can i use an ac adapter to run dc fans????

[shawnz28]

This may be a stupid question but here it goes. I am building a new canopy for my reef aquarium and want to use some of these in it for airflow on the metal halides since they are quite http://www.pcmods.com/details.asp?ProdID=596 . Basically I want to know if I can just splice a simple ac adapter to 2 or 3 of these or is there some reason I cannot?

 

[LordMorpheus]

any adapter will make the fans spin. If the fans are not of the permanent magnet variety, they will spin with AC power, although you don't want to be applying 120V to 12V fans . . .

So, just go through all those adapters you have (all over the place, anything you plug in that is a bigheavy weight instead of just a pair of prongs) and read the fine print till you find one that has an output of around 12vdc (doesn't have to be exact, 10 will work, 14 will make them loud and they may fail before they warrantee is over, but it'll make em push air) and wire them up. make sure you wire them in parallel. If you don't know what that means you shouldn't be messing with this stuff.

Or, you could just take an old power supply (i know youve got some) and play with the big mobo thing by connecting pins (make sure you are well insulated, 12V is enough to sting) until you find the right ones to turn the supply one, and then just use them normally. Or you could poke around online until you find a diagram of with wires to bridge to bring an ATX power supply to life.

 

[MithShrike]

IDK... Perhaps. If there is one that you're willing to test go ahead. My friends and I would fry fans in our computer repair class by taking the cord that goes into the back of a computer and the undoing the wires in a case fan and stick it in the cord and then plug it in. Much fun

 

[MournSanity]

Originally posted by: LordMorpheus
any adapter will make the fans spin. If the fans are not of the permanent magnet variety, they will spin with AC power, although you don't want to be applying 120V to 12V fans . . .

So, just go through all those adapters you have (all over the place, anything you plug in that is a bigheavy weight instead of just a pair of prongs) and read the fine print till you find one that has an output of around 12vdc (doesn't have to be exact, 10 will work, 14 will make them loud and they may fail before they warrantee is over, but it'll make em push air) and wire them up. make sure you wire them in parallel. If you don't know what that means you shouldn't be messing with this stuff.

Or, you could just take an old power supply (i know youve got some) and play with the big mobo thing by connecting pins (make sure you are well insulated, 12V is enough to sting) until you find the right ones to turn the supply one, and then just use them normally. Or you could poke around online until you find a diagram of with wires to bridge to bring an ATX power supply to life.

What would happen if you feed a 12v fan 120v?

 

[LordMorpheus]

120V to a 12V fan.

well, the coils inside would probably melt their insulation and fuse together, so nothing except for a destroyed and stinking fan, possible housefire, and popping your breaker.

Assuming the wires didn't melt, it would spin way, way faster than it was designed to and would probably break apart.

But most electric motors are permanent magnets, as i recal, so it would not spin under AC power, it would just twitch and melt and destroy anything nearby (not really) and pop whatever breaker its on . . . . so I would suggest you go with an AC-DC adapter.

 

[arcas]

Why not just buy 120mm fans that are designed to operate on 120VAC? They're a little more expensive than 12VDC fans but not by much. Around $8-$15 each at places like excess-solutions.com or mpja.com but check other surplus shops to see if there are any better prices. Given that you're playing with expensive metal halide lights, I suspect an extra $4 per fan isn't going to break the bank. The time you save by not having to buy/build a voltage regulator/rectifier for 12VDC fans would be well worth it.

 

[LordMorpheus]

Originally posted by: arcas
Why not just buy 120mm fans that are designed to operate on 120VAC? They're a little more expensive than 12VDC fans but not by much. Around $8-$15 each at places like excess-solutions.com or mpja.com but check other surplus shops to see if there are any better prices. Given that you're playing with expensive metal halide lights, I suspect an extra $4 per fan isn't going to break the bank. The time you save by not having to buy/build a voltage regulator/rectifier for 12VDC fans would be well worth it.

yah, thats probably the smart way . . . but its not as much fun! hehehehe

I'd say do it his way. If it was me, I'd go through my old adapters, but most people think I'm crazy anyway.

 

[Shawn]

Originally posted by: hypersonic5

Originally posted by: LordMorpheus
any adapter will make the fans spin. If the fans are not of the permanent magnet variety, they will spin with AC power, although you don't want to be applying 120V to 12V fans . . .

So, just go through all those adapters you have (all over the place, anything you plug in that is a bigheavy weight instead of just a pair of prongs) and read the fine print till you find one that has an output of around 12vdc (doesn't have to be exact, 10 will work, 14 will make them loud and they may fail before they warrantee is over, but it'll make em push air) and wire them up. make sure you wire them in parallel. If you don't know what that means you shouldn't be messing with this stuff.

Or, you could just take an old power supply (i know youve got some) and play with the big mobo thing by connecting pins (make sure you are well insulated, 12V is enough to sting) until you find the right ones to turn the supply one, and then just use them normally. Or you could poke around online until you find a diagram of with wires to bridge to bring an ATX power supply to life.

What would happen if you feed a 12v fan 120v?

try it and make sure to take some pics!

 

[LordMorpheus]

Originally posted by: iloveme2

Originally posted by: hypersonic5

Originally posted by: LordMorpheus
any adapter will make the fans spin. If the fans are not of the permanent magnet variety, they will spin with AC power, although you don't want to be applying 120V to 12V fans . . .

So, just go through all those adapters you have (all over the place, anything you plug in that is a bigheavy weight instead of just a pair of prongs) and read the fine print till you find one that has an output of around 12vdc (doesn't have to be exact, 10 will work, 14 will make them loud and they may fail before they warrantee is over, but it'll make em push air) and wire them up. make sure you wire them in parallel. If you don't know what that means you shouldn't be messing with this stuff.

Or, you could just take an old power supply (i know youve got some) and play with the big mobo thing by connecting pins (make sure you are well insulated, 12V is enough to sting) until you find the right ones to turn the supply one, and then just use them normally. Or you could poke around online until you find a diagram of with wires to bridge to bring an ATX power supply to life.

What would happen if you feed a 12v fan 120v?

try it and make sure to take some pics!

not much to see. Smoke, scorch marks, and a really, really bad smell . . which a camera cant capture anyway.

 

[MournSanity]

That's completely awesome. I have to try that some time.

 

[MournSanity]

Originally posted by: iloveme2

Originally posted by: hypersonic5

Originally posted by: LordMorpheus
any adapter will make the fans spin. If the fans are not of the permanent magnet variety, they will spin with AC power, although you don't want to be applying 120V to 12V fans . . .

So, just go through all those adapters you have (all over the place, anything you plug in that is a bigheavy weight instead of just a pair of prongs) and read the fine print till you find one that has an output of around 12vdc (doesn't have to be exact, 10 will work, 14 will make them loud and they may fail before they warrantee is over, but it'll make em push air) and wire them up. make sure you wire them in parallel. If you don't know what that means you shouldn't be messing with this stuff.

Or, you could just take an old power supply (i know youve got some) and play with the big mobo thing by connecting pins (make sure you are well insulated, 12V is enough to sting) until you find the right ones to turn the supply one, and then just use them normally. Or you could poke around online until you find a diagram of with wires to bridge to bring an ATX power supply to life.

What would happen if you feed a 12v fan 120v?

try it and make sure to take some pics!

I did! Heres a pic I took before my skin melted off:

BOOM!

 

[shawnz28]

The main reason I was thinking of trying this DC fan route is that I am having a little trouble finding a AC fan that is quite yet pushs a good amount of air which one like I posted the address for accommodates both of these wants. But I just might not be looking hard enough yet.