Constraints - Siemens SINUMERIK 840D sl Function Manual

M1: Kinematic transformation
7.2 TRANSMIT (option)
7.2.10

Constraints

Look Ahead
All functions requiring Look Ahead (traversal through pole, Look Ahead) work satisfactorily
only if the relevant axis motions can be calculated exactly in advance. With TRANSMIT, this
applies to the rotary axis and the linear axis perpendicular to it. If one of these axes is the
positioning axis, then the Look Ahead function is deactivated by alarm 10912 and the
conventional online velocity check activated instead.
Selection of method
The user is responsible for making the optimum choice of "Traversal through pole" or
"Rotation around pole".
Several pole traversals
A block can traverse the pole any number of times (e.g. programming of a helix with several
turns). The parts program block is subdivided into a corresponding number of sub-blocks.
Analogously, blocks which rotate several times around the pole are likewise divided into sub-
blocks.
Rotary axis as modulo axis
The rotary axis can be a modulo rotary axis. However, this is not a mandatory requirement
as was the case in SW 2 and 3. The relevant restrictions applying in SW 2 and 3 have been
eliminated in SW 4.
Rotary axis as spindle
If the rotary axis without transformation is used as a spindle, it must be switched to position-
controlled mode with SPOS before the transformation is selected.
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Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Extended Functions