Hi All

I have a small automation network and I am trying to log data from two PLCs via OPC. I have detailed my setup below.

Automation Task

Read data from two PLCs and log to csv file. This will later be upgraded to an SQL server.

Software

• TIA Portal V13 SP1
• WinCC Advanced V13 SP1
• SIMATIC NET V13 SP1
• OPC data logger http://www.opclogger.com/ (currently in trial mode which restricts logging period to 30mins)

PLCs

• S7-1214 DCDCDC - 6ES7 214-1AG31-0XB0 (firmware 3.0)
• S7-1214 DCDCDC - 6ES7 214-1AG40-0XB0 (firmware 4.1)

PC stations

• PG - Windows 7 Ultimate VM
• OPC server – Windows 7 Pro
• HMI – WinCC RT Advanced V13 SP1 – Windows 7 Home
• HMI – WinCC RT Advanced V13 SP1 – Windows 10 Home

PLC Software configuration.

Both PLC’s have a mixture of “Optimised” data blocks and S7300 (non-optimised) types.

OPC protocols

On the OPC server, I have enabled all OPC protocols/services.

Observations

The PLCs have different firmware revisions. When creating an S7 connection to the OPC server in Step7, the older PLC creates two connections (send and receive?). The newer PLC creates only 1 connection (see attached screenshot). I am unable to change the parameters of the newer connection.

Using OPC scout on the OPC Server, I can successfully browse tags and read/write to both PLCs.

Data from the older PLC is only accessible via OPCSimaticNET.S7. Even though the CPU contains some optimised blocks, these do not even show in the OPCSimaticNET.S7OPT tree.

For the newer PLC, I can only read/write via OPCSimaticNET.S7OPT (optimised). This shows me all tags/blocks including non-optimised blocks for this PLC. The folders appear in OPCSimaticNET.S7 but the tags are not shown.

The problem

In OPC data logger, I can only browse and log data from the older PLC. This means I can only log data from non-optimised blocks. This is no problem. I can easily create a non-optimised transfer DB in each plc and send this to the OPC server. This works for the older PLC but since the data from the newer PLC is not available in the non-optimised connection, I cannot send it to the data logger.

The question

Can I force the newer CPU to communicate with SIMATIC NET OPC via the same (non-optimised?) protocol/method as the older CPU? I will shortly be adding a third PLC which is of the newer type, so I need to get this sorted ASAP.

Let me know if you need any more info. I've been looking at this for a few days and I'm stuck. I have tried another OPC data logger from a different vendor with no luck.

Thanks!

I've been working on this issue this afternoon. Sadly, I resorted to installing a demo version of Kepware. I added a non-optimised 'OPC Transfer' data block on each PLC and within 5 minutes I was logging data via OPC data logger. Sigh.

I really would prefer to use Simatic Net for this job. Any suggestions anyone?

Thanks

Hello j.w.eichler

In the newer Firmware Versions of a S71200 PLC you can set the following Settings:

-> PLC->Properties->Protection-> Connection mechanismus-> permit access with PUT/GET communication from remote Partner (PLC, HMI, OPC...)

Set this option to TRUE!!

Perhaps this solves your problem.

In the older firmware Versions the S71200 do not have this protections setting.

Bye Murof

Hi

Both - many thanks for your help.

Yes, I had already found this checkbox and it is ticked already. I still can only access the newer PLC via S7 optimised.

In OPC scout there is only an OPC UA server showing in the explorer tree. Should there also be an OPC DA server? In "Communication Settings" on the OPC server there doesn't seem to be an option for OPC DA.

Thanks

John

Hello

Which OPC Server Software do you use at the moment?

SIMATIC NET OPC Server?Other OPC Server ?

Bye Murof

Hi.

I am using SIMATIC NET OPC server V13 SP1. If I switch the OPC server to KepServerEX v5.20 everything works fine.

Thanks

Today I had similar Problem, first time I use OPC Simatic Net V12. After configure S7 connections, and send hardware configuration to PC. PLC 1200 not apear at opc branch under Simatic.NET/S7..

At PLC I an see :

Conexiones S7: 8; Config: 0

Free Conexions: 6; Config 3

I configure Proyect wiht OPC Server version V8.2 instead V12. Create S7 connections and send new configuration to PC.

At PLC now I see :

Conexiones S7: 8; Config: 1

Free Conexions: 6; Config 0

Now It works OK. But It Seems like With V12 version S7 conections not work fine or There is something to Check.

rlopezmarcos,

Thank you very much for the help!  I changed my OPC version to v8.2 (which does not support S7 optimized connections). This forces both CPUs to use a non-optimized connection. I have setup an OPC transfer DB in each PLC and configured the OPC server with access.

I can now browse all of the required tags on the OPC server and I can now log data using OPCdatalogger from both PLCs.

I haven't tried using v12 of the OPC server but I wonder why v13 has caused such a problem. Perhaps Siemens need to add an option to disable S7 optimized connections in v13.

Thanks again!

I think the confusion comes from the fact that when you need to access optimized DB in 1200/1500 cpus, you have to use Unified Architecture OPC (OPC UA).
Optimized DB do not support using OPC DA.

Another thing is that to access optimized DB, you need to have the plc and PC station (OPC Server) configured in the same TIA project.

In the settings in the properties of the OPC server (in the project), remember to go to "S7 -> OPC tags" and select "All" (or Configured).
After you download this to the OPC Server station, you will find the optimized and non-optimized variables in the "Objects -> SYM:" folder under the "station-name -> cpu-name" of the OPC UA server.

If your OPC client does not support OPC UA, then you have to insert the OPC Server 8.x object.
Then you will find the non-optimized objects in the "Objects -> SYM:" folder in the OPC DA server.