Return PIDE to Manual after Override

[Spencerguenther]

Hi all,

I have a PIDE block (Logix5000) where I am introducing interlocks. I am using the ProgOverrideReq to set the CV to 0% (shut a control valve) when an interlock is activated. Once the interlock is clear, currently I need to set the controller mode back to manual by pressing the button on the HMI. I would like to have the controller set itself back to Manual mode by itself (while still holding the 0% output) after the interlock clears.
I have tried tying the interlock status to the OperManReq which successfully puts the controller back into Manual after an interlock, but then when I switch to Auto, I cannot switch back to Manual. I have tried using one shots to just pulse the OperManReq input, but still it hangs up when toggling between Man and Auto.

I feel that there is a simple solution, but the Function Blocks aren't my strong point...

Thanks

 

[Mispeld]

In my limited experience with PIDE, I used the '.ProgManualReq' and '.ProgAutoReq' inputs to the PIDE block for logic-based Auto/Manual transitions. Prior to the manual request, I use the '.CVProg' input, as a percent, to set the manual output. The auto transition should start from the last manual value via CVProg. At least that is how it works for me.

One note of caution is related to CV scaling. It can get confusing if the CV is not scaled as 0 to 100 percent. For example, '.CVInitValue' is in engineering units, whereas '.CVProg' is percent.

 

[Spencerguenther]

So I believe that would require remapping the default PIDE faceplate in the FTView ME to use the ProgXxxReq instead of the OperXxxReq and the CVOper to CVProg correct? I was hoping to avoid modifying the default PIDE controller faceplate so that I could just pull it up when starting a new project.
Basically, I just want to have the action as if someone pressed the Manual button on the faceplate after the Interlock clears. It's not really a big deal, because currently all one has to do is press Manual if they want to operate the controller again, but it's just an operability thing that I would like to clean up.

 

[Mispeld]

I've not used the 'Oper' channels into the PIDE, nor the ME faceplate.

I suggest reading up on the '.OperProgReq' and 'OperOperReq' along with '.ProgOperReq' and '.ProgProgReq' inputs. As implied by the naming, this may seem a bit confusing. Also, they automatically reset to false at every execution.

You may try .ProgProgReq TRUE, .ProgOperReq FALSE when setting .ProgManualReq TRUE and CVProg to zero after the interlock clears. I think there is a table somewhere in Rockwell documentation that covers these control options. I could not find it in the Logix Designer online help.