PROCEDURE TESTING RESISTANCE OF INSULATION AND PROTECTION OF ELECTRIC NETWORK Russian patent published in 2000 - IPC

FIELD: electric measuring technology, relay protection of power supply systems. SUBSTANCE: procedure is based on measurement of leakage current from auxiliary source of measurement voltage in the form of periodic sequence of pulses of type specified below and includes measurement of leakage current I₁ in time interval T <t <2T and leakage current I₂ in time interval 3T < t <4T by integration of voltage drop across standard resistance during period of feeding network, computation of resistance of insulation by formula , comparison of obtained value with two settings R₁ and R₂, N₁ repetition of measurements with r_ins < R₁ and n₂ repetition of measurements with R₁ < r_ins < R₂ and de-energizing of network in case of sequential verification of fact of decrease of resistance of insulation by n₁ or n₂ times. EFFECT: enhanced noise immunity of measurement of resistance of insulation and reliability of protection of power supply systems. 4 dwg