In combination with three-phase RMS voltages and currents as the only input parameters, a fault detection accuracy of 99.8% is reached. Insights in the modelling approach as well as training and simulation results are presented. The approach enables further innovation due to reliably detecting faults that remain invisible to conventional relays and fuses, in applications such as power system protection, transmission and distribution networks, and fire prevention. This paper showcases its capabilities on a simulated 220 kV transmission line with a high impedance fault at 10 km, detecting single-phase, two-phase, and three-phase faults at different resistance levels.