Lenze PLC Designer PLC Designer (R3-1) - Manual (Page 739)

L-force | PLC Designer
General Editors

DMS 4.1 EN 03/2011 TD29 737
Symbol Element name / Example Description
Abb. 408 Example of an action written in ST
Abb. 409 IEC conforming step action list associated to
a step
Each action box in the first column shows
the qualifier and in the second the action
name.
There are the following types of actions:
1. IEC conforming step action ("IEC action"):
This is an action according to standard IEC1131-3
which will be processed according to its qualifier
when the step has got active and a second time
when it has got deactivated. In case of assigning
multiple actions to a step (action list) the actions
will be executed from up to down.
• Different qualifiers can be used for IEC step
actions in contrast to a "normal" step action.
• A further difference to the "normal" step
actions is that each IEC step action is provided
with a control flag, which allows to make sure
that - even if the action is called also by
another step - the action will get executed
always only once at a time. This is not
guaranteed with the normal step actions.
• An IEC step action is represented by a bipartite
box, connected to the right of a step via a
connection line. In the left part it shows the
action qualifier, in the right part the action
name. Both can be edited inline.
• IEC step actions get associated to a step via the
'Insert action association (after)' command.
One or multiple actions can be associated to a
step. The position of the new action depends
on the current cursor position and the
command. The actions must be available in the
project and be inserted with a unique action
name (for example plc_prg.a1).