Is there a project loaded into the PLC?  If there is no project, it should be in stop mode.

What firmware is in the PLC and what firmware is in the project you are trying to connect to the PLC with?  They need to match.

Search these forums for "Online Access S7-1200" and you will find lots of help on how to get online with the plc to see the part # and firmware revision, and then you can compare with what is in the project.

phuturephase

Hi everyone, I have a problem with an S7 1217. The PLC goes to stop when I turn it on, I tried with tia portal v15.1 to do the factory reset, firmware update and all the solutions found on the siemens forum. I change the ip address without problems if I ping the plc responds but every time I try to do anything else I get the error:

- unable to establish connection

- incompatible device

Is there a memory card in the S7-1200?  If there is, take it out (while it is powered off).

Is this s7-1200 running anything, or is it a spare PLC you used some time ago for learning? 

phuturephase

There is no project i think. I use it 1 or ore years ago.

The firmware on the cpu is the version 4.0

After power cycling the PLC, go to the "online access" in the project tree for TIA Portal, find the network adapter you are using to connect to the PLC, expand the selection and update / refresh until you see the plc.

Go through the various options in the working pane for the PLC like setting time, factory reset, set name and profinet address, and so on.

Grab a screenshot of the PLC diagnostics buffer entries and the online access showing the PLC and whatever it has loaded visible as well.  Post that here.

phuturephase

 Anyone have a solution?