FIELD: electric instruments. SUBSTANCE: method involves weight processing of high harmonics of capacitance current using characteristics of cable lines. Weight digital filtering results in 10-15 percent improvement in probability of correct detection of single-phase short circuits. Device has zero sequence current transformer, matching circuit, spectral processing unit, amplitude detectors, indication unit, current relay, two multiplexers, analog-to-digital converter, weight adder, demultiplexer, code selection unit, gate circuit, threshold gate and cu and control unit. EFFECT: increased efficiency of detection. 3 cl, 7 dwg
