Motor-protection filters from MTE Corp., Menomonee Falls, Wis., reduce peak voltage and operating temperatures. The filters are available in open and closed models and protect motors from 1 to 600 hp. The filters convert PWM output to a near sinusoidal waveform using the LC low-pass filter technique. Motors are protected from failure resulting from high peak voltage, fast dv/dt rate, or insulation breakdown from high-operating temperatures.