Lenze PLC Designer PLC Designer (R2-x) - Manual (Page 71)

L-force | PLC Designer
What is What in PLC Designer

DMS 3.2 EN 02/2011 TD29 69
Note!
Regard also the implicit variables usable for scanning the status and time of steps
resp. actions.
Alternative branch
Two or more branches in SFC can be defined as alternative branches. Each alternative
branch must begin and end with a transition. Alternative branches can contain
parallel branches and other alternative branches. An alternative branch begins at a
horizontal line (alternative beginning) and ends at a horizontal line (alternative end)
or with a jump.
If the step which precedes the alternative beginning line is active, then the first
transition of each alternative branch is evaluated from left to right. The first transition
from the left whose transition condition has the value TRUE is opened and the
following steps are activated (see active step).
Parallel branch
Two or more branches in SFC can be defined as parallel branches. Each parallel branch
must begin and end with a step. Parallel branches can contain alternative branches or
other parallel branches. A parallel branch begins with a double line (parallel
beginning) and ends with a double line (parallel end) or with a jump. It can be
provided with a jump label.
If the parallel beginning line of the previous step is active and the transition condition
after this step has the value TRUE, then the first steps of all parallel branches become
active (see active step). These branches are now processed parallel to one another. The
step after the parallel end line becomes active when all previous steps are active and
the transition condition before this step produces the value TRUE.
Jump
A jump is a connection to the step whose name is indicated under the jump symbol.
Jumps are required because it is not allowed to create connections which lead upward
or cross each other.