The invention relates to an electrophoretic dipping
system comprising at least one dipping bowl (1) which can be filled with a liquid and an object which is to be coated and which can be dipped therein. At least one
power supply unit (5A, 5B, 5C) produces
DC voltage with definite residual
ripple from AC
voltage. The one pole thereof can be connected to at least one
electrode of a first polarity (3A, 3B, 3C), said
electrode being arranged in the dipping bowl (1) and the other pole thereof can be connected to the object which is to be coated. The
power supply unit (5A, 5B, 5C) comprises one uncontrolled
diode rectifier bridge (19) and an IGBT switch (22) which comprises a controllable oscillator (24) and a power
transistor (23). The controllable oscillator (24) generates pulses having a repetition frequency
ranging from between 5 and 30 kHz with variable pulse widths. The power
transistor (23) is controlled by said pulses. The
voltage pulses produced therefrom can be smoothed out with the aid of relatively small
smoothing elements until a highly reduced residual
ripple which benefits the quality, especially the smoothness and the roughness of the applied protective
coating is obtained. Said
power supply unit (5A, 5B, 5C) also has a highly improved cos Phi compared to currently known
thyristor bridge switches used for the same purpose.