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Command Driven SFC HELP

I have a command driven SFC that has five different commands that run different valve position sequences, is it possible to write a 6th one that when activated will stop the others from running and then execute the sequence in this command, ie if I have executed any of the sequence 1-5 and this is running through to position certain valves I would like to press a button and this sequence stop and active a close all valves sequence (Sequence 6)?

If not am I best moving all the code to a PLM with command driven run logic?

GaryL

• 18 Jul 2019 10:03 AM
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3 Replies

• Matt Stoner

  

  • 18 Jul 2019 12:10 PM

  Yes this is possible, just add the new command to the named set after the current last command and if it is DeltaV Equipment Module it will automatically create what is needed. If it isn't a DeltaV Equipment Module you would have to manually add the items needed (SFC Composite named in the proper format, any parameters needed i.e. ENABLED).

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• GaryL

  

  • 19 Jul 2019 10:38 AM

  In reply to Matt Stoner:

  Thanks Matt, I have added the named set and created the code in the command driven SFC (I didn't go down the PLM route) how can I get the new code to run when there is already and SFC running/not completed (is this possible)?

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• Matt Stoner

  

  • 19 Jul 2019 11:35 AM

  In reply to GaryL:

  Unfortunately the SFC/Command EM doesn't support the download of it running and return/continue to run. You will need to find an opportunity that you can download the EM and then set the A_COMMAND to run that same command again (be careful that the A_COMMAND isn't pre-configured with a COMMAND as it would immediately start to execute on download). You may have to also manually set any parameters to have the command properly execute (i.e. First Pass Flag, Task Pointer, etc) and return where it currently is before you set the A_COMMAND if you can't find the opportunity to do this while it would be in a completed command. If you don't manually set then the command will most likely re-execute the whole command again (this may be not an issue or very bad depending on what the EM does).

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