The SFC's showed:
The SFC was in with a coil halfway submerged. codesys sfc example
"Fix it with a state machine," her manager said. The SFC's showed: The SFC was in with
She slammed her fist on the desk.
She went to the Action Definition for Step 20. Instead of putting Drain_Valve := FALSE in the step's exit action, she created a Global Action called Acid_Safety and set its qualifier to SD (Set Dominant—stays TRUE until explicitly reset). Three weeks later
Acid_Drain_Valve := FALSE; // Reset only when safe Emergency_Alerter := FALSE; Three weeks later, the line went live.
Then she wrote a parallel :