Where to buy 3.3V 40mm fans?

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Forums › LAN (ethernet/Wifi/routers/Bluetooth) › Where to buy 3.3V 40mm fans?

Skolink

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Topic # 108866 7-Sep-2012 10:31
Hi, Does anyone know where I can buy a 3.3V d.c. 40mm x 40mm fan? The fan in my network switch has died. I have looked on Ebay, Element14, RS, local computer stores, Google. The only source I can find is DHgate, minimum qty 100 pcs. 5V and 12V are prolific of course. The switch internal PSU has only 3.3V output. I found replacement 40mm fans for specific Cisco etc switches, but there is no mention of operating voltage. I have tried 5V fans, but they turn so slowly that virtually no air is shifted. The switch gets too hot with no fans. The only other option I can think of is to buy/assemble a 3.3V to 5V dc-dc converter. Cheers,

timmmay

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Reply # 682712 7-Sep-2012 10:39
Can you not buy the replacement part from your switch vendor? What make/model is the switch? Asus eee pad transformer iPod 2G Windows 7 PC Lots and lots of Nikon camera gear

RunningMan

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Reply # 682722 7-Sep-2012 11:05
Is there a 5v power rail in your switch?

Skolink

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Reply # 682776 7-Sep-2012 12:28
timmmay: Can you not buy the replacement part from your switch vendor? What make/model is the switch? Its a budget brand like CNet or something more obscure so I had assumed not. I won't be home until Sunday so I can't provide that information until then. I guess it could still be possible.

Skolink

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Reply # 682778 7-Sep-2012 12:31
RunningMan: Is there a 5v power rail in your switch? No, only 3.3V, and 330V dc. I think the regulation is done on the switch PCB, to an even lower voltage. I will check though, because if there are linear regulators on the power supply, there must be a ~4V rail.

Skolink

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Reply # 684117 10-Sep-2012 21:34
There isn't any other d.c. rail on the power supply, just the unregulated "3.3V" rail that is then regulated on the logic PCB. The switch is an Edimax ES-3132R

ubergeeknz

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Orcon

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Reply # 684121 10-Sep-2012 21:38
Have you tried taking the label or plug out of the back of the fan (where the bearing is) and adding a drop of 4-in-1 oil? This will often get another few years out of a sleeve bearing fan, they usually only fail because the bearing has dried out and re-lubing the sucker is all it takes. Might save you an expensive exercise! Otherwise check polulu, sparkfun or mindkits for 3.3v -> 5v step-up converters... Edit: oh and not WD-40 or CRC 5-56 - these will get you going for a while but will dry out after a few months.

Skolink

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Reply # 684160 10-Sep-2012 22:38
ubergeeknz: Have you tried taking the label or plug out of the back of the fan (where the bearing is) and adding a drop of 4-in-1 oil? This will often get another few years out of a sleeve bearing fan, they usually only fail because the bearing has dried out and re-lubing the sucker is all it takes. Might save you an expensive exercise! Otherwise check polulu, sparkfun or mindkits for 3.3v -> 5v step-up converters... Edit: oh and not WD-40 or CRC 5-56 - these will get you going for a while but will dry out after a few months. Thanks, yes. When I got the switch (2nd hand) the fan was a bit noisy, so I peeled off the label and put in some molybdenum grease. The fan was fairly well seized and hard to turn when I took it out. Perhaps I could have re-lubricated it, but I didn't think of that before I threw it out. Thanks for the suggestion of polulu etc, I'd never heard of them. I nearly ordered a step-up converter for only US$5.45, but then when I saw the postage price it occurred to me to check Ebay, since Chinese / Hong Kong postage is often only $1. Sure enough I bought 2 units for 99c each plus $1 postage. I guess I'll get them in a couple of weeks.

Skolink

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Reply # 689879 22-Sep-2012 14:36
The voltage boosters arrived, and I installed one inline with the fan. Now it is whining away like a real switch. Initially it was rattling horribly so I peeled back the label and put some molybdenum grease in the bearing.