We introduce a series of models which describe the ‎propagation of a disturbance created during a short in the electric network. The phenomena is technologically interesting since using the time of arrival of the disturbance at two sensors one can calculate the exact location of the fault. We start from a very simple circuit models that describe the effects of the short which can be solved analytically under simplifying assumptions or numerically. Next we introduce distributed models both dispersion-less and dispersive which describe the propagation of the signal along the electric network; we conclude that for high frequencies the dispersion is minor and does not affect the accuracy of the fault location.