Hi Murof,

https://support.industry.siemens.com/forum/ae/en/posts/two-single-user-project-and-future-engineering-station/279731

As per in the above post, in the case we have a simatic manager, is it best to import the single station OS into the simatic manager and then perform the changes and do download from simatic manager. 

Could you please also tell  whether by doing this way that the archive data will not be lost.

We also have 1 ES( Step7 5.5SP2 and Wincc RC 7.4) and two single station OWS.( Wincc RT 8.0 ). This is a existing running plant and we are looking to add one more ET200M IO rack and also changing the CPU from S7300 to S7400

Also since there is a change in the version of RC 7.4 and RT 8.0 , we are looking to upgrade with minimum changes to the system. ( Instead of integrated whether doing the changes on the RT with the 2hr free window provided is a simple way to do Wincc engineering on RT station itself because if we want to upgrade RC to 8.0 , then the Windows EWS OS which is now Windows 7 has to be changed to Windows 11 and all the software in the EWS has to be upgraded which may be a tedious task)

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Split from Engineering Station & WinCC Server.

Hi Murof ,

             Thanks for the reply. We do not have redundant server pair or server client. We have two single station OS with Wincc 8.0 RT 

I agree with your point that all ES,Client,Server should have the same version and update.

But currently the running plant is having Wincc v8.0 on OWS 1 and OWS 2 which are single station project and not integrated in the Simatic Manager.

EWS/OWS Wincc  7.4   Step7 5.5 SP2  Windows 7 

OWS-1 & OWS-2 Wincc RT 8.0 Windows 11

In this condition can we maintain the version different on EWS/OWS and OWS-1 ,2 or it is mandatory to upgrade the EWS to Step7 5.7 SP2 and Wincc 8.0 so that the versions are same on EWS/OWS and OWS . I feel we may then need too upgrade all the softwares in EWS/OWS and also the OS to be changed to Windows 10 from Windows 7.  Since this is a running plant we are looking to do this with minimum changes to the existing system.  

Could you please advise is it advisable to upgrade EWS/OWS or manage with the same software and modify the changes individually in each OWS station.

If we do engineering changes on the OWS itself what might be the consequences. 

Hi Murof,

              Thanks for the reply. We are also upgrading the EWS to Step7 5.7/Wincc v8/Windows 10  and i went through the compatability tool to select the proper software version, Windows OS and compatabile PLC,IO  modules