Do Not Start Partial Infeed Too Early - Siemens SINUMERIK 840D sl Function Manual

P5: Oscillation - only 840D sl
12.3 Oscillation controlled by synchronized actions
12.3.6

Do not start partial infeed too early

Function
The functions described above prevent any infeed movement outside the reversal point or
the reversal point range. On completion of an infeed movement, however, restart of the next
partial infeed must be prevented.
Application
A channel-specific flag is used for this purpose. This flag is set at the end of the partial infeed
(partial distance-to-go == 0) and is deleted when the axis leaves the reversal point range.
The next infeed movement is then prevented by a synchronized action.
Programming
WHENEVER $AA_DTEPW[infeed axis] == 0
DO $AC_MARKER[index]=1
and, for instance, for reversal point 1:
WHENEVER $AA_IM[Z] <> $SA_OSCILL_REVERSE_POS1[Z]
DO $AC_MARKER[Index]=0
WHENEVER $AC_MARKER[index]==1
DO $AA_OVR[infeed axis]=0
Explanation of system variables:
$AA_DTEPW[infeed axis]: axial remaining travel distance for the infeed axis in the MCS:
Path distance of the infeed axis
$AC_MARKER[index]: Channel-specific marker with index
$AA_IM[oscillation axis]: Current position of oscillation axis
$SA_OSCILL_REVERSE_POS1[oscillation axis]: Reversal point 1 of the oscillation axis
$AA_OVR[infeed axis]: Axial override for infeed axis
Explanation of key words:
WHENEVER ... DO ... Whenever condition is fulfilled, then ...
830
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Extended Functions