Having Tag Issues

Hello Everyone,

I am running into Tag issues and hoping if anyone can help out. I am working on a small school project, trying to get familiar with Ignition. I created a simple Push Button Program which powers on an LED. I am using the Allen Bradley MicroLogix 1400 Controller, as you can see there is my Ladder Logic code on the RSLogix 500 Software and I am simply trying to use a 2 Toggle Push Button to turn on the LED. When I push the button on Ignition the Button turns True "1" momentarily then switches back to "0". As well a pop up error occurs as you can see from the image. If anyone can help me out with this issue and provide tips/suggestions, I would greatly appreciate it.

How did you type in the OPC Item Path? Normally the path has some extra rubbish on the front. An example might be ns=1;s=[Testing]B3:0/6

I would press the little PLC symbol next to it and find your tag. This will then add all of that information for you.

If that doesn't work, check that your provider isn't in read only mode

Hi There! How would I find the OPC Item Path? Or where is this OPC Item Path Located?

If you click the small PLC/Device symbol next to your OPC Item Path on the Tag editor, this will open a window of your connected devices.

Navigate through that to find this tag you want

Giving it a try

To check the provider isn't in read only mode where can I locate that?

Should be in the device connections and in the OPC connection

I'm no micrologix (or PLC in general) guru, but I wouldn't have thought you could write to inputs.. Inputs are for physical inputs like push buttons, switches, etc. Try creating your scada tag in the B register

That error msg isn't due to the tag provider being in read only I don't believe, it's that the node (your opcitempath) itself in the OPC UA server is read only, and that is probably coming from the plc as per above.

Also yes, that opc item path looks wrong in your tag config. How did you create that address? I can't recall if you can browse tags in a micro, but what happens if you click the plc button to the right of the opc item path field and expand down to your device in the tree?

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You can't, use internal addresses like B3,N7, etc.

It works! Thank you very much. The solution was within my code within RSLogix 500, the Input had to be moved to the B register. Output was fine where it was, and as well making sure I choose the correct OPC Tag Path.