I have some 12V brushless cooling fans here (the kind to cool computers) and a 24V battery. I don't have enough money to dedicate a switching DC-DC converter just for the fans, but I lose a ton of power by hooking each fan in series with a resistor to step down the voltage.
I was thinking about connecting the fans in pairs to get 12V across each fan to reduce parts and conversion losses. But I am not entirely sure how a brushless fan works. I think they have built in electronics to commutate the brushless motor (that are so integrated I can't tell where they are) because I can just plug the motor into a DC source and it will run.
Will the electronics in the high-side fan function properly? The high-side fan's ground becomes the low-side fan's voltage input and I can't guess what will happen.
I was thinking about connecting the fans in pairs to get 12V across each fan to reduce parts and conversion losses. But I am not entirely sure how a brushless fan works. I think they have built in electronics to commutate the brushless motor (that are so integrated I can't tell where they are) because I can just plug the motor into a DC source and it will run.
Will the electronics in the high-side fan function properly? The high-side fan's ground becomes the low-side fan's voltage input and I can't guess what will happen.
Last edited: