Siemens SIMATIC PCS7 Manual page 123

4. Loop
Generation
Manipulation
Batch flexible , Manual
C79000-G7076-C650-02
A loop consists of a sequence (at least one AF or substructure) and one
feedback branch with a transition which brackets the sequence. Depending on
transitions 1 and 2 the contained structure is repeated several times. Only
self-contained structures (1 input and 1 output) can be repeated.
AF1
Figure 4-19 Representation of a loop
The transition of the feedback branch is processed temporally after the
transition of the main branch.
Feedback out of or into parallel or alternative branches is not possible.
When a loop is generated in an existing structure a sequences is generated
with an AF dummy and feedback branch together with a transition.
If you wish to configure an existing sequence (surrounded by a loop), you
will need to link one point on the connection line to the other with the lasso.
As with the parallel and alternative branches, a help line appears which
displays all possible locations for additions.
You can select the loop by clicking on the feedback line or enclosing it all
with the lasso.
To remove the loop (but without deleting its contents), you must select and
delete the transition in the feedback line.
Manipulation of the contents of the loop is identical to manipulation of the
contents of a sequence.
1 2
1
Recipe creation
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