SFC vs python scripting for issuing control commands


  • Is there a reason we should consider SFC instead of just using Python scripting to loop through controls when the use case is to issue the same command to thousands of identical devices?
  • Does SFC allow for importing 61131-3 structured text, or is it only editable via charts? SFC would be nice if we could directly port in the 61131-3 from our plant automation controller, but we're not interested in recreating this code via charts.


One of the sub-systems within our client's plants often has dozens of physical controllers, thousands of individual devices managed wirelessly by those controllers, and tens of thousands of tags. We need to have plant-level control of the devices in this sub-system, a function that we have previously handled within our plant-level automation controller (SEL RTAC). But for this system this RTAC is mostly doing data concentration for a large number of tags without much interaction with the rest of the plant-level control.

On upcoming projects, we intend to connect directly to the physical controllers for this sub-system, and then need to issue controls directly to thousands of individual devices managed by them. We have not used the SFC module before since our plant control logic has historically been in automation controllers with Ignition serving only as a front end for issuing controls.

Any insight is appreciated!

1- I think the logic in SFC is much more complicated than what you can do yourself with Python scripting and if you can it will take a hit in performance.
2- As far as I know structured text code cannot be imported into Ignition. Structured text works directly with the variables created in the plc from the addresses of the sensors, etc.
Hope this helps.