FIELD: electrical engineering, in particular, devices for compensation of capacitance currents of single phase ground for insulated neutral wire main with 5-35 kV. SUBSTANCE: device provides measurement of mains phase capacitance for subsequent resonance tuning of arc-quenching reactors. Goal of invention is achieved by inducing artificial potential of non-standard frequency on neutral wire using periodic discharge to signal winding of charged capacitor. Signal, which is proportional to capacitance of phases of mains with insulated neutral wire, is produced by means of amplitude detector at output of differentiating circuit, which is connected to output of voltage transformer winding, which is connected as open delta connection. EFFECT: increased precision of measurements, simplified measurement, decreased power consumption in power supply circuits. 2 cl, 1 dwg
