Reply To: Sanity Check

AdminFred Graham
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Hi Jim, there is certainly more than one way to approach this. I don’t see any problem doing what you’re suggesting, of course modelling off-line and testing it would be the ideal approach.

I’ve accomplished this too using the CVInitReq and CVInitValue as demonstrated in some of my PID videos on YouTube. You can have a “Process_Stopped” bit driven by all your fault logic and then have CV driven to the desired position (in your case 0 or off) by writing that value to CVInitValue.

When in Override mode the instruction does not compute the change in CV (which is what you want), instead, CV = CVOverride, regardless of the control mode. Since it sounds like you want to handle all of this programmatically your approach should be fine, my only concern is if the duration the system is “down” is too long, handling the restart programmatically could create some other problems? I don’t know the dynamics of the process but just wanted to point that out and maybe something to consider.

Have you tried to implement and it’s not working as expected?