What happens?
When logging in, an online change or a download request appears although the PLC project has not been changed.
When does this behaviour occur?
The above-described behaviour occurs sporadically if you log in with a PLC Designer >= V3.6 to a controller on which a project is running which was created with a PLC Designer < V3.6 and has been downloaded to the controller.
Which products are affected?
PLC Designer V3.6 and higher
Short-term measures/recommendations:
Use the PLC Designer version with which you have downloaded the PLC project to the controller for logging in.
As an alternative, you can also log in to the controller without any change. In this case, the controller program will continue running without any change and possible changes will not be transferred to the controller.
Evaluation:
In the event of servicing or maintenance it is from time to time required to log in to the controller with the PLC Designer to have a look at the variable values in the PLC logic for diagnostics purposes. It may happen that the PLC Designer version used by the service personnel is a later version than the version that was used to load the project to the controller. In this case, an online change or a download request may appear. The execution may lead to an unintended change in the PLC logic. For this reason, it is recommended to log in without any change in this case.
