This article seeks a universal method for calculating arc resistance, which would allow one to analytically estimate the arc resistance at a certain point in time. The development and occurrence of a short circuit through an arc is a random, unpredictable value. Traditional methods for calculating arc resistance use values of dead short circuit currents, which leads to a distortion of the result downward. Consequently, when setting resistance elements using such data, there is a risk of not working in the event of a short circuit through an arc. The paper discusses an analytical method for finding the arc resistance, where the calculated value of the current through the arc is found from the system of time-depending equations and compiled on the basis of network parameters depending on the short circuit point. This eliminates the use of dead short circuit currents. The results of the work performed can be used as a theoretical and research basis for improving of the methods for selecting settings for polygonal resistance characteristics of distance protection.