Hello,
Could someone please help me understand on creating UDTs? I’ve read a few of the posts but still not very clear on how to use UDT in OPC tag path.
Do I need to create a standard OPC tag first before creating a UDT?
Right now I am using indirect tag path to point to the correct processor but then I have to create a copy of the same tag for each cell because of the opc tag path binding.
I would like to use only one tag but change the OPC tag path binding with UDT to reduce tag number to one.
Thank you,
Blue
If you click on the pencil beside the opcitempath and click edit, you can then add bindings to your path to make them dynamic. Use the icon buttons in the right of the binding editor to add parameters and other options
I still don’t get it…
A little bit more help please?
For example, create a parameter on your UDT called PLCName and then set your OPC item path to:
ns=1;s=[{PLCName}]B9[0].0 and then you can pass the plc device to use for the UDT at the instance level. You can do the same thing for the address parts as well. E. G. For logix:
ns=1;s=[{PLCName}]{DeviceName}.Status
May be I am not define my UDT correctly?
And this is my opc tag, with the error
Got it, time to redo…pretty much all of my tags but oh well it will be easier in the long run.
Thank you nminchin !
Yep, your UDT is a template for things, devices, etc and should contain the tags for that thung/device. For example a pump udt might have status, mode, start/stop commands, alarms, etc. And would use the OPC item paths as I mentioned in my 2nd example. Then you make instances of the UDT in the Tags tab and set their parameters to customise the instance to each specific device.
