On the basis of the computations of electric-field strength between the electrodes, it is possible to draw the conclusion that electric-field strength up to 2/3 distance from the electrode center is homogenous.At the edge of the electrode,an inhomogeneous electric field appears which leads to a significant increase in electric-field strength.This increase can,together with the reduction of dielectric strength after activation of a GDA due to the heating of gas during the burning of the electric arc,lead to reignition of the GDA