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Variable speed on a 5v brushless fan Answered

Hi everyone!
I have a 5v DC (0,15A, 50mm x 15mm) computer brushless fan that I want to power with a battery pack (4x AA rechargeables= 4,8v) or the MightyMinty Boost. This small blower is meant to be a part of a woodgas stove, and will bring air to the fire through a small duct.

I'm looking for a circuit that would allow me to control the speed of the fan and the airflow. Kinda like a dimmer switch. Is there a readily available switch or devices that I could plug between the batteries and the fan? I guess the RC guys out there know a few thing about variable speed controller.

I'm a newbie at this; I don't what to build a circuit from scratch, unless it's really simple.



8 years ago

I made a batch of about 25 fan speed controllers for stovers - where are you in the world ? I might be able to send you one.



Reply 8 years ago

They're putting "squirrel cage" style fans in computers now? *shakes head*


Reply 8 years ago

The one shown is a meagre 0.75W.  You should see the ones on some late Pentium 4 Dell PCs - 12V at 2.5A.  That's 30 Watts!!!
When those beasts ramp up to full speed you half expect the machine to come hurtling across the desk at you. 


Reply 8 years ago

I don't know what mine is, but I do know it sure does sound like the a/c unit starting up when the thermostat kicks the fan in .... :-)


Reply 8 years ago

I've seen a few cpu and video card heatsink coolers with those. They seem more low profile to fit on the motherboard or plug in cards. The ducted or hooded fans direct the heat out the back more efficiently.