Siemens sinumerik 840D sl Function Manual page 68

Detailed description
2.8 Orientation
Please note that if all three vector components are zero (because they have been set
explicitly so or not specified at all), the basic orientation is not defined by data in the
TRAORI(...) call, but by one of the methods described below.
If a basic orientation is defined by the above method, it cannot be altered while a
transformation is active. The orientation can be changed only by selecting the transformation
again.
Via the orientation of the active tool
For 2.:
The basic orientation is determined by the tool
• if it has not been defined through specification of a direction vector in the transformation
• and if a tool is already active.
The orientation of a tool is dependent on the selected plane. It is parallel to Z at G17, parallel
to Y at G18 and parallel to X at G19.
It can be modified arbitrarily by orientable toolholders, see:
References: /FB1/Function Manual Basic Functions; Tool Offset; Orientable Tool Holders
(W1)
If the tool is changed when a transformation is active, the basic orientation is also updated.
The same applies if the orientation of a tool changes as the result of a change in plane
(plane changes are equivalent to tool changes, as they also alter the assignment between
tool length components and individual axes).
If the tool is de-selected, thereby cancelling the definition of tool orientation, the basic
orientation programmed in machine data becomes operative.
Via machine data
For 3.:
If the basic orientation is not defined by either of the two variants described above, it is
specified with reference to the following machine data.
$MC_TRAFO5_BASE_ORIENT_n (basic tool orientation)
This machine data must not be set to a zero vector or else an alarm will be generated during
control run-up when a transformation is active.
If a basic orientation is programmed in machine data $MC_TRAFO5_BASE_ORIENT_n
when a transformation is active and a tool is subsequently activated, the basic orientation is
re-defined by the tool.
Note
The range of settable orientations depends on the directions of the rotary axes involved and
the basic orientation. The rotary axes must be mutually perpendicular if all possible
orientations are to be used. If this condition is not met, "dead" ranges will occur.
62
call
Special functions: 3-Axis to 5-Axis Transformation (F2)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0