Looking for super quiet low air flow muffin fans. small is ideal. 5~10cm ideally. I was in a computer repair shop asking, and they had lots but the airflow was pretty high. I am looking for something to use in confined small animal enclosures so dont need the draft, just some air circulation that is super quiet. The pet shops I have been to were also a bit too high a speed (for aquariums).
Any suggestions on the types of stores I could try asking would be appreciated I could buy overseas ,but I prefer buying within Taiwan if these are a thing here.
Get a computer fan rated for certain volts (say 12) and run them at a lower voltage and they will spin slower. Better to get a larger fan that turns slow to get the most airflow with the least amount of noise.
Is that safe? I am vastly ignorant of the inner workings of these fans.
I use computer fans now, but the noise is an issue, particularly at night. low air flow is the goal, which seems the opposite of the cooling a computer may require.
Fans will also have a low-end startup voltage. Some 12v fans may stall at 5v and only start to rotate at 7v. You could also consider getting (or making) a PWM controller with a PWM fan. PWM fans usually have a large RPM range like 300-1800rpm. Then run it at 300rpm.
As suggested above, just use a lower voltage to operate it - Iâve done this on occasion and never found any problem with startup. I have a bunch of aluminium Sanyo Denki (San Ace) fans sitting around somewhere - I can root them out if youâre interested. Theyâre old stock but high quality. This sort of thing:
PWM fans have a fourth wire on the connector (the other three are for power and RPM sense) which accepts a PWM control signal. So no, youâd need a controller, and tbh Iâve never seen such a thing off-the-shelf. These fans are designed for PC motherboards.
IMO this is overkill. A fan has very low mechanical friction and therefore doesnât need much starting torque. You should be able to operate one at (say) half its rated voltage with no problems at all.
You donât need a PWM controller. A small variable voltage DC supply is enough. Or actually you can just put a pot between the supply and the fan to vary the voltage.
An easy way to run a 12V DC fan at a lower voltage is to buy a âusb to fanâ wire from Shopee or Guang Hua. USB runs at 5V so your fan will run slowly. You can run the USB end into a USB wall adapter.
I do this for some extra cooling on routers and switches. I put the fan on top of the device and plug the USB end directly into the back.