Abstract: The invention relates to a tap changer for the interruption-free switchover between winding taps of a tap-changing transformer. Furthermore, the present invention relates to a novel vacuum interrupter which is particularly suitable for such a tap changer. The tap changer according to the invention is based on the general concept of combining in each case one main contact (V1) and one mechanical switching means (U1), connected in series therewith, of a first load branch and an additional resistive contact (V3) of a second load branch in only a single vacuum interrupter (1) with a common housing (5).

Abstract: At least main electrodes for a low pressure gas discharge arranged at a distance from each other are present in such switches, the main electrodes forming a cathode and an anode of a discharge path in an interrupter chamber for the gas discharge which is fired by increasing electron density in a cathode cavity. For this purpose, at least the cathodes have at least one opening, preferably the cathode and anode, having opposite aligned openings for triggering the discharge. In such an arrangement, an arrangement for the generation of a magnetic field superimposed on the discharge may be present. At least one slot is present in at least one of the main planar electrodes for generating a radial magnetic field. A single slot maybe provided which runs in the form of a spiral from the area of the electrode center to the area of the electrode edge.