The invention relates to a drum, comprising - a wall, wherein at least the inside of the wall is provided with a surface of insulating material, - an opening, defined by wall segments, radially spaced from one another with respect to a central rotational axis of the drum, and - a drive mechanism for rotating the drum in a first or in a second direction, characterized in that - at least one first electrode is arranged on the inside of the wall, and in that - at least one counter electrode is arranged on or between a central axis of the drum and its wall, and a method for coating workpieces.