1. A method of analyzing a fault condition in a cable carrying AC power, the method comprising: detecting a fault condition in the cable; upon detecting the fault condition in the cable, obtaining data concerning characteristics of the AC power for a predetermined period of time; performing a Fourier transform of the data; and using the Fourier transformed data to determine whether the fault condition comprises a cable fault; wherein the data comprises oscillographic data indicative of a time varying signal; and wherein the time varying signal is generally periodic and the step of performing includes Fourier transforming current data acquired over a time period which corresponds to about one-half cycle of the signal.