Siemens sinumerik 840D sl Function Manual page 694

Multiple input of tool orientation
According to DIN 66025, only one tool orientation may be programmed in a block, e.g. with
direction vectors:
N50 A3=1 B3=0 C3=0
If the tool orientation is input several times, e.g. with direction vectors and Euler angles:
N60 A3=1 B3=1 C3=1 A2=0 B2=1 C2=3
error message 12240 "Channel X block Y tool orientation xx defined more than once" is
displayed and the NC part program stops.
2.5.2 Orientation programming for 4-axis kinematics
Tool orientation for 4-axis kinematic
4-axis kinematics possess only one degree of freedom for orientation. When the orientation
is programmed using RPY angles, Euler angles or direction vectors, it is not generally
possible to guarantee that the specified orientation can be approached. If used at all, this
type of orientation programming is only suitable for certain types of kinematic, i.e. those
which feature an invariance in orientation angles relative to the basic axes. This is the case
for the SCARA kinematic, for example.
For this reason, orientation programming is only permitted via "orientation angle" A for 4-axis
kinematics. This angle corresponds to the RPY angle C according to the robotics definition,
i.e. one rotation about the Z-RO axis, as illustrated in Fig. "Orientation angle for 4-axis
kinematic".
Special functions: Handling Transformation Package (TE4)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Detailed description
2.5 Tool orientation
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