Impedance-Based Short Circuit—Short Circuit Fault Location Method in Coaxial Cables

Abstract

The paper presents the results of the assessment and verification of a non-destructive method of fault location in coaxial cables with a local weakening of insulation. The essence of the method is to measure the input impedance of the cable in a short circuit at both ends and, based on obtained values, to determine the transverse impedance of the fault and the distance to the fault location. For the RG59 Cable with a length of 50.0 m, with the assumed distance to the fault location of 5.0 m, for the short circuit-short circuit method, the error in determining the fault location is from 0.0 m to 1.8 m, for open circuit-open circuit from 0.1 m to 0.2 m and open circuit-short circuit to 0.2 m. For the RG59 Cable at the actual distance to the fault location of 10.0 m, for the short circuit-short circuit method, the error in determining the fault location is from 0.0 m to 0.7 m, for open circuit-open circuit from 0.0 m to 0.1 m and open circuit-short circuit from 0.2 m to 0.7 m. For the RF-7 Cable with a length of 100.0 m, with the assumed distance to the fault location of 10.0 m, for the short circuit-short circuit method, the error in determining the fault location is from 0.7 m to 1.8 m, for open circuit-open circuit from 0.0 m to 0.7 m and open circuit-short circuit 0.2 m to 2.3 m. For the RF-7 Cable with the assumed distance to the fault location of 20.0 m, for the short circuit-short circuit method, the error in determining the fault location is from 0.1 m to 1.2 m, for open circuit-open circuit method from 0.1 m to 0.3 m and open circuit-short circuit method from 0.1 m to 0.7 m.

Keywords

• Input impedance
• transverse impedance
• distance to the fault location
• coaxial cable
• diagnostic tests