DETECTION OF DISCONNECTED POINT FOR LINES USED IN GROUND CONTROLLED APPROACH SYSTEM

摘要

PURPOSE:To enable the specifying of a disconnection point at a high accuracy with an in expensive device, by a method wherein wires are grounded through a variable resistor except for those with disconnection and a detector is moved along a cable with the application of AC to the disconnected wires. CONSTITUTION:When one of paired wires of an IR cable in the overall length of 450m is disconnected, wires of the IR cable 11 are grounded at one end thereof through a variable resistor 12. Then, AC 14 of 100V is applied to a wire 13 disconnected at the other end thereof and a resistance value is measured as border between that at which a lamp of a highly sensitive detector lights continuously and that at which it does not to adjust a resistance value of the variable resistor 12 moving the highly sensitive detector with an access along the surface of the IR cable 11 so as to be slightly larger than the measured value. Then, a disconnection point is specified from the border 15 between a lighted point and extinguished point of the lamp while moving the highly sensitive detector along the IR cable.