Configuring S7 CPU as slave on DP coupled to SST card in CLX rack

[dmbartender]

Hello all,

As the title says, I essentially want to communicate from CLX L62 CPU to a Siemens 316 CPU using an SST PB coupling card in the CLX rack.

I have configured the SST card to correspond to the CLX.
Then I set the DP of my S7 CPU to be a PB slave (node = 3).

However, I can't even get the SST card to find the S7 processor. I'm thinking that it wasn't correctly set as a slave, even though I downloaded the HW config and system data. I say this because the SST card can find other nodes. Just not the S7 CPU.

Is there something special I have to do to configure the DP port of the siemens cpu, besides choosing as a slave with a specific PB address?

I would appreciate any help.

 

[JesperMP]

Yes, you have to define the I/O address areas that correspond with similarly configured I/O addresses in the Profibus master.
Notice, what are outputs in the S7 slave must be inputs in the master, and vice-versa.
I dont have the time, so go to siemens support and search for "S7 Profibus slave" and there should be a number of FAQs, one of them describing how to set it up as a slave to a 3rd party master via a GSD file.

 

[dmbartender]

I found something on siemens support that described how to set-up a CPU as a DP slave. I couldn't find however anything that they did differently. It may be that the CPU is correctly configured, and that the problem lies with the SST software. It's hard to say, as I have little experience in this area.

I did however set up the I/O areas, however I'm just looking first to get communication in general.

Can someone explain what a GSD file is? I don't need it to just configure my S7 CPU as a DP slave for the SST card, do I?

 

[JesperMP]

Can someone explain what a GSD file is? I don't need it to just configure my S7 CPU as a DP slave for the SST card, do I?

It is the other way around. The master has to have the GSD file in order to know how the slave is to be configured. So you have to import a GSD file for a 316 as a slave into the configuration of the SST master. Look into the documentation for the SST card how to accomplish that.

If everything isnt setup properly, you will not achieve a connection at all. The i/o areas must match.

 

[dmbartender]

Hi Jesper. I downloaded the GSD file for my CPU, and configured the CPU as a slave of the master SST card with this file. Nevertheless, I still can't see the CPU as a node on the profibus...I'm speaking of the online window of the SST Configuration SW, where it just preliminarelly scans the PB network looking for any slaves. I can find others, just not the CPU. There must be something special I have to do in S7 to so that it really registers to the CPU that it's a slave. I'm still pretty new to S7, so I'm not sure what else that could be.

I've downloaded the HW config and system data, but it still doesn't work.

About the IO areas having to match, I agree. But to get started I assigned 1 arbitrary IO area for one of my nodes, and the SST card can still find it, even though it's IO area is not correct. Of course it has an error, but at least it was found. My first goal is to find my CPU as a PB node at all.

 

[pimpim32]

Wiring, end resistors are ok?

How you go online with S7?
If you have the CP5512 you can make a test and see the nodes

 

[JesperMP]

Hi again.

I assume that you have downloaded the HW config to the S7 PLC.
So you should be able to see if the S7 is reachable as a slave on the DP network.
I have a CP5511 that has some diagnostics functions, including that it can display a list of active and passive nodes in the DP network. So I can "see" if it is available at all. Other cards with this functionality are the CP5512, CP5611 and CP5621.

 

[dmbartender]

I don't have a CP5511, but rather a USB to MPI converter. Anyway, with the SST software, you can do a search for profibus nodes on the network that the SST card finds. It can find every node but the processor. I've gone online with the HW config in siemens, to make sure that it's still configured as a slave. It is.

I've tried everything I can think of, but nothing has worked up to this point (I don't have much experience with siemens HW though either). End resistors and Profibus cable connections are also ok.

 

[JesperMP]

OK, that confirms that the S7 is not reachable at all.

I forgot to ask, is it a 316 or a 316-2DP ?
Are you connecting the 316 as a slave via a CP342-5 or the onboard DP port ?
If it is the first, then look up the diagnostics buffer of the CP342-5 (not the diagnostics buffer of the CPU).
If it is the latter, what does the hardware diagnostics say ?

Anyway, I suppose you have checked the obvious such as baudrate and node address.