How to convert labview data into opc tag

[Ramme]

Hi all,

Can any one please tell me how i can convert the labview data global into a OPC tag? I have some data globals reading and writing data to the globals. Now i wanted to use a PLC device to send its outputs to the field.

The PLC device will supports the OPC tags so i wanted t create OPC recognised tags in my labview. Is it possible. I saw that labview also having OPC functinalities. Please any one guide me in doing this.

I will be very thankful to them

Ramme..

[tst]

You will need to have an OPC server installed on your computer and configure the tag and the communication there. Once you have that, you should be able to open the global's front panel, right click on the specific control you want to associate and select Data Operations>>Datasocket Connection and from there browse all the OPC servers installed in your system or your network and their tags.

Find the correct tag in the tree and that should be it - the global should be associated with the tag. Note that working with Datasocket for OPC is not recommended unless you have a fairly small number of tags.

[Ramme]

Thanks for the reply, i have connected to opc tags in that manner as you said. I succeeded also.. Upto reading and writing to that opc tag is ok.,... what my question is how i can make a opc server using my globals of data?

One more thing you said using datsocket for more number of data is not recommended, then what is the alternative.. please suggest

Regards

[tst]

As I said, I believe you can do this for globals as well by opening its front panel (double click the global) and using a DS connection for the control that represents that specific global.

As for other alternatives:

• NI sells the DSC module which comes with an OPC server and with better tags.
• You can use a common protocol like Modbus to interact with the PLC.
• You can use the custom protocol used by the PLC.

The last two would require that you would change your program structure, so you would only want to use them under certain conditions.

I believe the practical limit for OPC tags with DS is a few hundred tags, but I never used it myself so I didn't run into it. You can try searching the forums to find out more.