Limitation of the drop in starting voltage in the electrical system of a motor vehicle

The power supply has a power resistor connected to a starter (3) as a series resistor (42) for limiting current to the starter so that voltage drop of a battery (1) is limited in a switch-on condition of the starter. A switch (52) bridges the series resistor for terminating the limitation of the current to the starter. A control unit adaptively controls the switch based on an actual condition of the battery for bridging the series resistor. The control unit evaluates the actual condition of the battery based on an operating parameter i.e. battery voltage (Ukl30), of the power supply. An independent claim is also included for a method for controlling battery voltage in a power supply of a motor vehicle.