A method of maintaining a supply of power to a load comprising operating a power generator connected to a mains voltage in a rated operating mode, generating a power signal by the power generator, feeding the power signal to the load, monitoring the mains voltage or a variable derived therefrom for an occurrence of a first specified event, and operating the power generator in a first predefined operating mode based on the occurrence of the first specified event, wherein the first predefined operating mode differs from the rated operating mode.