation (option)
M1: Kinematic transformation
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