SELECTIVE DEVICE FOR DETERMINING SINGLE-PHASE CLOSINGS IN CABLE LINES Russian patent published in 2008 - IPC G01R31/02 

FIELD: measuring technique.

SUBSTANCE: device can be used for finding cable connection where single-phase ground closing happened in three-phase cable circuit. Selective device for finding single-phase closings in cable lines has N measuring channels. Any channel has zero sequence current transformer connected in series with input of multiplexer, analog-to-digital converter connected with inputs of two meters - amplitude meter composed of AP-filter connected in series with averaging adder, online memory unit, maximum selecting unit and phase meter composed of band pass filter connected in series with phase-sensitive unit, online memory unit and unit for finding number of channel where phase changed, which unit has to be output of phase meter. Device also has phase meter, OR gate, unit for finding number of section and logic processing unit. All the members are connected in a proper way.

EFFECT: improved truth of selective finding.

3 cl, 10 dwg