Ethernet - Profibus bridge

  • Thread starter Michael Griffin
  • Start date

Thread Starter

Michael Griffin

I believe that some time ago I addressed this list about Ethernet - Profibus bridges, however times change, and I would like to see if anything
new is available.
I am working on a project where I will need to connect a series of PLCs which are already equipped with Siemens L2 (Profibus) ports (mainly S5-95U). I wish to connect them to a TCP/IP Ethernet network so that this Profibus network can communicate with a server which will collect production statistics. The application software requires an OPC connection.
The Ethernet network is a high speed system which already carries various general network traffic (it is not a dedicated control network). No control is contemplated, only monitoring. The reason for using the Ethernet
network is to allow flexibility in relocating lines within the plant.
To implement this, I believe that I need a Profibus to Ethernet bridge. However, I have not been able to find one. I don't want to develop
anything, I would like to buy a working one off the shelf. Each line would have its own bridge (or more than one for large lines). The bridge should be as small as possible (of course) so that it can normally be mounted inside an existing panel. I am currently at the stage in this project where I would like to finalise the bridge selection.

The criteria are:
- Profibus to Ethernet.
- off the shelf.
- small and reliable (and 24VDC powered if possible).
- easy to set up and configure.
- both Profibus L2 FDL and Profibus DP (with the PLCs as slaves) - this could require either two bridge versions, or a configurable bridge.
- has an OPC server (driver) available.
- reasonably priced.

1) Is anyone aware of such a bridge as an actual existing product?
2) Is it true that the reason that such a bridge may not be available is because the Profibus committee is still arguing about how to do Profibus over Ethernet?
3) If so, does anyone know when a standard will be approved? When will products based on this standard be available? Is the situation hopeless?

I have looked on the Profibus web site without much success. I have found a product from SST (XLink) which will allow me to make the connection, provided I treat the Ethernet side as if it were a Modicon, GE, or AB system (the XLink will make the translation). However, this seems likely to be confusing to administer, so I would like a more direct system if possible.
I have looked at the following:
- The Hilscher PKV 40 does not seem to be a finished product (at least for the Profibus version).
- Siemens does not have a bridge.
- The ICT Profigate does not use OPC (which my application software requires).
- I cannot seem to get any information on the VCOM Profigate. I'm not sure if this product actually exists.

Michael Griffin
London, Ont. Canada
[email protected]
Michael and list,

Here is from Dick Caro's last post to the Industrial Ethernet List:

"Profibus International will have a news announcement on August 12 concerning their preferred Ethernet and IP position."

I don't know of any bridges available off-the-shelf. Have you tried contacting either the PTO (US) or PNO (Germany) directly via e-mail?
If anyone knows of this, it seems they would. The sites are not always up-to-date.


Willy Smith
Numatico SA
Costa Rica

Gerard Leemkuil

At this moment we are using Siemens and Allen Bradley PLC connects to a Windows NT 4.5 systems. For Siemens S5(95UDP2) and S7 (315DP2) we are using profibus cp5613 card with a OPC driver. For Allenbradley we are using a data Highway KTX card and a OPC driver. Both groups or PLC's are working
together with RSVIEW SCADA systems. These systems are running for a year without any problems. For other PC's stations Rockwell has software tools for interconnetion.

You may also use Borland Delphi or Builder for the OPC to SQL connection and for a SQL Server you may use Cache from Instersystem as central database running on a Linix PC.

Minimize the number of Jobs on the Windows NT stations you will get a quicker responce. Check alway the drivers for the PLC Network cards. For this moment are the drivers from both PLC manufactors error free.

Regard Gerard Leemkuil

Adrian Chesney

With regards to your Profibus-Ethernet bridge, I found in The Industrial Ethernet Book at a product by Softing called PROFIgate which claims to "enable users to access PROFIBUS networks via Ethernet TCP/IP." There are one or two other products within the directory that might be suitable.
Adrian Chesney

Marcos Giorgianni


There is a company in Brasil that could help you. Try:

They have a product called RTDS - Real Time Data Server, maybe you can get your bridge in a very easy way.

Other suggestion is a German company called Beckhoff (


Michael Griffin

I looked at this product already, except I had mistakenly listed it in my message as "ICT", whereas ICT is actually simply a dealer for Softing. The problem with this product for my application is that it doesn't offer an OPC interface, while the application software I am considering requires one. The Softing Profigate requires you to include their own drivers in your
application, and this is not an option I have.

Michael Griffin
London, Ont. Canada
[email protected]

Rob Hulsebos

>Here is from Dick Caro's last post to the Industrial Ethernet List:
>"Profibus International will have a news announcement on August
>12 concerning their preferred Ethernet and IP position."

Well the information was released today (10/8) and can be found on the website. But be warned, there isn't much news there... I asked the PTO for more details and will let you
know what I learn about this "ProfiNet".

Then, about bridges.., I think you will most likely only find gateways.

I'm anxious to learn how the strict timing-requirements of DP can be met, and how multicast- and broadcasts are implemented over Ethernet via bridges to RS485 devices. I have read earlier that only the non-cyclic DP functions will be made available on Ethernet, but I have also read documents that stated that the cyclic I/O functions will be provided on Ethernet too.

In the Profibus telegrams, there is a field reserved for subnet-addresses, but to my knoweldge it isn't use anywhere. This would give you the possibility to build networks with more than 126 devices. The only solution now is to connect gateways.

Rob Hulsebos

Michael Griffin

I have seen several companies who have what looks like ideal hardware for my application, but they don't have Profibus support (yet). I think what has been happening is that everyone is waiting for the Profibus committee to come out with a standard, and that this process is taking a lot longer than any of them expected (which may be why some companies have bridge hardware but no drivers). The phrase "their preferred Ethernet and IP position" doesn't give me a lot of confidence about anything being finished in time for my immediate project. It sounds like they are still arguing about general strategy, not putting the finishing touches on
things. I suppose I will see what they have to say in a couple of days.

Ideally, I am looking for something which is as transparent as possible to either end. The OPC server would probably have to know about
this bridge because the actual Profibus node addresses could be duplicated on different Profubus networks. This means the OPC server would need to know that a particular PLC address consists of an Ethernet address (the address
of the gateway) plus a Profibus address (the address of the PLC). The separate Profibus networks don't need to communicate with each other, they just need to respond to data requests from the PC server.
Which data is requested and where it comes from would be administered by the OPC server, not by the bridge. The simple data
concentrator, or the protocol converter which maps to a network as if it were a single PLC (e.g. maps multiple sources as a single address space) is not what I am really looking for since it adds another device to update whenever a change is made.

In the end, the Profibus commitee's plans for Ethernet may not correspond to what I need for my application. Thank you for your information

Several other list members have suggested other hardware. However, their suggestions involve how to connect Profibus directly to the computer which runs the application. I am looking for a bridge which allows me to connect Profibus to Ethernet, so that I can locate the actual computer somewhere else. To explain this further, the PLCs are connected via Profibus to a bridge, which in turn is connected by Ethernet to the actual computer (located somewhere else in the building). Each production line (which has a
number of PLCs) has at least one bridge. Each bridge is connected to 6 to 12 (or possibly more) PLCs.

Michael Griffin
London, Ont. Canada
[email protected]

Michael Griffin

As a correction to one of my previous messages, it turns out that Softing's Profigate does indeed work with their OPC server. I haven't seen this information anywhere on their web site or in their data sheets, but I was contacted off list by Softing who told me that it does indeed work with their OPC server (although in DP mode only). Apparently, the OPC server talks to their special driver which in turn talks to the hardware in a
manner similar to their normal boards.
I believe that many of their customers don't bother with OPC, but rather talk to the drivers directly. This is not an option I have in my application. Has anyone used the Softing Profigate (with or without OPC), and would they care to make any comments on it?
I still have to determine whether Profibus DP mode is sufficient for my application, or whether I really require FMS. If DP is suitable, then possibly my gateway problem is solved.

Michael Griffin
London, Ont. Canada
[email protected]

frederic KUSCH

(excuse me for my english !!)

The society APPLICOM INTERNATIONAL make a lot of products for de communication beetween several protocol. It has the driver for Linux and Windows,
the PC-CARD or special box.