Currently I am using Applicom hardware and their software to communicate to the PLC. I want to achieve redundancy, the way Applicom tells does not suit me. Therefore I want to achieve it by replacing the hardware and use the software. And that software must conform to some standards.

I have to use Applicom's software, Applicom provides Direct-Link PC network interfaces driver, which enables our PLC to communicate on Modbus protocol over ethernet. With this comes an OPC client. My requirement is to have an OPC server which reads data from the PLC and provides to OPC client.

I have not been able to understand the OPC client application code (coded in VC++). Also I have not found any documents related to it.

What I have been able to do is to use Applicom's DLL to talk to PLC BUT that is what I don't want because I don't see any OPC server being engaged.

Is there anyone who can help me in this regard? Any help even to tell me the correct direction would be highly appreciated.

Thanks in advance.

 

did you try set the security levels in DCOM for the OPC.. sometimes the opc cannot connect for that reason.. i had similar problem with applicom in past