Electrical contacts are separated at a constant opening speed in a 48VDC/50A-600A resistive circuit. Break arcs are observed using two high-speed cameras from the top and side directions. Lengths of the break arcs are analyzed from images taken by the cameras. Arc voltages and currents corresponding to the analyzed arc lengths are investigated to obtain voltage-current characteristics of the break arcs. Relationships between the arc length versus gap voltage and the arc length versus circuit current are obtained. These results are slightly scattered. Therefore, to obtain one-to-one relationships between the arc length and the gap voltage, approximate curves should be determined for these results. Using these approximate curves, eventually, the voltage-current characteristics for each arc length are indicated.