Homemade fan controller wiring Q???

[Darth Joules]

'm the process of modding my PC and I need some help...

I plan to build a homemade fan controller for my CPU fan, 3 case fans
and a cold cathode tube. I need to find somewhere in the UK that
sells a single rheostat dial (usually on a PCI backplate). This will
be dismantled and then (re)mounted into a 5.25" bezel for a front bay.
Anybody know where I can get a good one?

Also I will mount 4 toggle switches (from Maplin) into the bezel. 3
to turn the power on and off to 3 case fans. And the last switch for
the cold cathode tube. Now here's the question....

The 3 case fans I wish to turn on and off will also be conected to an
Akasa Fan Controller. So the red and black power cables will first go
into the toggle switches and then out to the fans themselves. Thus
allowing me to switch them on and off, even when the PC's on. The
speed cable (usually blue) will bypass the toggle switches altogether.
Is this a sound idea? And will it work? If so, what sort of toggle
switch (voltage/tolerance specs, etc should I get or doesn't really
matter?


Cheers,

Darth Joules

 

[kony]

'm the process of modding my PC and I need some help...

I plan to build a homemade fan controller for my CPU fan, 3 case fans
and a cold cathode tube. I need to find somewhere in the UK that
sells a single rheostat dial (usually on a PCI backplate). This will
be dismantled and then (re)mounted into a 5.25" bezel for a front bay.
Anybody know where I can get a good one?

One rheostat? You plan to control the speed of all 3 fans with one?
"Most" rheostats are low-wattage, it would be better to buy a pre-made
kit than could support up to 20W per channel.

Also I will mount 4 toggle switches (from Maplin) into the bezel. 3
to turn the power on and off to 3 case fans. And the last switch for
the cold cathode tube. Now here's the question....

Many of these pre-mad kits have integrated switch too.

The 3 case fans I wish to turn on and off will also be conected to an
Akasa Fan Controller.

Then what's the point of the rheostat, to find-tune it? "Fine-tune"
may be the wrong concept, since that would seem to mean individual
control over each fan, since even at same RPM they'll have different
functions and associated noise levels.

So the red and black power cables will first go
into the toggle switches and then out to the fans themselves. Thus
allowing me to switch them on and off, even when the PC's on.

I assume the Akasa Fan Controller is a thermally-adjusted controller?
If so, why would you ever want to turn them off? A fan running at
minimal RPM is silent... not subjectively silent, but actually cannot
be heard outside of the closed system. Of course this depends on the
fan too, but in general this applies to the typical 40 to 92 mm "PC"
fans. Some of the larger >+120mm fans have their own internal voltage
regulation so they don't take well to external controllers at all.
Such fans can be disassembled and modded but it's just a big hassle to
do instead of buying a different fan.

The
speed cable (usually blue) will bypass the toggle switches altogether.
Is this a sound idea? And will it work?

Yes, it can bypass the switch. The ground wire can also bypass the
switch.

If so, what sort of toggle
switch (voltage/tolerance specs, etc should I get or doesn't really
matter?

Anything large enough to be manipulated by (human) hands will have a
far larger rating than needed for a fan. Buy the switches you find
attractive and sturdy, keeping in mind that a really tiny &
inexpensive switch is more subject to failure, but then again you
probalby won't be flipping that switch very ofte

 

[Vanguard]

Sounds like a lot of work just to save $40 (USD). While I can do the
mechanics, too, labeling is my sore point. I'm no good at making
professional quality labels. Have you looked at Vantec's Nexus fan &
light controllers (www.vantecusa.com)? List price for their NXP-301 is
$39.99 (USD). They do list sales outlets in the UK
(http://www.vantecusa.com/wheretobuy.html#uk) or maybe a Google search
will show vendors in your area. But then maybe you want home-made
looking custom mods.

 

[Darth Joules]

One rheostat? You plan to control the speed of all 3 fans with one?
"Most" rheostats are low-wattage, it would be better to buy a pre-made
kit than could support up to 20W per channel.

No, only the CPU fan will be controlled by the rheostat dial. Which
WILL BE a pre-made single rheostat kit only dismantled and added to
the bezel mod.

Many of these pre-mad kits have integrated switch too.

I've seen the Zalman fan controller which does this. Good piece of
kit, but doesn't meet my requirements.

Then what's the point of the rheostat, to find-tune it? "Fine-tune"
may be the wrong concept, since that would seem to mean individual
control over each fan, since even at same RPM they'll have different
functions and associated noise levels.

I could in essence just use the Akasa Fan Controller to wind down the
RPM of four fans till they're near silent. But they're still using
power, so being able to switch three of the four off will conserve
some energy. And it gives me something to fiddle with, and something
to make. Perhaps the missing piece in the whole equation is the mobo
I will be using, which will be the Gigabyte 7VN400 Pro. With its
DUAL-BIOS I can run the PC either overclocked or at its normal clock
rate. When running on the normal (default) BIOS I won't need so much
cooling, hence the fun idea of pissing around with very defined fan
control. It is also an experiment towards a future mod.

Also, all the fans are the same make, model and size. So there is no
different functions and associated noise levels.

I assume the Akasa Fan Controller is a thermally-adjusted controller?
If so, why would you ever want to turn them off? A fan running at
minimal RPM is silent... not subjectively silent, but actually cannot
be heard outside of the closed system. Of course this depends on the
fan too, but in general this applies to the typical 40 to 92 mm "PC"
fans. Some of the larger >+120mm fans have their own internal voltage
regulation so they don't take well to external controllers at all.
Such fans can be disassembled and modded but it's just a big hassle to
do instead of buying a different fan.

The Akasa Fan Controller is not thermally adjusted. It has four
rheostat dials and LCD display for speeds and four temperature
sensors. Having all that in one package is why I am getting it.