Faults studies form an important part of power system analysis. The problem consists of determining bus voltages and line currents during various types of faults. If the fault location is known the problem can be easily solved. But if the fault location is unkown, it is difficult to solve the problem. If the fault location is known the problem can be easily solved. But if the fault location is unkown, it is difficult to solve the problem. There were attempts to find the critical distance of a fault that will cause certain pre-defined voltage dip at certain bus, and the problem was easy to be solved in radial systems, but yet non of the existing researches could provide proper solution for finding the crtical distance of the fault at certain line that will cause predefined voltage dip magnitude at certain bus.in meshed power system. The paper provided proper solution based in Gauess Seidal to find the critcal distance in meshed power system
