The distribution of smart grid applications to different physical devices not interconnected with physical sensors has opened the possibility for software virtualization allowing flexible localization of functionalities. Harnessing wireless 5G technology enables edge computing and locating smart grid applications at the edge. In this paper, we study edge computing supporting medium voltage grid fault location, discuss the challenges and benefits of bringing smart grid applications to the edge, and demonstrate fault location operation on an edge device. The challenges and benefits undertaken for a good business case are highlighted. The demonstration shows that the total data rate in urban areas is the critical parameter, whereas latency due to large distances and the general availability of edge resources are the most significant issues in rural areas.