Can you do a system.opc.readvalue in Expression Editor

Hi! Is it possible to use system.opc.readvalue in an expression tag? How can I configure my opc connection to make it read from specific OPC server im using, thanks!

You can, via runScript, but it's generally not advised.

Create an OPC tag and reference that in your expression instead...

I've been contemplating an efficient opcItems() companion to my tags() expression function. I've haven't solidified the details, but it's on my to-do list.

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runScript("system.opc.readValue(server, path)",1000) but that inside a expresion tag just don't have any sense. Just create an opc tag where the opc server path is the new opc connection and change this on the tag to the name you set:

and check this OPC UA Client Connection Settings | Ignition User Manual (inductiveautomation.com)