I am trying to understand a grounding system for substations, fault current is something I am not getting. For example, for a small substation with some transformers, if there is a fault in the system how will the fault current flow into the grounding system? If the system has let's say 50 kA full fault current will all of the current (50 kA) flow into the ground or only certain percentage of the faulty current will flow into the ground?
How does this work? an explanation or link to explanation will be very helpful.