478 Rockwell Automation Publication 1756-RM006K-EN-P - November 2018
Execution
Ladder Diagram
Condition Action Taken
Prescan The rung-condition-out is set to false.
Rung-condition-in is false The rung-condition-out is set to false.
Rung-condition-in is true The instruction executes.
The rung-condition-out is set to true.
Scan of structured text No action taken
Instruction execution The instruction commands the Equipment Sequence to the specified state.
Postscan The rung-condition-out is set to false.
Structured Text
Condition Action Taken
Prescan No action taken.
Rung-condition-in is false No action taken.
Rung-condition-in is true No action taken.
Scan of structured text In structured text, instructions execute each time they are scanned. To
limit the scan of an instruction, use a qualifier of an SFC action or a
structured text construct that includes a condition, such as if, then, or else.
Instruction execution The instruction commands the Equipment Sequence to the specified state.
The SOVR instruction sends one of the following commands: HOLD, STOP,
or ABORT.
Postscan No action taken.
See also
Guidelines for SOVR instructions on page 480
Result codes for SOVR instructions on page 484
SOVR instruction examples on page 488
When should I use an SOVR instruction instead of an SCMD instruction?
on page 489