One tag in UDT has a Bad Quality

I have a UDT that reads data from a UDT in a Logix processor (v30). Every tag in the PLC’s UDT is read by Ignition just fine except for one Boolean. It fails in both the tag browser in the designer and the OPC Quick Client on the gateway’s web page. The UDT is used on multiple processor and tags and ALL are failing. I am at a loss as to why. Everything else is working just fine.

I am calling Support tomorrow but thought I would post here just in case… Thanks.

External access set to none?

I don’t have access to the code but they are all part of an AOI definition. They problem tags were added after the code I have and they may be Set to InOut which may be the problem.

You will need access to the code. If the param is InOut, you can simply point at the real source of that data. If the AOI member has External Access == None, you simply cannot read that member. You should also look at this discussion of AOIs:

1 Like

Just had the customer check the PLC and indeed the tag did not have External access. Will use a different strategy to solve the AOI problem. Thanks all.