The AC Transformer and Remote Control Panel are to be used for the electrolytic coloring process of aluminum. This is possible by means of the operator panel, which is able to preset to different coloring programs. Within each coloring program, the required ramp time, coloring time, and process voltage can be easily preset by the corresponding value and timer through the remote control panel. The power circuit features a stepless adjustment of the AC wave form through a motorized variable ratio transformer.