US Patent 7038125 Low-frequency de-icing of cableways

Low-frequency AC power in a range of about from 50 to 200 Hz flows through a cableway, providing 5 to 100 watts per meter of cableway. Through separate connections to a power bus, a cableway is electrically divided into branches of a parallel circuit that use low voltage to heat. A transformer connected to each branch transforms high-voltage low amperage current to low-voltage high amperage current.