Querying Device for Tags to Populate NI OPC Server and OPC UA Server

Updated Sep 16, 2018

Reported In

Software

  • OPC Servers
  • LabVIEW OPC UA Toolkit

Issue Details

I seem to be able to query and populate device-specific (PLC) tags into my NI OPC Server during setup and configuration of the NI OPC Server.  However, I don't seem to be able to do the same with NI OPC UA Toolkit.  Is there a way to populate tags automatically into my OPC UA Server in LabVIEW as I can do with NI OPC Server?

Solution

NI OPC Server is able to populate tags that a device or PLC is reading from and writing to because the NI OPC Server calls into device-specific drivers to communicate with each device.  These device drivers do not necessarily communicate using OPC.  NI OPC UA Toolkit on the other hand does not communicate with devices using device-specific drivers.  Instead, NI OPC UA Toolkit uses OPC UA to communicate with each device. 

It is not part of the OPC design for an OPC UA/DA server to be able to query devices and automatically populate tags that a device reads from and writes to.  As such, NI OPC UA Toolkit is not able to do so either, and NI OPC Server is only able to have such features because it is communicating using device-specific drivers.