Siemens SINUMERIK 840D sl Function Manual page 107

Reference point at the tool
Taking into account the tool data (tool length and tool radius) and therefore the reference point
at the tool when monitoring the working area limitation depends on the status of the
transformation in the channel:
● Transformation inactive
Without transformations during traversing motion with an active tool the position of the tool
tip P is monitored, i.e. during the monitoring the tool length is considered automatically.
Consideration of the tool radius must be activated separately:
MD21020 $MC_WORKAREA_WITH_TOOL_RADIUS (Consideration of the tool radius in
the working area limitation)
● Transformation active
In the case of certain transformations the monitoring of the working area limitation may
differ from the behavior without transformation:
– The tool length is a component of the transformation
– Transformation with change in orientation:
Response
Automatic operating modes
● With / without transformation
The parts program block with a programmed traversing motion that would lead to
overrunning of the working area limits is not executed.
● With superimposed motion
The axis, which would violate the working area limitation due to a superimposed motion, is
braked with maximum acceleration and without jerk limits (BRISK), and will come to a stop
in the position of the working area limitation. Other axes involved in the movement are
braked according to current acceleration behavior (e.g. SOFT). The path correlation may
be lost due to different braking accelerations (contour violation).
Manual operating modes
● JOG with / without transformation
The axis is positioned at the working area limitation and then stopped.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
($MC_TRAFO_INCLUDES_TOOL_X = TRUE):
In this case the tool length is not considered, i.e. the monitoring refers to the tool carrier
reference point.
In the case of transformations with changes in orientation, monitoring is always based
on the tool center point. MD21020 has no influence.
Note
The machine data $MC_TRAFO_INCLUDES_TOOL_... is analyzed only in certain
transformations. Condition for a possible evaluation is that the orientation of the tool
with respect to the base coordinate system cannot be changed by the transformation.
With standard transformations, the condition is only fulfilled for the "inclined axis" type
of transformation.
A3: Axis Monitoring, Protection Zones
3.2 Axis monitoring functions
107