Sine wave filter Three-phase supply voltage 200-240 V. Sine wave output filter, for frequency converters, for ATV630U15M3 - U30M3 converters, IP 20. Rated current 15 A. The filters operate in a switching frequency range between 4 and 8 kHz. If the filter is used with ATV650U07N4/N4E - D90N4/N4E converters, it must be installed in a separate cabinet to ensure protection class IP 55.