FIELD: electric measurement technology. SUBSTANCE: method involves superposition of varying-polarity A C measuring voltage onto line under measurement whereupon D C component of current through circuit of D C measurement voltage source is measured upon end of transient process; then insulation resistance is calculated. Transient process is ceased without waiting for its completion and then D C component of voltages across insulation impedance and mentioned current are measured and insulation resistance value is found from equation given in description of invention. EFFECT: improved measurement accuracy. 3 cl, 2 dwg
