PanelView Plus won't change screens

I have an situation where I am attempting to integrate a new machine into the existing machine's PLC and HMI. I still have a day or two to get everything right, but I have run into a problem.

The original system has been working fine with no issues for the better part of a year now so I have a good starting point. For my modification I am adding one (1) analog input module and one (1) analog output module, several screens (pre-developed screens from the new machine’s manufacturer) along with a couple of GoToScreen buttons to get the operator back to a main screen and then, finally, a fair amount of logic to the existing processor (once again pre-developed from the new machine’s manufacturer).

My problem is that after about 10 minutes or so of operation with the new configuration, the HMI (PanelView Plus) refuses to change screens. Initially, it seems to work just fine and I am able to navigate to any screen I like. Once it “locks up”, though, it will still accept and displays login information and numeric values, but it just won't switch screens. When this happens, there are no processor alarms – major or minor – and no indications that any I/O modules are having problems. Via my laptop (connected by way of Ethernet), I am able to see and communicate with everything, no problem. I need to figure out and correct whatever is causing this.

Here is my original system – the one that has been working for many months:

AB GuardLogix 1768-L43S Processor with seven (7) local 1769 I/O modules and an expansion bank with three (3) 1769 I/O modules. The expansion base is connected to the local base via a 1769-CRL1 Bus Expansion Cable. The layout is – from left to right:

Local Base
1768-PB3 Power Supply
1768-L43S Processor
AMCI Resolver Module (1642)
1769-IR6 - 6 point RTD
1769-IQ16 - 16 point 24VDC Digital Input
1769-IQ16 - 16 point 24VDC Digital Input
1769-IQ16 - 16 point 24VDC Digital Input
1769-IQ16 - 16 point 24VDC Digital Input
1769-IF4 - 4 point Analog Input

Expansion Base
1769-OW16 – 16 Point 24VDC Digital Output
1769-OW16 – 16 Point 24VDC Digital Output
1769-OW16 – 16 Point 24VDC Digital Output
1769-PB2 Power Supply
1769-ECR – End Cap

My HMI is a PanelView Plus 1200 Touch – 2711P-T12C4D2.

Now, there are other existing remote I/O connected to the overall system but nothing has changed with respect to them. They are all Ethernet based and connected through an N-Tron 716TX managed switch.

For my modification, I added the analog modules to the expansion base like this:

Expansion Base - modified
1769-OW16 – 16 Point 24VDC Digital Output
1769-OW16 – 16 Point 24VDC Digital Output
1769-OW16 – 16 Point 24VDC Digital Output
1769-IF4 - 4 point Analog Input
1769-OF4 - 4 point Analog Output
1769-PB2 Power Supply
1769-ECR – End Cap

Because the pre-developed HMI screens were all designed to work for another stand-alone PLC (one that did not come with my system), the direct tags in their HMI screens all referenced their own device shortcut name in RSLinx Enterprise. To take this into account, I created the same shortcut name in my HMI and pointed it to the same processor as my existing shortcut for the original machine.

At this point I looking for ideas of what could be causing this and how to correct it. Right now, there are only two things I can think of that might be causing this; first - the 1769-PB2 power supply might be under-powered for my additional modules (although I would expect some sort of processor error if that were the case) and, second - in the PanelView, having two shortcuts that are directed to the same PLC processor might be causing a conflict. To address this second possibility, last night I brought my laptop home and replaced all of these tags with the “new” shortcut name with the original machine’s shortcut name. Tomorrow I will download this version into the HMI and see if that helps.

Anybody have any other ideas? Is there any other information you need?

Steve

Steve,

Just a suggestion. In your factorytalk program, open Global Connections which is in the system folder and then open the tab which says Display.

Are there any tags in the Replace Screen Number column?

Mark

Mark - I think you just pointed me to my problem!

Yes, there is a tag in there, and when I dig into the PLC program I find that there is an instance where a screen number is being called where no screen with that number exists. I now remember that a screen is needed to dispay "XXX UNIT NOT OPERATING". The intention is that this must be corrected prior to the machine being allowed to continue operation.

I am sure that screen-call is being made, but the lack of the screen's existence is causing my lock-up.

I really appreciate this suggestion.

Steve

Steve,

Just to go a little further if there is a screen that needs to be displayed and you know which screen it is, if you open the screen, right click and choose display properties you can assign the screen number there.

Hope this makes sense, i have had a couple of glasses of wine

Mark

Mark - yeah that makes sense. One of the other things along with all the other things I mentioned was to verify that all the screens had unique screen numbers.

I am pretty comfortable that my problem started because my original project file - a backup sent to my by the machine builder - was not 100% the most up-to-date. Consequently, the screen being called did not exist in my project. I have now added this screen to the project and verified it has the correct screen number. I'm willing to bet that this was the sole source of my problem. We'll see tomorrow when I test my new project.

Thanks.

Steve

Steve,

Lets hope that's what it is.

If not let us know and we can try something else.

Glad to help.

Mark

Yep. That was it! I went in this morning, loaded up my modified PV project and a revised PLC program, after a couple of tweaks everything was as it should be.

Thanks again Mark.

Steve