OPC connection active but LabView does not see variable changes

Question

I have OPC server on CodeSys. I am trying to read variables using LabView.

I have tried two options:

using DataBinding to OPC Variables in controls
using DataSocket Open, Read, Write, Close VI

LabView returns no error. When I use data binding control it is green and the message is "Active: Connected to OPC server".

Unfortunately when I force variables in CodeSys i see no changes in LabView.

Hello, which API do you use in LabVIEW. Do you use NI DSC or OPC DA client API for LabVIEW? — Khachik Sahakyan, Oct 18 '17 at 07:25
Also, you can use this one, for faster OPC and big amounts of tags: http://sine.ni.com/nips/cds/view/p/lang/en/nid/216309 — Khachik Sahakyan, Oct 24 '17 at 11:42

score 0 · Accepted Answer · answered Oct 20 '17 at 07:32

The problem is solved. Poor diagnostics of LabView Data Socket mechanism was really confusing in this case. The icon shown that variable is "Active: Connected to OPC Server" while it was not.

I have used Server Explorer from http://www.opcconnect.com/freecli.php and then reconfigured everything in CodeSys OPC Server configuration and firewall.

OPC connection active but LabView does not see variable changes

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