PROCEDURE LOCATING CABLE FAULT IN POWER TRANSMISSION AND COMMUNICATION LINE WITH USE OF MARKER'S METHOD AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2003 - IPC

FIELD: instruments locating points of break and short-circuit in power transmission and communication lines and determining their length. SUBSTANCE: sounding pulses are used to act on input of object of measurement, reflected pulses are received and amplified according to inverse law of pulse damping, time of arrival of pulse reflected from point of fault or end of line is recorded and distance to point of fault or to end of line is found by time interval between moments of sounding and arrival of reflected pulse. Heterpolar pulses from break and short-circuit are converted to unipolar pulses, unipolar slowly falling sawtooth voltage is formed, they are registered at moment of equality of converted and sawtooth voltage, reference voltage is formed, reference voltage is converted to shortening voltage, time interval between moment of arrival of reflected pulse and moment of sounding is converted to distance voltage, pulse corresponding to start of measurement period, pulses corresponding to moments of arrival of reflected pulses, pulse corresponding to finish of measurement period are sent with use of additional radio channel. Operator receives over radio channel pulse corresponding to start of measurement period, pulses corresponding to moments of arrival of reflected pulses and pulse corresponding to finish of measurement period by means of radio receiver in information processing unit placed on run of cable line. Sounding pulse is also received with the aid of additional receiver at point of operator's position on run of cable line, is subjected to amplification in accord with inverse law of pulse damping, time of arrival of pulse to receiver is registered and converted to marker, this time is increased twofold, distance to point of operator's position on run of cable line is found by time interval between pulse corresponding to moment of arrival of reflected pulse corresponding to point of fault and marker, distances to point of fault and to operator's position are compared. EFFECT: increased accuracy of location of point of fault, shortened time of search for fault in cables in power transmission and communication lines. 3 cl, 3 dwg