A tap changer in which a pair of selector contacts can be jointly movable or individually movable to engage stationary tap contacts of an array and one of the selector contacts is in series with a tickler coil and switchover resistor connected to one fixed contact of a bypass switch whose movable contact is connected to the load. The other selector contact is connected to one stationary contact of a switchover switch whose movable contact is connected to a second contact of the bypass switch while another contact of the switchover switch is tied to a point between the tickler coil and the resistor. A pair of oppositely poled parallel thyristors bridges the auxiliary network of the tickler coil and resistor and the main branch passing from the switchover switch to the bypass switch. The movable contacts are operated by an intermittent drive of the Geneva mechanism type.