12VDC muffin fan question...

[Soggy Bottom Boy]

Is it possible to "under-clock" a 60mm x 60mm 12v muffin fan by supplying, say, 6 or 7 volts without damaging it? I am thinking that I might want to slow down the CFM to reduce fan noise.

I know that AC motors don't do well with running at low voltage,will heat up, and go TU in a hurry. Will doing this melt something or burn out a 12VDC muffin fan?

[sambedded]

Don't know what is kind of "muffin fan ".you are referring to, but PC 12 V fans can be easily run on lesser voltage.

[janee]

i have a 12 v fan on my controler that i have run for 2 years off a 9 v converter. works fine dosent get hot

[DAD300]

I've used one on a 4volt solar cell as a car cooler...no issue.

[rad14701]

Those fans can be regulated to under half their rated current without issues... That means you can safely run between 6V and 12V, but not much over 12V...

[PhatFil]

fyi i use 12v pumps for moving my brewery liquors about and a 12v pc fan as the basis for my stirplate for building up yeastie starters, both are controlled by really cheap tattoo gun psu's from ebay, circa 10 usd complete with control knob and voltmeter.
u just need to short the footpedal jack and use a 1/4" mono jack to plug your 12v device in..

[Soggy Bottom Boy]

Cool!

Thanks for the replies.

Now, I need to round up a wall wart to do the job. I think that I have about half a junk drawer full of likely candidates.

Thanks again.

[Soggy Bottom Boy]

fyi i use 12v pumps for moving my brewery liquors about and a 12v pc fan as the basis for my stirplate for building up yeastie starters, both are controlled by really cheap tattoo gun psu's from ebay, circa 10 usd complete with control knob and voltmeter.
u just need to short the footpedal jack and use a 1/4" mono jack to plug your 12v device in..

That is sweet! Basically a "dial-a-fan-speed" deal then?

Here is the cheapest one that I could find on Fleabay:
Tattoo Gun power supply unit

[PhatFil]

thats the thing, if u have a 12v dc power brick
http://www.ebay.com/itm/CPU-Cooling-Fan ... 2322536234" onclick="window.open(this.href);return false;" rel="nofollow

will give u the pot n nominal electronics to knock something up. but if u have to buy everything the tatoo gun psu is a tidy solution u can easily re-purpose to control any 12v dc device too.

[The KYChemist]

I've been doing a little research, on wiring up CPU fans for my controller box, the last couple of weeks. Most of the time, I get directed to a Mary Jane growing forum, but have found some decent info. It seems amperage, of the fans, plays a part as well. The fans I'm looking at draw about .160 amps. For this reason, I'm going to run two fans off a 12vdc .5 amp ac adaptor. From what I've read, as long as you don't go over the fans amperage by a whole lot, you should be fine. I'm also going to wire in a fan speed controller, as well.http://m.ebay.com/itm/281211781556?nav=SEARCH" onclick="window.open(this.href);return false;" rel="nofollow. This is what I have read... Will it actually work, only one way to find out. I had actually considered running them off a USB cable as well. I have a few extra cables, and might just see what happens, when my fans show up. The problem, I've read, with the USB though is that they only supply 5v. This would lead me to believe that the fans may just barely move. There are a few vids on YouTube, showing people that have done this, and there fans seem to spin fine. Looks like a little experimentation is in my future.

[PhatFil]

5v will run a 12v pc fan fine, just a bit slower, and your spot on with the amps ensure the dc psu is rated to supply more than your collective draw and it wont overheat.

[Soggy Bottom Boy]

...... The fans I'm looking at draw about .160 amps. For this reason, I'm going to run two fans off a 12vdc .5 amp ac adaptor. From what I've read, as long as you don't go over the fans amperage by a whole lot, you should be fine. ......

While that may be the case for battery charging (supplying too many amps for too long of a time, to a battery can cause heat damage, leakage, or exploding), I don't think it really applies to the amperage demand from motors. For motors, you want to make sure the supply has the capability to meet the demand of the amperage drawing capacity of the motor at maximum load. So, with a 12V, .5 amp supply, you could run no more than 3 of your .16 amp fans @ 12V(.48 amp draw), but running only 1 would be just fine too.

[Soggy Bottom Boy]

.

w00t !
Found the perfect wall wart in my collection of junk for my fan power supply. Now I can adjust the fan speed by supplying a stepped range of lower voltages.

It is a multi-voltage converter, so I can select 3.0, 4.5, 6.0, 7.5, 9.0, or 12.0 volts dc output. The fan might not start with the 3.0 and 4.5 v settings though, but I will soon find out. There is a polarity swap switch too, which is convenient.

I will probably get one of the tattoo gun psu's and build a stir plate too, just because.
.....a variable speed stir plate, how cool is that!.

[PhatFil]

.

I will probably get one of the tattoo gun psu's and build a stir plate too, just because.
.....a variable speed stir plate, how cool is that!.

u can use mine as a wot not to do template if u like,

a dead 2.5" hdd can be demolished for its disc platters one of which epoxied to a pc fan hub and centered will provide a lightweight magnet platform.. I used a heavy brass washer, whoops #1..

secondly get bigger magnets than i did mine are only 10mm x 3mm whoop #2

and last of all even with quick drying epoxy stick the magnets on one at a time , i didnt and they crept towards each other while the epoxy set whoops #3



u can see the tracks of glue WTF it took 5mins to knock up and works a treat.. tho the off set magnets do limit the speed as the bar wobbles and flys out of the magnetic field if span too fast.. stick the magnets on one at a time and u can avoid that too

[NineInchNails]

EDIT: I just realized you are using an AC fan. My post below is regarding a DC fan.

With the following parts you can control the rpm of the fan.
Rheostat - 3 watt, 25-Ohm (RadioShack part #271-265, $3.99) http://www.radioshack.com/product/index ... Id=2062299" onclick="window.open(this.href);return false;" rel="nofollow $4.29
Control Knob - most will work (RadioShack part #274-407, $1.99) http://www.radioshack.com/product/index ... Id=2102830" onclick="window.open(this.href);return false;" rel="nofollow $2.49
Flip Switch - most will work (RadioShack part #275-711, $2.99) http://www.radioshack.com/product/index ... Id=2062532" onclick="window.open(this.href);return false;" rel="nofollow $3.19

I made a stir plate using these parts and it works fine.