OPC UA struct data type?

You can take advantage of reading whole structs in OPC UA servers as of Ignition 7.9.12 and 8.0.0.

When you bring the tag in you’ll notice Ignition presents a JSON value. The strategy here is a little involved but it works.

For each of the UDTs you’ll be subscribing to in the PLC you make a corresponding UDT in Ignition. It should have a “Source” OPC tag member that will correspond to the Node with the struct value in the server and as a result have a JSON value in Ignition. Then for each member of the UDT you have a Derived Tag member that references the “Source” tag using the jsonGet and jsonSet expression functions to get/set the member value out of the JSON value.

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