Plasma cutting is a melting process in which a jet of ionised gas at temperatures above 20,000°C is used to melt and expel material from the cut. During the process, an electric arc is struck between an electrode (cathode) and the workpiece (anode).
A constant current DC power source is used as the power supply for plasma cutting. The output current of the power supply is what determines the speed and cut thickness capability of a plasma cutting system.