Within ProfiTrace there is a feature called topology scan. The feature can give an overview of your network including cable length.
ProfiTrace (37020, 37021 & 38022)
My topology scan is not showing the correct topology overview and some devices where failed.
What is the reason?
It could be that you have convertors on your network as Repeaters or OLM's. These devices have a galvanic isolation what makes the electrical signal behind the convertor to a different signal.
The topology scan is using the electrical signals what makes it impossible to create a topology.
By disconnecting the convertors, you can create a network overview per segment.
It can also happen that there is already reflection on you PROFIBUS signal what makes it also impossible for the topology scan to create a network overview. This reflection must first be solved before you start the topology scan.
Read the pop-up carefully to create a good overview of your network.