The increased accuracy into the fault's detection and location make an easier task for maintenance, this being the reason to develop new possibilities to a precise estimation of the fault location. The paper presents the results of the implementation of two fault location algorithms in ATP-EMTP program. Some ATP-MODELS modules were associated to the ATP model of different transmission grids, these modules being developed on basis of Takagi algorithm applied in two-machine systems and on basis of one algorithm processing synchronized positive-sequence phasor quantities on both transmission lines' terminals. DFT and A3 type filters were used to calculate the fundamental frequency phasors of the transient voltages and currents. There are presented some simulations', the considered parameters of the presented analysis being: line's load, fault's type and resistance and fault position along the overseen line.