Lenze DDS v2.3 - Manual (Page 55)

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DDS EN 2.3
4.4.10 Alternative branch
Two or more branches in SFC may be defined as alternative branches.
•
Every alternative branch must start and end with a transition.
•
Alternative branches may include parallel branches and further alternative branches.
•
An alternative branch starts with a horizontal line (alternative start) and ends with a horizontal
line (alternative end) or a jump.
•
If the step before the alternative start line is active, the first transition of every alternative
branch will be evaluated from left to right. The first transition from the left, whose transition
condition is TRUE, is opened and the subsequent steps are activated.
4.4.11 Parallel branch
Two or more branches in SFC may be defined as parallel branches.
•
Every parallel branch must start and end with a step.
•
Parallel branches may include alternative branches or further parallel branches.
•
A parallel branch starts with a double line (parallel start) and ends with a double line
(parallel end) or a jump and can be assigned a jump label.
•
If the step before the parallel start line is active, and the transition condition after this step is
TRUE
, the first steps of all parallel branches will become active. These branches will then all
be processed in parallel.
•
The step after the parallel end line will become active if all preceding steps are active and the
transition condition before this step is TRUE.
4.4.12 Jump
A jump is a connection to the step whose name appears underneath the jump icon.
Jumps are necessary because upward or intersecting connections are not allowed.
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