A process for superimposing AC over DC, which feeds a group of electrolytic cells for electrowinning or electrorefining copper and other products, characterized by (a) incorporating an inductor which is connected between the terminals of two consecutive middle cells of the group of electrolytic cells, wherein the inductor functions are to act as a filter for the AC and as conducting means for the DC; (b) incorporating a capacitor connected in parallel to the original DC source, wherein the capacitor functions are to act as conducting means for the AC and as a filter for the DC; and (c) incorporating an AC source connected to the terminals of an inductor installed in the middle point of the group of electrolytic cells.
