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fcukit88

PULLING MY HAIR OUT , How to wire these pc fans to mains?

26 posts in this topic

Hi There ok I am trying to construct a micro cab I bought everything I thought I needed :

4 x 80mm 4 pin molex pc fans (12v 0.25a)

4 x Y connector for fans

1 x HDD Power supply ( 12v 2a )

I plugged it all in and nothing , I thought this would work can anyone please tell me where im going wrong or point me to a way of powering these 4 fans from mains as the title said I am about to give up hope !

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Anytime I've ever used a pc fan I connect it to an old phone charger, works great. If you want to be able to adjust the speed you can get one of them multi wattage ones in the pound shop. Their just like a phone charger only they have a button to change the volts, from about 2.5 v up to around 12 I think.

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Tried one of those multi-voltage adapters myself and it had a stupid range of voltages :- 4.5, which wouldn't do it, and the next one up, can't remember exactly what, knackered the appliance. Can't remember what that was but it was definitely 5v, so make sure you get one which does exactly 5v or better still follow HailCannabis's advice and try a phone charger.

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cheers guys , will hooking one pc fan up to a old phone charger power all 4 of them ? is there a way to daisy chain them ?

and is there any tutorial videos on this?

Cheers for the help guys

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cheers guys , will hooking one pc fan up to a old phone charger power all 4 of them ? is there a way to daisy chain them ?

and is there any tutorial videos on this?

Cheers for the help guys

I've only ever hooked 2 fans to 1 charger, but it worked fine and I'm sure you could do 3 or 4. I just stripped the wires and connected them together then wrapped them in electrical tape. I don't think you'll find many tutorials for something so simple tbh. The low current won't shock you so just strip the ends from all the wires and experiment until it works. If you wire it backwards the fan will run backwards.

Eta, a pc fan has more than 2 wires, it's the black and red you'll be wanting. I just typed 'wiring pc fan to phone charger' into youtube and theirs a few videos on how to do it. All the best.

Edited by HailCannabis

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pound shop electronics are shite .

Really shite, i wouldn't want something from one in my growroom , no fucking way!

spend a few quid more and get one that does 12v ( 2-4amp should do depending on the total requirements of your 4 fans ), seeing as that's what the fans use.

the pc supply isn't working because it's not connected via a motherboard to a switch (as you'd have on the front of the case) so it might need 'hotwiring' but you'd need to google your psu type and method, unless someone fancies volunteering the info..

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I've only ever hooked 2 fans to 1 charger, but it worked fine and I'm sure you could do 3 or 4. I just stripped the wires and connected them together then wrapped them in electrical tape. I don't think you'll find many tutorials for something so simple tbh. The low current won't shock you so just strip the ends from all the wires and experiment until it works. If you wire it backwards the fan will run backwards.

Eta, a pc fan has more than 2 wires, it's the black and red you'll be wanting. I just typed 'wiring pc fan to phone charger' into youtube and theirs a few videos on how to do it. All the best.

There is 8 wires coming off of each of the fans 2 x 4 molex wires what do I do with the wires im not using ?

pound shop electronics are shite .

Really shite, i wouldn't want something from one in my growroom , no fucking way!

spend a few quid more and get one that does 12v ( 2-4amp should do depending on the total requirements of your 4 fans ), seeing as that's what the fans use.

the pc supply isn't working because it's not connected via a motherboard to a switch (as you'd have on the front of the case) so it might need 'hotwiring' but you'd need to google your psu type and method, unless someone fancies volunteering the info..

Hi its not actually a pc supply cable I believe it is a sata ac adapter the reason I bought it is because I wanted the safest option and I thought this would be it I am just puzzled as to why it is not working here are pics of the HDD Power supply with amp and volt ratings

gallery_60441_4140_28228.jpg

gallery_60441_4140_22367.jpg

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Looks fine, i've one the same / similar (have you checked the fuse ?)

i'd replace the cable for another pc mains lead if you have a spare.

i've found them to be loose on psu's like that , occasionally making a crackling noise when it wiggles :fear: ( some even without a fuse , just a small moulded '13A' plug on :headpain: )

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There is 8 wires coming off of each of the fans 2 x 4 molex wires what do I do with the wires im not using ?

Hi its not actually a pc supply cable I believe it is a sata ac adapter the reason I bought it is because I wanted the safest option and I thought this would be it I am just puzzled as to why it is not working here are pics of the HDD Power supply with amp and volt ratings

gallery_60441_4140_28228.jpg

gallery_60441_4140_22367.jpg

You've got it wired in the 5v output, some fans will run slow from 5V, some won't run at all.

Put the black wire from all the fans into the middle socket, and all the red wires in the 12V socket(there is an empty socket between 0V and 12V).

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Looks fine, i've one the same / similar (have you checked the fuse ?)

i'd replace the cable for another pc mains lead if you have a spare.

i've found them to be loose on psu's like that , occasionally making a crackling noise when it wiggles :fear: ( some even without a fuse , just a small moulded '13A' plug on :headpain: )

Hi there when I plug the pc cable into the unit it lights up a little led so power is getting to it its just not powering the fans?

You've got it wired in the 5v output, some fans will run slow from 5V, some won't run at all.

Put the black wire from all the fans into the middle socket, and all the red wires in the 12V socket(there is an empty socket between 0V and 12V).

sorry I dont have it wired to anything I haven't striped any wires from anything I just plugged the female connection of the power supply directly into the fans 4 pin male connection ?

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I reckon the empty socket is the cause of the problem then, as the 'Y' connectors have four wires each, one red (5V), one yellow (12V) and two black (0V). The two black wires are normally connected together inside the PC PSU, but that PSU only has one connection for 0V. The fan and 'Y' connectors are wired : red, black, black, yellow.

Basically you need to connect the black wires together.

If you like I can draw you a simple diagram to explain it better!

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I reckon the empty socket is the cause of the problem then, as the 'Y' connectors have four wires each, one red (5V), one yellow (12V) and two black (0V). The two black wires are normally connected together inside the PC PSU, but that PSU only has one connection for 0V. The fan and 'Y' connectors are wired : red, black, black, yellow.

Basically you need to connect the black wires together.

If you like I can draw you a simple diagram to explain it better!

when you say empty socket do you mean the black hole on the ac adapter on the pick I showed ?

I would absolutely love a diagram I have no idea whats going on with this being trying to do it for ages and hit a brick wall , plus im smoking "the widdow" which cant be helping.

this is how each of my fans is wired bellow the came like this when I ordered

gallery_60441_4140_4949.jpg

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gallery_46350_5285_32768.jpg

Basically all you need to do is connect the two 0V wires (black) together to complete the circuit.

e2a Sorry about the delay getting back to you, I couldn't find my scanner lead!

Edited by NattyFido2
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Man thanks for the help couldn't have asked for more , do have one more question though haha

When you say connect the black wires you mean the black wires on the fan it's self and the psu unit remains intact ?

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That's how I would do it, just strip a bit of insulation from both black wires on the fan and twist them together, then cover with insulating tape. You only need to do it to one fan or one 'Y' cable.

Normally, inside a PSU all the black wires are connected, the maker of that particular PSU has tried to save a bit of money (10p?) by only having one 0V socket!

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