I'm making something similar to
- one 12v fan in a box. It worked well from a 12v wall wart for about 2-5 minutes then stopped, though the lights (lighted fan) blinked about once per second. There was a hot component, so I let it cool. When I turned it back on it burned up. As far as I can tell the component was labelled "b62871"- my best guess is it is
one of these. It is part of a voltage step-up convertor from
here. However, the banggood page says input voltage from 2-24v, and output from 5-28v. On that component pdf, it says input voltage is 11v max. And yes, I have 4 more of them to try out.
Eventually I plan to run it from an 18650 battery (~3.7v) to my desired fan voltage (12-15v), but atm I'm running it from a 12v wall wart (12.3v measured), to 16v out (to allow for any dropout voltage issues), which should be well under the 2amp rated for the boost converter. I thought the heat and other issues would be minimized doing this.
I did accidentally hook it up backwards at first.
The wall wart may or may not be regulated, though I have the components (lm317 and so on) to regulate it before the boost convertor if you guys think that may help. Could it be that the product page is wrong and the input voltage is out of range? Could it be a current issue? Thermal issue? I don't think a single fan would draw too much current, probably only 1 amp max, which is half the rated current.
edit: sorry, I screwed up the html so half my post was hidden :p