Tutorial: Change the colour of a LED fan.

In this tutorial I will be modifying a Blue LED Xilence 120mm fan into a Orange LED Xilence 120mm fan.



I used:-

4x Orange Super Bright 5mm LEDs (worth about 40p)
Soldering iron and thin solder (nicked from work)
Some scrap wire (from a telephone extension cable)
A point thing on my penknife.
12v power source (nicked from work)


On this image you can see that the LEDs have one long leg (Anode +ve) and one shorter leg (Cathode -ve). You can also see that the Anode has a smaller metal element inside the LED body.


On my fan the LEDs sat inside a 5mm hole and simply required a bit of force on the rounded lens side of the LED and they just popped out. So I did this with all 4.


Here's an extracted LED


The wiring of my fan, like my other LED fan consists of 4 spokes of wiring coming out of the hub of the fan. Each spoke is supplied by a single resistor stepping down from the 12v source at the centre. The resistors in my fan are 510 ohm which is fine for any colour LED.


I could also see which wire was +ve because Xilence had thoughtfully marked it on all spokes for me. I also coloured in the +ve wire with a red marker just to make it easier for me to identify.

So now to trimming off the existing LEDs. Just snip them off and discard, keep as appropriate. I made a bit of a mistake and trimmed all LEDs back, forgetting that the wires would be too short. In hindsight I would probably just stick the full size LED in the hole and solder the wires to it directly, trimming down afterwards.

Next step is to bare a few mm of wire from the +ve and -ve wires (no pic)

So now onto soldering. Preparation is pretty important. It's a good idea here to pre-tin the bare wire and LED leg.


Heat the bare wire/LED leg a little with the iron and allow some solder to melt onto the subject. This cleans and removes impurities from the surface and allows a much stronger and electrically sound joint to be produced.

Soldering the LED to the wire.
Holding the LED with something introduce the tinned wire to the leg of the LED and introduce some heat with the iron, and feed a little solder into the joint as it warms up. Remove heat and hold until the solder solidifies. Plenty of tutorials in soldering available on youtube if you are unsure.


And soldering the other leg.


Do the same for all four and you should be good to test. Wire up the fan to a 12v source, such as a power brick like mine or any 9v to 12v power brick.


Pop the LEDs into the fan.


And revel in it's glory.


Night shots:






Additional notes.

There are different ways that manufacturers make their LED fans.

Here is an image of the hub of one of my other LED fans (A Coolermaster red LED fan)

This one uses traditional stripey resistors, in this case 470 ohm so will be a shade brighter than my 510 one on same LEDs. The higher the resistance the less the power that gets to the LED.

If your fan uses significantly lower resistance than 400 ohms when switching from blue/white to red/orange then you may need to install an additional resistor to bump it up a little.


Guide: Make something like this out of a standard fan. Click the image below.


I appreciate your feedback and will add to this guide as new information arises.


#First draft 07/08/2010.

Which resistor to use in your circuit?

Here's a website where you can enter the values of your chosen LED and it'll tell you which resistor you need.
http://led.linear1.org/1led.wiz

And one where you can build arrays of LEDs for more complex projects.
http://led.linear1.org/led.wiz

Not a defacto standard but somewhere to start.

Thanks to Akempster for giving me the idea to include it.


Common discrete LEDs come in 3 basic sizes

3mm, 5mm, 10mm.

This is the diameter of the dome shape but other dimensions such as height are also affected.

Excellent guide mate, very clear.

It's a question that gets asked a lot, so this is a great point of reference.

Very nice

Should probably add how to remove the blades from the body.

Good going. I meant to do this months and months ago. Even bought a couple of LED fans but never got round to doing it!

Thanks PhillyDee but it isn't necessay to remove the blades from the fan for the purpose of this mod. I just fancied destroying the Coolermaster one (worst silent fan ever) and as I had it in bits thought I'd chuck it in there for illustration purposes.

Great thread, very useful indeed. Stickied.

Quality thread

Very good advice

But, if every individual tutorial is stickied, surely eventually half the first page will be filled just with stickied tutorial?

Good tut and jesus that "thing" looks emense

Well done Tealc, looks like this is the first Tutorial to get stickied

Is it possible to get LEDs of different brightness? Just white ones?

Yes Muel.

The brightness index for LEDs is the millicandela (mcd). Indicator LEDs can be 50 mcd while superbrights can reach up to 15,000 mcd. I tend to buy the brightest I can find, but sometimes the sellers get a littler carried away and exaggerate their brightness. There are also many different white colour LEDs, from soft to more hard white.

The other way to decrease or increase brightness is to change the voltage and resistance in your circuit. A circuit with a 400 ohm resistor will provide a brighter light than one with 500 ohm. A LED running at the top end of it's current range will be brighter than one at the lower end of it's current range.

Well my idea, (which will probably never happen), is to have a button on the front of my case which will turn on/off all the the LEDs in all of the fans, and also ramp the fans up to full speed.

I'm guessing then that I could have 3 variable resistors in there somewhere as well, one for the speed of normal use, one for the speed of load use, and one for the brightness of the LEDs.

Yes but you could also use standard Diodes to drop the voltages as Diodes have a pretty universal voltage drop across them. I seem to recall that it's about 0.7v per Diode. Variable resistors or potentiometers are tricky because each fan will respond differently to the drop in voltage and current.

I need to do more research on this phenomenon.

It does sound like it's going to be a big project, but we'll see.

Would they need connecting in series then not parralel? Because if I'm going to be running 4 fans, all with 12/16 LEDs, if I connecting them in series, wouldn't the last one be less bright than the first one?

LEDs wired in series doesn't work like that. They will all be as bright as each other, but you can only wire so many in series.

If you are using white LED then you are limited to about 3 per LEDs leg at 12v becauee when wired in series the LED voltages are added together. You could wire one resistor per LED but that just get's messy.

Here's the best way to wire LEDs, this method uses less power and is neater.



You can do multiple mini circuits like this. Each series of 3 LEDs gets it's own 12v source, stepped down a little by the resistor. This is how I wired up my black case fan with the orange LEDs, although I used a 150 ohm resistor for because they are Orange LEDs.



As you can see this is pretty useful for 3 LEDs per side of the fan as you can hide away the resistor in one of the corners.

Thanks for your help dude! Looks like all I will need to do then is provide two 12v power sources to each fan, one for the fan motor and one for the LEDs?

Also, could I in theory connect both +12v lines to a single negative?

Yes, you can connect them to the same ground. In this case it would not matter, but in others you would make sure that the ground is capable of carrying both loads and would probably result in a thicker cable. Althoug hin this case, it doesn't matter.

LEDs on eBay are the really poor type known as XLeds. They are meant for throwaway toys. All LEDs have a burning in time where they lose their initial brightness. The cheaper the LED the quicker the burn time, the less life you get.

Cheers for all the info, it'll come in useful! I have a fair bit of soldering and wiring experience from owning old motorbikes, but as for component selection I tend to struggle a bit.

I'll probably never do the mod though, it takes so much time and money, and I don't have a lot of either. Also it seems a bit counter-productive to mod an Antec 300 more than mine already is...

i would just like to make one area clear to add to the excellent guide so far.

each LED will have its own voltage rating et.c to be used at. If you google "LED resistance calculator" you will find some sites that allow you to type in the voltage used by each LED that you would like to use as well as how much in each series (line) you would like to use. They will calculate the appropriate resistor that you need.

by choosing a more accurate resistor you can not only keep the LED as bright as possible but also make sure it isn't going to get to much voltage and reduce the LED's lifespan. hope this helps anyone who is also looking to do this kind of mod.