The Influence of Handling Stress on Transmission Line Parameters of Copper Twisted Pair Cables

A method of analyzing the influence of handling stress on transmission line parameters: resistance, inductance, capacitance and conductance (RLCG) of copper twisted pair cables (CTPCs) is presented. The RLCG parameters were computed from their measured impedances across the length rather than the frequency as used in most literature. This is to enable the examination of the characteristics of transmission line parameters across their lengths which can help determine the physical integrity of the cables. This method of analyzing the characteristics of RLCG parameters is very important because cables could be manipulated during installation in the form of repeated coiling and uncoiling. Handling stress during installation can cause degradation in CTPCs especially if they are non-standards compliant. One such substandard cable is the copper-clad aluminum (CCA) cable often displayed as category-rated cables. In this research, four category 6 CTPCs were selected randomly from the market. One of the cables selected for examination is the CCA cable. The four CTPCs were subjected to three rounds of coiling tests to imitate the anticipated handling stress during installation. The impedances of the CTPCs across the length were collected for the three rounds of tests. The RLGC parameters were computed from the measured impedances of the cables with the aid of Matrix Laboratory (MATLAB). The results obtained indicate that the CCA cable gave the worst resilience to the handling stress as it presented the highest changes in RLCG across the length of the cable in all four pairs. On the other hand, cable 4 gave the best resilience to the handling stress test in all four pairs. The method can be used by cable engineers and installers to analyze the characteristics of transmission line parameters due to handling stress anticipated during installation before deployment. The technique can also aid the determination of the physical integrity of CTPCs which can help minimize the risk of degradation that can lead to performance problems in networks.