Tag does not exist accessing RSLinx 2.55 using Plant Connectivity 2.1.6.1

[Former Member]

When accessing an RSLinx 2.55 OPC server using Plant Connectivity 2.1.6.1 we consistently see the following in the error logs of the PCo agent:

HResult 0xc0040007

A quick bit of searching identifies this as a standard message from an OPC server indicating that the requested item ID is unknown. Using a series of alternative OPC test clients from various vendors (Matrikon, Kepware, etc...) I can verify that the item ID in question does exist and is readable (attempting to address any security configuration questions). Additionally, we have been able to use simulation servers from the vendors above and the one available within MII to verify that PCo is not having issues browsing tags as advertised by other vendors.

I've reviewed a number of additional threads and there appears to be a series of them that relate to issues between RSLinx and other offerings (UDS) in this space. I have verified the items discussed though I haven't seen anything specifically involving PCo.

Does anyone have experience with RSLinx and PCo that they would be willing to share? Unfortunately, we don't have much leeway regarding its usage at the facility in question.

[former_member192939]

As David mentioned, I have used manual entry with a different OPC server, it is running without any issues for almost 2 years now ..

Regards,

Ajay.

[former_member196557]

David,

There appears to be an issue with PCo browsing RSLinx OPC Servers. We had a similar issue and our workaround was to Manually add the subscription items to the Agent Instance by clicking on the Manual Entry button on the Subscription Items tab for the Agent Instance:

Name is the PCo tag name you want to identify

Source is the actual RSLinx OPC Tag Name (i.e. [TOPICNAME]Address, ex: [MyTopic]N7:0)

Deadband if required, otherwise leave as is.

While you cannot browse, you should still be able to see the data in your Agent Instance Notification.

- Steve

[Former Member]

Thank you, Steve. That took care of the problem straight away for the subscription items. For future reference, if you also what to use the query capabilities MII to read or write (store) data back to RSLinx through a PCo query in MII make sure that you configure the source system with aliases for the tags your are interested in and change the tag query tab on your agent to read from the alias you set up. Communication is working flawlessly at this stage, despite the noted inability to browse.