Emission profiles of torch generated plasmas

Emission spectroscopic techniques are employed to investigate and characterize the spectral output from a 75-kW dc arc. Torch parameters such as stability, temperature, and electron density were determined. After initially characterizing and optimizing the system, we investigated the composition of plasma spectral emissions with the intent of designing and testing a novel electrode health monitor. A prototype device was built and tested. The results presented clearly demonstrate that such a device is capable of providing early warning of impending electrode failure and has the potential of playing a significant role in system control and maintenance. (Author)