A power distributor, in particular for an on-board network of a motor vehicle, has an intermediate tap, two power outputs, and one each switching unit for each power output. A switch is provided for a need-based blocking of the associated power output. Each of the switching units is designed in such a way that a blocking of the associated power output takes place, if, in the event a voltage drop at the associated power output and/or at the intermediate tap below a first setpoint value, an error case is determined. The greater the corresponding voltage drop, the faster the blocking of the associated power output takes place.