Siemens SINUMERIK 840Di Function Manual page 565

Block search type 2
In "Block search with calculation at contour", the ASUB must be exited with the REPOSA
command. The axes are then automatically moved to the collected block search position.
$P_EP then also returns to this value.
Block search type 4
After "Block search with calculation at block end point", automatic repositioning is not
performed by the REPOS part program command between "Last action block active" and
continuation of part program processing via an NC Start. The start point of the approach
movement is the current axis position on NC Start; the end point results from the processing
of the part program.
No approach motion is generated by the system with "Block search with calculation at block
end point". $P_EP thus returns the position at which the axes were positioned by the ASUB
or in JOG after the ASUB has been exited.
PLC actions after block search
To enable activation of PLC actions after a block search, e.g., starting of ASUBs or FCs at a
defined position, interface signal:
DB21... DB32.6 (last action block active) is used.
This means that all action blocks are processed and that actions are possible by the PLC
(ASUB, FC) or the operator (overstoring, mode change after JOG/REPOS). This allows the
PLC to perform another tool change, for example, before the start of the movement.
By default, alarm 10208 is output at this moment to notify the operator that an NC Start is
needed to continue program execution.
Alarm 10208 sets the following interface signals:
DB21, ... DBX36.7 (NCK alarm with processing stop)
DB21, ... DBX36.6 (channel-specific NCK alarm is present)
MD11450
Machine data:
MD11450 $MN_SEARCH_RUN_MODE
allows you to set a different response.
If MD11450 = 1, alarm 10208 is not output until the
PLC sets interface signal:
DB21, ... DBX1.6 (PLC action complete).
Mode Group, Channel, Program Operation, Reset Response (K1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Detailed Description
2.5 Block search
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