Fanbus suggestions

llatsni

See attached image.

This is my custom design for a fanbus, basically it takes its power from one regular molex extension from the PSU and then sticks it through 5 switches that switch the power between 12V and 7V, i.e full power and stealth mode. While still leaving the fan monitor leads plugged into the motherboard.
Those are tri-coloured leds, and 470ohm resistors, and on-off-on toggle switches.

My questions are:

1. will it work?
2. how could it be better? (I dont want to use rheostats)
3. is there too much draw from 5 fans on one 12V/5V line?
4. i.e is there a danger of blowing the whole lot say if I switched all the switches rapidy in succession? a la a little kid?

Please some feedback...

JustHalf

Originally posted by llatsni
4. i.e is there a danger of blowing the whole lot say if I switched all the switches rapidy in succession? a la a little kid?

Why do I have the feeling that even if you were told not to do this you'd do it anyway?

Don't know much about fanbus's though (just in case you were wondering why I wasn't posting anything relevant).

po0k

I've something brewing here at home.
Not quite perfected yet.
Thinking of getting a FAN bus for the new PC. The home Br3w is just for an old PC and a bit of a laugh.

I've a diagram of it around somewhere.
Does a simple Voltage divider trick.
uses a switch to go from 12V to 9V to 6V
At the moment I don't have enough current to push the fan (80mm, 12V, 0.15Amps). Could be the power supply I'm using (one off a Ethernet Hub) or the resistors themselves (big chunky ones for about 10Watts).
Have yet to hook it up to a proper PC PSU. Will do soon.

Boston

what is it with people wanting to make their own fanbus's i just dont understand why you would go to that tiem and hassel when you can buy perfectly decent ones over the net

po0k

Because You don't have to buy them over the net, or at all in fact.
And what hassle?
Once you start fecking about with stuff you learn how they work and (sometimes) how to improve em

Boston

i know how they work, i guess id rather spend my time doing something a little less partical and a little more mondane

Gerry

1. No, well maybe it does but I don't see which wire is connected to which in the 5 blocks at the top. I can't even see the switches...

2. Use rheostats. Much simpler, and much finer control. So what if they put off a little bit of heat, mount them on a metal plate, and much of that tiny amount of heat will dissipate to the outside.

3. No

4. No

Gerry

Originally posted by Boston
what is it with people wanting to make their own fanbus's i just dont understand why you would go to that tiem and hassel when you can buy perfectly decent ones over the net

Oh, I must have missed this startling insight earlier. Why do people make anything themselves? Right boston, theres 2 main reasons. The first one is they want to make it themselves, they actually enjoy doing it. Its actually quite nice to be able to say "yeah, I made that". The second reason is that you may save money.

The rheostats to control my fans cost me literally a couple of quid. I should be able to make a decent control panel for them out of old spare parts for precisely €0.00.

If you don't have anything worthwhile to contribute, don't bother posting.

Boston

ill not insult you as ill most likely need your help in a weeks time.

So what your saying is its a hobby?

Gerry

Well, it could be a hobby, if you spend a lot of time messing around with computers/electronics. Some people just do a few mods, and then leave it. I usually wash the car myself instead of bringing it to the car wash, but I don't consider it a hobby.

Inspector Gadget

I've seen a number of people attempting this sort of thing (a so-called "rheobus") on a UK forum site, and the most common thing that went wrong is that they underspecified their rheostats/variable resistors/potentiometers/whatever-you-want-to-call-thems, and they burnt out :rolleyes:

To drive the bigger stuff (like the 80mm Delta "Screamers" or the faster 120mm jobbies) you'd want something that can handle 10W continous as a minimum.

Gadget

Gerry

My 120mm fan is 3.5 watts, and on 12volts it can be heard all over the house, so I run it on 6 volts. I'm not sure I want to hear a 10watt 120mm fan running at full speed

Inspector Gadget

Yeah, but some fans are thirstier than others. One cheap example is the higher end 120mmx38mm YS-Techs (FD1238's), that draw 10.2 watts. :eek:

Also you don't want to be pushing the resistors close to their limits as they'll fail sooner due to thermal problems (or even arcing, depending on how much current we're actually talking about)

Just a thought... perhaps I am overdoing it a little, but having heard of people burning out Maplin's 3.5W examples with fans rated lower than that number, I'm suspicious of them...
Gadget

Gerry

I dunno, I got mine out of maplin about a year ago and they are still good. 3.5 watts through one, and 4.4 through the other. You mention the ys-tech, I wouldn't mind getting a decent quality 120mm fan, instead of the usual generic crap. The ultimate fans I reckon are the high end panaflo's, nice and quiet but moving loads of air.

Boston

ive four of those 120mmx38mm YS-Techs, which i use a 12volt fanbus on, and it works grand

PPC

I've got 1x YSTech FD1238 120mm fan

Specifications :
» Speed - 2800RPM
» Output - 125CFM
» Decibels - 40.5dBA
» Dimensions - 120x120x38

and 3x Delta 80mm
Specifications :
» Speed - 4900RPM
» Output - 68.51CFM
» Decibels - 48.5dBA
» Dimensions - 80x80x38

2 x Coolermaster (delta) DP5-6I31C
Dimensions 60 X 60 X 13 mm
Rated Voltage 12 VDC
Rated Speed 5400 R.P.M.
Air Flow 27.72 CFM
Noise Level 38 dB(A)

1x Thermal Take Crystal ORB
SPECIFICATION
Fan Dimension 50x50x15 mm
Rated Voltage 12V
Rated Current 0.16A(max.)
Power Input 1.92W
FAN Speed 5500±10% R.P.M
Air Pressure 4.1mm–H2O
Max. Air Flow 12.4CFM
Noise 26.4dBa

1x RAM fan.

I've taken out the rest for the mo till i get more room in my pc

____
Annoying Signature

Inspector Gadget

Originally posted by Gerry
I dunno, I got mine out of maplin about a year ago and they are still good. 3.5 watts through one, and 4.4 through the other. You mention the ys-tech, I wouldn't mind getting a decent quality 120mm fan, instead of the usual generic crap. The ultimate fans I reckon are the high end panaflo's, nice and quiet but moving loads of air.

The Panaflo H1A's (high performance) are good, no question; another worthy make of fans is EBM/Papst; they fit counterweights opposite each fan blade to minimise vibration...

Gadget
P.S.> Did you know that RS stock Panaflos? Their own-brand "Hydro wave bearing" fans are actually Panaflos, for what it's worth... at least it means there's a source in Ireland for 'em...

Gerry

yeah I'll probably try a H1A and an L1A and see what the performance/noise ratios are like. Pretty sweet that RS stock em ok.

JustHalf

RS? What are RS? Radio Shack? If so, I didn't know there was one in this country.

By the way PPC, you should try to think more about efficient cooling, as opposed to excessively loud cooling (which is what you've got).

PPC

forgot i got a delta 92mm blowhole.
It is efficent.
I max at 39*c now

JustHalf

Congratulations. I max out at the same with a 33% overclock (1GHz to 1333MHz) and far less fans (and less noise too, probably, and that's saying a lot considering how loud my box is).

astrofool

I think JustHalf is jealous

Inspector Gadget

Originally posted by JustHalf
RS? What are RS? Radio Shack? If so, I didn't know there was one in this country.

By the way PPC, you should try to think more about efficient cooling, as opposed to excessively loud cooling (which is what you've got).

RS are a multinational company (I think the group's called ElectroComponents) that sell, well, everything an electrician/electronic engineer/etc. etc. would ever need (from solder to screwdrivers to multimeters, to ICs to enclosures, to work clothing to... need I go on?). Their Irish presence is in Dublin; drop in on www.radionics.ie if you want to have a gander at the huge range of stuff they stock. It's not the cheapest by any stretch of the imagination, but nine times out of ten it's on a shelf ready to ship when you place the order - that's the thing that makes them great, in my opinion...

Gadget

JustHalf

Originally posted by astrofool
I think JustHalf is jealous

Yeah, I'm jealous of the pain I could be having inside my head right now.

PPC

Originally posted by JustHalf
Congratulations. I max out at the same with a 33% overclock (1GHz to 1333MHz) and far less fans (and less noise too, probably, and that's saying a lot considering how loud my box is).

You running at 1.9v aswell?
It drastically increases the temps.
I used to max at 29*c but i increased the voltage and temps went mad.

JustHalf

No, I'm running it at 1.775 volts, because there's no need to run it any higher.

If you have to up your voltage that much to get it stable, it could be a weird-ass powersupply/motherboard. If you can check your voltages at run-time, do. They might be fluctuating at high power draw.

If you've 7v modded your fans (as you've claimed before) you're going to be running a lot off the 5v line. Try putting them on the 12v line, and seeing if you can lower your core voltage.

I *think* the processor draws power from the 5v line. Even if it doesn't, when using both the 3.3v and 5v line (which you are) you only get half the wattage.

PPC

I changed the voltage on the chip to get it more stable and its rock solid since i've put a fresh copy of XP Pro on and upped the voltage.
Once i get a new mobo i should be overclocking more so i'll drop the voltage back on the chip

Gerry

running a fan on 7v uses the 5v line as a ground, so it isn't actually drawing power from it.

PPC, if yer overclocking more, how do you think you will be able to drop the voltage?

llatsni

Weell, I made it.

Took me flippin ages to solder all those wires onto those tiny contacts. All the LEDs work correctly, which is cool, I'm gonna test the voltages tonight.

It cost me WAY more than I expected. Like about E30. DOH!!, but I really wanted to make it myself, and none of the ones you can buy have 5 controllers on them, so I would have needed to modify a ready made one which kinda defeats the point.
I did it quite professionally actually. I heat-shrinked all the connectors and exposed wires!

I havnt tried it with my new fans yet (all low-panaflos) but as soon as its test rigged up, I'll post a few photos. I wasnt arsed to take them as I did it as it was painfully frustrating building it.

Gerry

you better be going to the lan this weekend you spanner !

po0k

played Ilianti.
I've gotten my simple-thing to the bread-board stage but progress is slow due to lack of time and parts.
Not getting enough current out at the moment (using the power supply from a 24-port hub I'm 'fixing' as a 16-port (one chip blew)).
have a 200Watt AT PSU lying aboout that I could use, just can't be arsed doing anything at the moment.
Can't start painting till the weather gets warmer too.
Being about 200miles from Peats/Maplins kinda hurts too