FIELD: measuring equipment.
SUBSTANCE: invention relates to electrical measuring equipment and relay protection. The method consists in measuring the leakage current from the auxiliary test voltage source in the form of a periodic pulse sequence, the test voltage is connected through a resistor star to the phases of the monitored network, the leakage current is measured by measuring the voltage drop u(t) on the measuring resistance connected in series with the test voltage source, a signal delayed relative to the voltage drop on the measuring resistance by an interval T/2 is formed, the delayed signal is subtracted from the voltage drop on the measuring resistance, the resulting signal um(t) therein is converted by means of correction into a signal uc(t), the running average of the signal uc(t) is calculated on an interval equal to the period Tc of the voltage of the monitored network, the insulation resistance is calculated.
EFFECT: increase in the safety on double-current type electric networks with an insulated neutral.
1 cl, 7 dwg
