In this study, ignition experiments were conducted with XLPE insulators in cables according to the electrodes’ forms (a flat electrode and a round electrode) while generating a 100 W–class direct current (DC) arc. The experiments generated series arcs by applying the newly revised standard UL 1699B. Arcing current and arcing voltage were measured through experiment. The ignition time was compared according to electrode forms using measured data, and the reliability analysis on the arc duration was conducted using a statistical analysis program. Afterward, analysis results were depicted with cumulative density function and probability distribution diagrams to check the distribution patterns, and the time to reach ignition was exhibited using statistical values according to percentiles. The integrated probability distribution diagram can be said to be the result of reflecting a variety of wire forms where the DC arc generation wires were placed in photovoltaic equipment.