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DC12V Japan Nidec Super high speed fan 4056 Server Cooling High Speed ??Brushless Cooling Fan
Brand new original Japanese Nidec supercharged cooling fan, 
specification 40*40*56 MM, is composed of two small fans, fan 1 is DC12V 1.32A, fan 2 is DC12V 1.91 A, It seems small but powerful. It is supplied by the small fan in the front, and the small fan in the back is pressurized again. With high air volume and high wind power, the front fan has reached 19200 rpm, and the rear booster fan has a speed of 17,400. The speed of the fan is super high. The speed of the B fan has reached more than 23,000 rpm. The wind sound of the whole fan at full speed is like a whistling north wind. Just listening to this sound will know that this small fan is really powerful.


        Moreover, the two small fans are all imported high-speed bearings and brushless motors. They have a long lifespan. These babies are very rare and good ones, and they are generally used in high-end servers as cooling fans. 


1. For simple operation, connect the red wire to the positive pole of the power supply, and the black wire to the negative pole of the power supply. When DC12V, the fan runs at the highest speed. The front fan of the A fan is 19200 rpm, the rear fan is 17400 rpm, and the B fan The speed has reached more than 23,000 revolutions, so that the voltage can be adjusted to adjust the speed. This batch of wind has the protection of reverse connection of positive and negative electrodes.


       2. If you need to use PWM to adjust the speed, connect the PWM signal wire to the blue wire. The ground wire of PWM should also be connected to the negative pole of the power supply (black wire). The positive pole of the power supply is still connected to the red wire. The pulse frequency needs to be 500HZ. Above, then adjust the duty cycle to adjust the fan speed (20%-99% adjustable).


Duty cycle 20% Front fan 3470 rpm, rear fan 3260 rpm Current: 0.11 A


Duty cycle 30% Front fan 5500 rpm, rear fan 5000 rpm Current: 0.14 A


Duty ratio 40% Front fan 7600 rpm, rear fan 7000 rpm Current: 0.22 A


Duty cycle 50% Front fan 9600 rpm, rear fan 8600 rpm Current: 0.29 A


Duty ratio 60% Front fan 11,500 rpm, rear fan 10,000 rpm Current: 0.4 A


Duty cycle 70% Front fan 13600 rpm, rear fan 12000 rpm Current: 0.55 A


Duty ratio 80% Front fan 15600 rpm, rear fan 14000 rpm Current: 0.72 A


Duty ratio 90% Front fan 17600 rpm Rear fan 15700 rpm Current: 0.95 A


Duty ratio 99% Front fan 19200 rpm, rear fan 17400 rpm Current: 1.25 A


        Its label is DC12V1.32A, the measured maximum current is 1.25 A, the front fan speed has reached 19200 rpm, and the rear fan has reached 17400 rpm. The sound at full speed is like the whistling north wind. The wind of this small fan is so powerful People were surprised. Please pay attention to safety when using it. With such a fast speed, the blade is as dangerous as a flying knife. Please do not touch it! ! !


Fan weight: 97 grams


      A fan is more energy-efficient than B fan, but B fan is more powerful than A fan: