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Topic: Testing Motor Shield with CPU fan motors? (Read 1 time) previous topic - next topic


PC fans rotate in one direction only; they are essentially BLDC motors with the controller built into the motor itself. The coils are fixed on a small PCB (which also has the driver circuitry on it), and the fan hub has a round, polarized ring magnet that fits around the coils and spins. If you reverse the polarity of the input voltage on the fan, it will just sit there (and if the fan is cheap enough, the magic smoke will be released). The only thing you can do with these fans is (in general) turn them on or off (using a relay or transistor), and you can vary the speed of the fan by varying the voltage (PWM or otherwise), within a certain limit (you should not exceed the rated voltage to try to make such a fan spin faster, as you will likely burn out the control electronics; you can however apply lower voltages down to a certain limit to make it spin slower).
I will not respond to Arduino help PM's from random forum users; if you have such a question, start a new topic thread.


Now that you mention it, what is the H-drive?  What is a H - Bridge? :smiley-zipper:

It's a circuit designed to power and control a motor so that it can be commanded to turn in either direction and at variable speed. It's an interface shield board or module that wires between an arduino controller and the higher voltage and current motor and it's power source.



for my cpu fan that just has red and black wires, which pin(s) would I plug them into?  How do I access the screw terminal ports?  I only see the function Stepper myStepper(stepsPerRevolution, 8,9) for this two wire example. 


All I read is:

Stepper(steps, pin1, pin2)


steps: the number of steps in one revolution of your motor. If your motor gives the number of degrees per step, divide that number into 360 to get the number of steps (e.g. 360 / 3.6 gives 100 steps). (int)

pin1, pin2: two pins that are attached to the motor (int)


as far as i know, a pc fan only rotate in one direction, using a H Bridge would be a waste. Just use a transistor or a mosfet to control your pc fan. Just use the analogWrite to control the motor speed. Btw pc fan is not a stepper motor.

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