Is is possible to use the Profibus-DP protocol directly from LabVIEW via OPC?

[vemund]

Hello.

I have a customer who wants to use the Profibus-DP protocol to control a Vacon frequency converter from LabVIEW.

After some research the solution seems to be using a Comsoft LabVIEW Profibus VISA driver. This, however, requires a Comsoft Ethernet Board.
Does this mean that a normal ethernet board cannot use the Profibus protocol? I.e. that a specialized board is required?

In other words, is it possible to use LabVIEW to use the Profibus protocol via an OPC-server?

Also, the Profibus protocol seems to be ment for rather advanced instrument control. Would it be overkill to use it for a simple one frequency converter setup?
(there might be a larger setup in the future, but for the moment we are still in the research phase)

Regards,
Vemund H. Aarstrand.

[becktho]

Hi

If you have an OPC-Server running, you should be able to access it using datasocket vi's.

If you search the LV help or the forums, you should find some examples.

[chrisger]

hi there

"After some research the solution seems to be using a Comsoft LabVIEW Profibus VISA driver. This, however, requires a Comsoft Ethernet Board.
Does this mean that a normal ethernet board cannot use the Profibus protocol? I.e. that a specialized board is required?"

Yes, you need a specialized interface board for your profibus DP network (just as you need one for a CAN network, or a DeviceNet network and so on). There are lots of such boards for Profibus DP, with lots of different interfaces to applications. one of them is an OPC server. One advantage of an OPC server is the fact that the application (OPC client) and the OPC server don't have to run at the same computer.

"In other words, is it possible to use LabVIEW to use the Profibus protocol via an OPC-server?"

Yes. LabVIEW has a built-in OPC-Client. Usage of OPC is in fact standard technique and should work without any problems.

"Also, the Profibus protocol seems to be ment for rather advanced instrument control. Would it be overkill to use it for a simple one frequency converter setup?
(there might be a larger setup in the future, but for the moment we are still in the research phase)"

Profibus DP is rather simple. In "low level" mode you write or read bytes at a specified register address from a specified network member. thats all..

[vemund]

Chris,
Thank you for an informative reply.

As I understand you, this means I will still need a specialized card for OPC-server to communicate with the device via an ethernet cable?

Vemund

[chrisger]

"As I understand you, this means I will still need a specialized card for OPC-server to communicate with the device via an ethernet cable?"

yes, sure. you have to buy a Profibus DP interface card. this card will be delivered with a system driver and a OPC server (if applicable) specialized for that interface card.

The comsoft homepage says  "The package including hardware and software is based on the COMSOFT DF PROFI II board, available in PCI ... . These different formats as well as the real-time VISA driver concept can be integrated in different LabVIEW systems and platform combinations."

This means you have to buy that card which is delivered with a LabVIEW compatible driver (the VISA driver). This driver is one of the many possible solutions to acces hardware with LabVIEW (alternative solution to OPC), so you don't have to buy that OPC server (although OPC is cooler than VISA).

[vemund]

Ok. Got it for now.

Thanx!

Vemund