Siemens SIMATIC FM 453, Manual

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FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
The program is processed to the end point of the target block, including tool
offset. M commands and dwell times are output and the traversing move-
ments are suppressed.
When processing traversing programs with a forward block search, there are
a number of special cases:
S
The external forward block search (G50) is not executed.
S
Continuous travel with functions to set (G88, 89) or delete (G87) an ac-
tual value on-the-fly is not executed.
S
The blocks under G50, G87, G88, G89 (in the processing direction)
should contain a path in absolute coordinates.
Similar to block search forward
Automatic block search forward/backward means that, after the interruption
of an active automatic program (by an operating mode change), you can con-
tinue execution from this point of interruption in the appropriate direction of
processing.
With forward block search, the interrupted program must previously have
been going in the forward direction.
With block search in reverse, the interrupted program must previously have
been going in the reverse direction.
The command for automatic forward or reverse block search is evaluated in
the FM 453 at Start, and a forward or reverse search to the interruption point
is executed. Positioning to the interruption point takes place (if positioning
has taken place previously in some other mode), and then the interrupted
block is processed, including any required output.
Block Search
Forward
Block
Search Backward
Automatic Block
Search Forward/
Backward
Description of Functions