Siemens SINUMERIK 840D sl Function Manual page 501

Special features relating to pole traversal
The method of pole traversal along the linear axis may be applied in the AUTOMATIC and
JOG modes.
System response:
Table 7-1
Operating mode
AUTOMATIC
JOG
Special features relating to rotation in pole
Precondition: This method is only effective in the AUTOMATIC mode.
MD24911 $MC_TRANSMIT_POLE_SIDE_FIX_1 = 1 or 2
MD24951 $MC_TRANSMIT_POLE_SIDE_FIX_2 = 1 or 2
Value: 1 Linear axis remains within positive traversing range
Value: 2 Linear axis remains within negative traversing range
In the case of a contour that would require the pole to be traversed along the tool center
point path, the following three steps are taken to prevent the linear axis from traversing in
ranges beyond the turning center:
Step
1
2
3
In JOG mode, the motion stops in the pole. In this mode, the axis may exit from the pole only
along the path tangent on which it approached the pole. All other motion instructions would
require a step change in the rotary axis position or a large machine motion in the cases of
minimum motion instructions. They are rejected with alarm 21619.
Extended Functions
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Traversal of pole along the linear axis
State
All axes involved in the
transformation are moved
synchronously. TRANSMIT active.
Not all axes involved in the
transformation are traversed
synchronously (e.g. position axis).
TRANSMIT not active
An applied DRF (external zero
offset) does not interfere with the
operation. Servo errors may occur
close to the pole during application
of a DRF.
-
Action
Linear axis traverses into pole
Rotary axis turns through 180°, the other axes involved in the transformation
remain stationary.
Execution of remaining block. The linear axis now exits from the pole again.
Kinematic Transformation (M1)
7.2 TRANSMIT
Response
High-speed pole traversal
Traversal of pole at creep speed
Abortion of machining, alarm
Traversal of pole at creep speed
501