Abstract: Disclosed is a system for ohmic heating of a fluid which includes at least one chamber for receiving the fluid and at least two units each including at least one electrode. Each of the at least one electrode is associated to at least one device for galvanic separation. The electrodes of each of the two units are disposed in the chamber at a distance apart from one another and the device for galvanic separation is disposed outside of the chamber. The system also includes at least one frequency inverter that is electrically connected to the at least two electrode-units for operating the at least two electrode-units.