12v cooling fans

[mike31154]

Originally Posted by Doug

They say 0.25 A. Whatever that is.

That is 250 milliamps. 0.250, take it to 3 decimal places for milli which means thousandths, which is what the 3rd decimal place designates.... or a quarter of an amp, if you wish. Never a bad idea to get a power supply that has a good buffer of extra capacity (within reason). More efficient and less heat produced by a larger supply running at less than full capacity, than a small one trying to put out its max power. Not to mention, safer.

[subman]

Originally Posted by mike31154

That is 250 milliamps. 0.250, take it to 3 decimal places for milli which means thousandths, which is what the 3rd decimal place designates.... or a quarter of an amp, if you wish. Never a bad idea to get a power supply that has a good buffer of extra capacity (within reason). More efficient and less heat produced by a larger supply running at less than full capacity, than a small one trying to put out its max power. Not to mention, safer.

He only wants to run 2 so thats a 50% buffer thats pretty good

[KrazyKuch]

Originally Posted by banditpowdercoat

Yup, can run 4 .25mA fans. If you want real power, get a old computer power supply. They can power a ton of fans. Plus, you have 12v and 5v and you can mix it to get 7v So, you can run a fan at 7v no problem, little slower, less flow but alot quieter used to do that in my overclocked computers all the time.

In case anyone cares, to turn on a computer Pwr supply, connect the Green wire to ANY black one.
Yellow to Black 12Vdc
Red to Black 5Vdc
Yellow to red, 7Vdc

Ummmm...I have had a couple power supplies were you have had to take the green to ground to make them turn on!!!!

[Doug]

Now that its been running the duel fans, I notice the power supply is fairly warm to the touch. How much would be normal? Cant say as I ever noticed it before when running a single.
Thanks

[banditpowdercoat]

It should be fine, Doug. Power supply's can get warm, as long as its not HOT. If you can hold it, its ok. They usually are designed to burn out before they cause a fire or anything anyways

[Doug]

Thanks Dan. I put a little cooling fan to cool the power supply for the cooling fans.