sanyo denki has developed and released the “san ace pwm controller,” a device for controlling the rotational speed of fans that have pwm control function.  

it optimally controls the fan rotational speed easily, contributing to reducing the system power consumption and the fan noise.

among its features:

reduces system power consumption and fan noise - for pwm fan speed control, a pwm control circuit needs to be newly designed and configured. by using this product, however, pwm control function fans can be fully utilized without the need for preparing new circuits, contributing to reducing the system power consumption and the fan noise.

can be common-powered by the fan power supply - the controller can be powered by the fan power supply of rated voltage 12, 24, and 48 vdc, and no separate supply is required.

maximum of four fans connectable - up to four fans with pwm control function can be connected and controlled.

pwm control function allows for the fan speed to be controlled externally by adjusting the duty cycle--pulse width--of input pulse signals. many of our conventional fans are equipped with the function. the controller can only be used on fans with 25 khz pwm input and vih of 3.3 or 5 vdc.