[PLUG-TALK] Another use for 12 volt fans?

Tomas Kuchta tomas.kuchta.lists at gmail.com
Fri Sep 22 00:06:59 UTC 2017


Relying on this kind of active solution for safety inside a wall build to
outlast you seems like - what could possibly go wrong!

I suggest looking for passive systems such as radiation, separation,
chimney effect, heat resistant materials, etc. Or getting less heat of your
fireplace.

In case you persist, USB power source or wall wart is more than enough to
supply less than 0.5A for these fans. Maybe, you do not even want them
spinning at max speeds/voltage/current.

Unless of course, the solution is not meant to outlast you! Take that as
you will....

Tomas

On Sep 21, 2017 4:15 PM, "Keith Lofstrom" <keithl at kl-ic.com> wrote:

> On Wed, Sep 20, 2017 at 10:08:40PM -0700, John Jason Jordan wrote:
> > 1) I asked my friend Mr. Google about sound levels for computer fans
> > and came up with Noctua as offering the quietest fans. Does anyone have
> > experience with the Noctua fans or alternatives?
>
> I've used Noctua fans, they are indeed very quiet ... and
> much more spendy than the cheap Asian fans.  Worth it.
>
> > 2) What about power supplies? I don't need a lot of current for my
> > plans. Are there very small power supplies (preferably without fans)
> > that would provide enough current for half a dozen four inch fans?
>
> I use these power supplies for deploying LED strip lights.
> At full load (hot), they don't last as long as half load.
>
> If 3 or 5 amps will do it, I have a couple of cheap Asian
> power supplies (via Amazon) that will work.  The problem
> with these is that they are decently designed but poorly
> assembled; before you install one, I want to disassemble
> it and correct soldering mistakes so it doesn't fail
> when hot.
>
> If the fans stop, will that cause BAD THINGS to happen
> with the setup you plan?
>
> BTW, you want to push room air INTO the fire with the
> computer fans, not pull heat off it.  Plastic fans and
> precision bearings won't survive long when hot.  These
> fans typically blow room air INTO a computer (especially
> through the power supply), not suck hot air out.  You can
> use one of the fans to push heat past the little 12V power
> supply and into the fire.  USE the heat the power supply
> makes, and keep it cooler so it lasts longer.
>
> The power grid is overloaded and flaky; consider a battery
> to keep the fans and fire going when the power goes out.
>
> Lastly, big slow fans are much quieter than small fast
> fans for the same amount of air flow.  IIRC, double radius
> at 1/4 the RPM moves the same air with 1/16 of the noise.
>
> Keith
>
> --
> Keith Lofstrom          keithl at keithl.com
> _______________________________________________
> PLUG-talk mailing list
> PLUG-talk at lists.pdxlinux.org
> http://lists.pdxlinux.org/mailman/listinfo/plug-talk
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.pdxlinux.org/pipermail/plug-talk/attachments/20170921/f42681c0/attachment.html>


More information about the PLUG-talk mailing list