Siemens SINUMERIK 840D sl Function Manual page 39

Dynamic response
Involutes that begin or end on the base circle have an infinite curvature at this point. To
ensure that the velocity is adequately limited at this point when tool-radius compensation is
active, without reducing it too far at other points, the "Velocity limitation profile" function must
be activated:
MD28530 $MC_MM_PATH_VELO_SEGMENTS > 1 (number of memory elements for
limiting the path velocity)
A setting of 5 is recommended. This setting need not be made if only involute sections are
used, which have radii of curvature that change over a relatively small area.
2.2.3 Activate DEFAULT memory
GUD start values
The DEF... / REDEF... NC commands can be used to assign default settings to global user
data (GUD). These default settings must be permanently stored in the system if they are to
be available after certain system states (e.g. RESET).
The memory space for this is taken from the memory area that was assigned via the
machine data:
MD18150 $MM_GUD_VALUES_MEM (number of additional parameters according to
MD18170)
The setting for activating the stored default values is made in machine data:
MD11270 $MN_DEFAULT_VALUES_MEM_MASK (activation default values for NC
language elements)
References:
/FB1/Function Manual Basic functions; S7: "Memory Configuration"
/PGA/ Programming Guide Advanced
Basic logic functions: Various NC/PLC interface signals and functions (A2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Detailed description
2.2 Functions
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