The Influence of Contaminated Copper Wires on the DC Joule Heating of Connectors

The production process of wires involves different processing agents which can lead to a contamination of the conductor surface. As a result the contact resistance and Joule heating may increase. In contrast to bulk wires stranded wires have many inner contact points, wherefore contaminations are especially critical. In this work contaminations on wires are investigated with optical light spectroscopy and infrared spectroscopy. To quantify the contact quality of stranded wires a device is developed for measuring the cross-sectional resistance. Wires with good and poor contact qualities are used to investigate the impact of contaminations on the contact resistance and the Joule heating of wire connectors.