Allen Bradley PLC Channel Communication Problem with ServerExplorer and LabVIEW

[NelsonO]

I am currently communicating with AB SLC5/05 PLC via ethernet. I do have RSLinx OEM OPC Server and NI's IA OPC Server. I am able to write to all channels on my output modules except for O:4/0 and O:5/0. I do have an output module in slot 6 and I can access O:6/0. How can I access O:4/0 and O:5/0?

[steven@ni]

Nelson,

The IA OPC Server CD does not contain software that supports the AB SLC5/05 PLC. However, you should be able to access data directly from the RSLinx OEM OPC Server.

To verify functionality of the RSLinx OEM OPC Server, you can download a generic OPC client called Server Explorer.

For more information about addressing allen bradley plc's, please see the document titled "Notes on Allen Bradley PLC Addressing"

These documents should give you some troubleshooting tools. Please note, that if yo
ur OPC Server is not browsable, then the usefulness of the server explorer may be more limited.

After reading all of this, you should be able to simply read data directly from the plc registers by using datasocket and the correct url.

[NelsonO]

IA OPC Server CD did contain Server Explorer. Using both Server Explorer and LabVIEW I was able to read or write data to almost all PLC registers. I could not write to O:4/0 or O:5/0. I could write to O:4/1 thru O:4/11 (only 12 channels in O:4)and O:5/1 thru O:5/15, all of O:6 including O:6/0. My problem is limited to only two bits or channels - O:4/0 and O:5/0.