PROCEDURE TESTING RESISTANCE OF INSULATION AND PROTECTION OF ELECTRIC NETWORK

摘要

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 <EMI ID=0.1 HE=28 WI=63 TI=CHI> 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 <EMI ID=0.2 HE=12 WI=35 TI=CHI>, comparison of obtained value with two settings R1 and R2, N1 repetition of measurements with rins < R1 and n2 repetition of measurements with R1 < rins < 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