IBHLink S7++ / CP 342-5

[alextroto]

I'm trying to develop a software which should read tags from a Simatic S7-314 / CP 345-2. For this I'm using S7.NET + c#.
I'm using a IBHLink S7++ gateway between the profibus and ethernet networks. If I'm using the MPI interface of the CPU, everything runs as expected. But If I'm connecting to the profibus interface from the CP 345-2, I cannot read anything from the PLC DB.
Any ideas what could cause the problem?
Thank you,
Alex

 

[JesperMP]

Can you see the CP when you go to the diagnostics page as shown at the bottom of this wiki page:
https://wiki.ibhsoftec.com/en/IBHNet:IBH_Link_S7

In you application, are you setting the correct rack/slot configuration ?
I believe that the principle is the same for DP as for MPI
https://wiki.ibhsoftec.com/en/IBHNet:RFC1006_Communication_IBH_Link_S7++/S7++HS
So if for example the CP has DP address 5, you must set Rack = 0, Slot = 5.

N.B. going via a Profibus CP in the S7-300 rack actually doesnt give you any advantage.
The data still have to pass via the MPI bus that is in the backplane of the S7-300 rack.
With such an adapter you can just as well use the MPI port in the CPU.

 

[alextroto]

Hi Jesper,
Yes I can see the CP in the diagnostic page. Moreover, I can setup the IBH Link on PG-PC to manage the S7 station. Also, I'm entering the right rack/slot DP address for the CP. If I'm entering a wrong DP address, I cannot connect at at all, I have another kind of error message.
I need to use the profibus/CP 345-2, because the S7 is already in production, unfortunately I cannot change the architecture.

 

[JesperMP]

You dont change the architecture if you put the IBHlink on the MPI port of the CPU.
If the MPI port is already used, then plug the IBHlink first, and then plug the existing MPI cable on the piggy-back port on the IBHlink.

 

[alextroto]

Between the IBHlink and the S7 station is 200 m of profibus cable. As far as I know, MPI it's limited to 50m, correct?

 

[JesperMP]

I see, and ethernet is usually limited to 100 m.

Unfortunately I cannot tell why you cannot read DBs when you are connected to the DP port on the CP.