A multi-phase alternating current (AC) arc has been applied to glass melting technology. The large volume discharge produced by a stable multi-phase AC arc is preferable to melt the granulated glass materials. The discharge behavior and the high-temperature region of the plasma can be controlled by the electrode configurations. In this study, the spatial characteristics of the arc discharge were examined by image analysis of high-speed camera. Results show arc existence area is related with electrode configuration. This study provides the useful information of efficient particle treatment in the preferred electrode configuration. However, the electrode erosion is one of the most considerable issues to be solved. The combination of high-speed video camera and band-pass filters was introduced to measure the electrode temperature to investigate the erosion mechanism of the multi-phase AC arc. The dynamic behavior of the electrode vapors in the arc was investigated by using the same high-speed camera system. Results show the tungsten electrode mainly evaporates at the anodic period during AC cycle.