Chapter 14 Sequential Function Chart The following table provides Step member categorization. Take executing Step member X in SFC for example, when users want to trigger the contact to ON for POU in ladder programming once Step execution starts, the programs are written in the following ways. By using appears and provides POU name options for SFC program then click the name. normally-open contact of POU in ladder program, click on top of the normally-open contact, a drop-down list appears, then select the name.
After clicking the POU name for SFC program, right-click the mouse and a drop-down list with POU Step name 14-23 Write X X X X X X Category Member Description Read Step X When executing Step, the SFC parameter property is V ON；this parameter property can replace previous S device. done When Step Property T (the current time spent V executing Step) >= Step property timePreset and the value is ON counter When Step property X changes from OFF to ON, V parameter property count adds 1 timePres Determines the time for Step property done changes from OFF to ON (unit: ms, data length: DWORD) V et maxTime Record the maximum time of Step property T (unit: ms, V data length:
DWORD) T The time spent executing Step (unit: ms, data length: DWORD) V