Siemens SINUMERIK 840D sl Function Manual page 771

Figure 10-24 Frame on activation of a rotary table with TCARR
With kinematics of type M (tool and table are each rotary around one axis), the activation of a
toolholder with TCARR simultaneously produces a corresponding change in the effective tool
length (if a tool is active) and the work offset.
Rotations
Depending on the machining task, it is necessary to take into account not only a work offset
(whether as frame or as tool length) when using a rotary toolholder or table, but also a rotation.
However, the activation of an orientable toolholder never leads directly to a rotation of the
coordinate system.
If only the tool can be rotated, a frame can be defined for it using TOFRAME or TOROT.
With rotary tables (kinematics types P and M), activation with TCARR similarly does not lead
to an immediate rotation of the coordinate system, i.e. even though the zero point of the
coordinate system is offset relative to the machine, while remaining fixed relative to the zero
point of the workpiece, the orientation remains unchanged in space.
If the coordinate system needs to be fixed relative to the workpiece, i.e. not only offset relative
to the original position but also rotated according to the rotation of the table, then PAROT can
be used to activate such a rotation in a similar manner to the situation with a rotary tool.
With PAROT, the translations, scalings and mirroring in the active frame are retained, but the
rotation component is rotated by the rotation component of an orientable toolholder
corresponding to the table. The entire programmable frame including its rotation component
remains unchanged.
The rotation component that describes the rotation of the table is then either entered in the
system frame $PARTFR or in the basic frame parameterized with MD20184
$MC_TOCARR_BASE_FRAME_NUMBER:
$MC_MM_SYSTEM_FRAME_MASK, bit 2 = <value>
Value Meaning
1
0
As with the note made in the description of the table offset, the second alternative here is not
recommended for use with new systems.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Rotation component → $PARTFR
Rotation component → MD20184 $MC_TOCARR_BASE_FRAME_NUMBER
K2: Axis Types, Coordinate Systems, Frames
10.5 Frames
771