Tower cooling power supply

[dixe134]

I have 4 possible power supply options on hand currently for my tower cooling project.I have purchased a blower specifying -12v 700 ma..I have a cell charger4.4v 1.5 amp---ANOTHER 12 V 200 MA POWER SUPPLY---AND A THIRD 9V-210 MA POWER SUPPLY,and finally a 13.8v-1.5amp portable radio battery charger. The fan is rated at 25 cfm i know that is way more than i need to cool the tower.Which of my power supply's will work better for this application? Thanks for your help.

[jaeckleint]

Originally Posted by dixe134

I have 4 possible power supply options on hand currently for my tower cooling project.I have purchased a blower specifying -12v 700 ma..I have a cell charger4.4v 1.5 amp---ANOTHER 12 V 200 MA POWER SUPPLY---AND A THIRD 9V-210 MA POWER SUPPLY,and finally a 13.8v-1.5amp portable radio battery charger. The fan is rated at 25 cfm i know that is way more than i need to cool the tower.Which of my power supply's will work better for this application? Thanks for your help.

The 4.4 volt will not spin the fan, the next 2 at 200ma and 210 ma do not have the current and will overload or burn out because you need at least 700ma @ 12 volts. The battery charger is not rated for continuios duty but has the needed current and volts. So I would say none of the above.

[jumper]

A switching power supply is a switching power supply... the charger will work fine at 700mA, probably as long as the fan will last. This is also assuming you're not running it right at the upper edge of its limit, which you're not. You'll spin the blower motor a little faster at 13.8V (unless it has a built in current limiting resistor as some do) but it won't hurt it.

You could probably spin a motor that small with the lower voltage supplies but not enough to push the air all the way up the tower. I've got a potentiometer on my blower so I can vary the fan speed, I'm at around 8.5 volts to get the air flow/noise level I want. You might want to look into that if you plan to use the bigger power supply.

Of course you should disregard the 2 that have such low current ratings, they'll fold back and fail quickly trying to push the motor.

[jeffie45]

The fans I used were 12v and 300ma per fan (approx). and I use 2 fans..
I found a 12v 1000ma supply (linksys power supply from a router) and it is fine.. or you can go to radio shack and get one I think up to 1000 ma.. or maybe more or less depending on the fan your using. Now my Kegerator is pouring nice cold beer... so look at the fan first make sure it is not going to pull more than your power supply will handle.. PC fans (80 or 92mm) are around 300ma

[dixe134]

I got my blower yesturday and i tried all the power supplys.The 12v-200ma seemed to run the blower well.I am sure it is not running it at top speed but it moved alot of air.Blower is a nidec gaMMA 30 MODEL A34124-16 12 V DC .---.65 AMP IS WHAT"S ON THE BLOWER.Will the power supply run it ,just not as fast , or will it die soon after i put it in service?Thanks for your time.

[cubby_swans]

Originally Posted by dixe134

I got my blower yesturday and i tried all the power supplys.The 12v-200ma seemed to run the blower well.I am sure it is not running it at top speed but it moved alot of air.Blower is a nidec gaMMA 30 MODEL A34124-16 12 V DC .---.65 AMP IS WHAT"S ON THE BLOWER.Will the power supply run it ,just not as fast , or will it die soon after i put it in service?Thanks for your time.

The power supply is likely to overload and die. You're asking a 200mah power supply to put out 650mah (.65Amp).

[jeffie45]

I would try to find a 1 amp power supply at least.. I am using computer fans for mine.. (that is what I had laying around.. and they are usually cheap..)
Just need to get air moving.. that makes a huge difference.