Hello,

GNit

In my vb.net application, I need to read / write some tags of PLC S7 1200. Communication thru profinet.

Expecting valued response.

Thanking you in anticipation.

 documentation to expected used interface library - Simatic NET. On other side, here is Forum to PLC programming, interfacing problems not 3-rd party higher language as VB .NET is. I recommend also check MS Forum with VB Conference with VB exact support.

To PLC side, in case of your S7-1200 HW firmware version higher than 3.x (4.x and higher) you need probably set access to your PLC as enabled from external sides inside PLC options, Enable access with PUT/GET. If you want use some 3-rd party access interface not Simatic NET library, maybe look for Snap7 or similar libraries. Your PC app acts here as Client and PLC as Server so I expect no changes or programming on PLC side with this access option.

Update: I see that you want communicate over Profinet. Can you better describe this decision? I expect here maybe some missunderstanding, looks like you mean S7 protocol not PN, correct?