Household appliance, having a first power supply unit, which generates electrical power intended for the operation of the household appliance from a supply AC voltage (Ua) provided by a supply network, at least one controllable power switch (RL, RN), by means of which the first power supply unit can be optionally connected to the supply network and disconnected from the supply network, and a voltage measurement apparatus for determining a voltage value (Us) from the supply AC voltage (Ua), wherein the household appliance is configured to automatically disconnect the first power supply unit from the supply network by actuating the at least one power switch (RL, RN) if it has been ascertained by the voltage measurement apparatus that the voltage value (Us) determined from the supply AC voltage has reached or exceeded a predefined threshold value and wherein the voltage measurement apparatus is connected to the supply network in parallel with the first power supply unit, wherein the voltage measurement apparatus is connected to the supply network via a second power supply unit and the second power supply unit has a bridge rectifier, which is connected to the supply network, and a DC voltage converter, which is connected on the input side to the bridge rectifier and on the output side to the voltage measurement apparatus, the household appliance being characterised in that a voltage measurement circuit, which is connected on the output side to the voltage measurement apparatus, is connected to a part of the DC voltage converter which lies at a voltage level that is inverted compared to the bridge rectifier output voltage. a first power supply unit, which generates electrical power intended for the operation of the household appliance from a supply AC voltage (Ua) provided by a supply network, at least one controllable power switch (RL, RN), by means of which the first power supply unit can be optionally connected to the supply network and disconnected from the supply network, and a voltage measurement apparatus for determining a voltage value (Us) from the supply AC voltage (Ua), wherein the household appliance is configured to automatically disconnect the first power supply unit from the supply network by actuating the at least one power switch (RL, RN) if it has been ascertained by the voltage measurement apparatus that the voltage value (Us) determined from the supply AC voltage has reached or exceeded a predefined threshold value and wherein the voltage measurement apparatus is connected to the supply network in parallel with the first power supply unit, wherein the voltage measurement apparatus is connected to the supply network via a second power supply unit and the second power supply unit has a bridge rectifier, which is connected to the supply network, and a DC voltage converter, which is connected on the input side to the bridge rectifier and on the output side to the voltage measurement apparatus, the household appliance being characterised in that a voltage measurement circuit, which is connected on the output side to the voltage measurement apparatus, is connected to a part of the DC voltage converter which lies at a voltage level that is inverted compared to the bridge rectifier output voltage.