Siemens SINUMERIK 828D Programming Manual page 607

Significance
Activate axial leading value coupling:
...DO LEADON(FA, LA, NR,
OVW)
Deactivate axial leading value coupling:
...DO LEADOF(FA, LA)
... DO LEADOF(FA)
Activate access with synchronized actions RELEASE
The axis to be coupled is released for synchronized action access by invoking the RELEASE
function for the axis.
Example:
RELEASE (XKAN)
ID=1 every SR1==1 to LEADON(CACH,XKAN,1)
OVW=0 (default value) )
Without a resynchronization, no new curve table can be specified for an existing coupling.
A change of the curve table requires the previous deactivation of the existing coupling and a
reactivation with the changed curve table number. This causes a resynchronization of the
coupling.
Changing the curve table for an existing coupling using OVW=1
OVW=1
is performed. The following axis attempts as fast as possible to follow the position values
specified by the new curve table.
Example of on-the-fly parting
An extruded material which passes continuously through the operating area of a cutting tool
must be cut into parts of equal length.
X axis: Axis in which the extruded material moves. WCS
X1 axis: Machine axis of extruded material, MCS
Y axis: Axis in which cutting tool "tracks" the extruded material
It is assumed that the infeed and control of the cutting tool are controlled via the PLC. The
signals at the PLC interface can be evaluated to determine whether the extruded material
and cutting tool are synchronized.
Actions
Activate coupling,
Deactivate coupling,
Set actual values,
Job planning
Programming Manual, 07/2010, 6FC5398-2BP40-0BA0
can be used to specify a new curve table to an existing coupling. No resynchronization
LEADON
LEADOF
PRESETON
with:
FA: Following axis
LA: Leading axis
NR: Number of the stored curve table
OVW: Permit overwriting an existing coupling with changed
curve table
with:
FA: Following axis
LA: Leading axis, optional
Shortened form without specification of leading axis
Motion synchronous actions
10.4 Actions in synchronized actions
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