Bug in PID View?

[Kristjan]

I noticed the following today in DMD 2.11.1:

When opening PID View for a certain PID Loop, the viewer actually displays another loop and its parameters (see attachment). I am unable to view two of my loops. Is this a known bug?

[franji1]

Interesting.  I could not duplicate it in 2.11.2.

Can you email your project file to support at hosteng.com?  Not sure what it could be doing.

Try opening up the PID Overview view (View->PID Overview).  Do you see all of your PID Loops in that view?
(you may have to scroll or resize the docked Overview view or undock the PID Overview view to see them all).

If so, try to "double click" on each one in the PID Overview view and see if it opens up the correct corresponding PID View opens.

[Kristjan]

Thank you, I see all loops in the PID Overview and I am able to double click to access their settings. But some headings are still incorrect.

I just sent the project to support.

[franji1]

I just sent the project to support.

Got it.  Definitely seeing strangeness.  Will need to look a little deeper.

Are you using the latest firmware for BRX (2.11.3)? Also, recommend updating to latest Designer software (2.11.2).  I don't think that will address this issue, but those are better than previous 2.11.x versions.

[franji1]

It's a bug.  It's been there a LONG time.  It was an easy fix.

Until we come out with a new version with the fix, the best workaround is to NOT use the Combo Box drop down in the Form section of the PID view.  When you want to open up a new/different PID View:

• use the PID Overview view (View->PID Overview) and double click on the one you want
• use the PID View Online Toolbar and that will prompt you (via a different dropdown combo box) for the PID loop you want

So sorry for this.  Thank you for finding it - I can't believe this hasn't shown up sooner   

[Kristjan]

Thanks again, nice to know that you identified a bug 

Your proposed workarounds are not really solid either. Both options you mention are opening the PID View with diverging loop names, see attachment. But at least now I know there will be a bugfix in an upcoming release.

Out of curiosity, is this a bug in DMD or in the PLC? I.e. is the PID View being populated with data from the project file on disk or data directly from the PLC? Can I fix this by deleting the PID structures and create new ones?

[franji1]

Definitely a Designer bug.  The mapping of the drop-down in the PID form view back to a specific PID was not correct.

So sometimes, when you pick a different PID loop in that drop down, it thinks it's the same one that's already there.  The drop down shows what you selected, but the view believes it's still on the original.  Or even worse, a THIRD PID loop will be shown in the view.

The name in the TITLE BAR tab is the ACTUAL one being utilized by the view.  The one selected in the drop-down is not (unless it happens to match the one in the title bar).