I am hoping someone can help me, I have current operating system using V7.9 I have created UDT’s and set the “Data Type Parameter” name as “DeviceID”. Within the actual Tag, “DeviceID” is pointed to the tag in the PLC. This works and is a convenient way to create similar tags within the project. I am creating a completely different project with V8.1. If I create a UDT and point the “DeviceID” to the PLC tag, it reads as a bad connection. In V8.1, if I use the “Link” icon in the “OPC Item Path” and physically navigate to the tag within the UDT in the PLC, then it will read as “Good”. I have followed the “Create UDT” course on the University, with no success. Does anyone know if there is a problem creating UDT’s in V8.1?
Version 7.9 SCADA is connected to Allen Bradley CompactLogix V28
Version 8.1 SCADA is connected to Allen Bradley ControlLogix V32
See attached “.pdf” showing pictures and a better explanation.
Thanks for the support.
UDT_Configuration.pdf (1.4 MB)
Might be useful if you show us what you’re doing, for example a screenshot of one of your tag’s config in your UDT definition. Otherwise it’s a bit of a stab in the dark
Edit: OK, I completely missed that PDF (or rather I thought it was the user manual or something…) I blame lack of sl33p
V8+ changed the handling of UDT parameters to be more expression-like as opposed to simple string substitution. An upgrade-in-place, or a restore of a v7.9 backup into v8.1, invokes some conversions to make all simple cases work in the new format. If you just export/import tags, you will have to make the adjustments yourself.
And some complex cases might simply not work with the conversion tool.
Sometimes, I run into this problem even when my parameters are correct:
A few things you can try that seem to seem to get the tags to pick up:
• Arbitrarily change a parameter and then change it back
• Navigate via the web browser to the OPC connection page, open the editor and click save changes without making any edits
• Open the specific device connections via the web browser and click save changes without actually changing anything
What we do need though, is an export of the json of your UDT definition. Screenshots won’t capture important info that’s under the hood
Thank you all for your thoughts and comments.
I’m not currently on site and I don’t have remote access to the gateway. I will give the suggestions a try when I’m on site.
FYI: this was a new project, I didn’t import existing tags from V7.9. I just manually entered the PLC address in the same format as V7.9.
Once again, I am grateful for the advice and support; Thank you all.
A further update to my UDT issue with Version V8.1.17. I have re-installed Ignition, and started from the beginning, i.e. configured the gateway, database, PLC connection, project etc. I have then created my UDT’s and created tags from those UDT’s and all is working as expected. I will happily put my hand up and admit that it was probably a “Me” problem, but after the re-install, it works as I expect (same as V7.9).
Again thanks to all who commented and suggested solutions.