Delta’s new PWM (pulse-width modulation) regulates the voltage signal between fully on and fully off, controlling the speed of a fan. The PWM function is commonly used in OEM cases. Delta also provides standard PWM through distribution channels. Delta’s internal PWM signal control fans deliver a variety of advantages over external PWM controlled devices, such as wide PWM frequency range input (30Hz- 30kHz), lower vibration at lower duty cycle, spike current on fan speed control prevention, better motor efficiency, and lower fan switching noise.
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