Possible to run random cheap fans slowly enough to be quiet?

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THX1138
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Joined: Wed Jul 12, 2017 12:33 pm

Possible to run random cheap fans slowly enough to be quiet?

Post by THX1138 » Wed Jul 12, 2017 12:46 pm

I'm making a couple of spotlights for video recording (just a hobby) using CCFLs out of a lot of broken monitors that I got for free. My problem is that I will have so many in such a small space that I think forced convection will be necessary. I was wondering whether I could use cheap fans salvaged from dead PCs at the same place I got the monitors (a community repair workshop) and run them slow enough that they won't affect the video recording. I read somewhere that the slowest I can run a 12 V fan without stalling it is 3 V (and it might need as much as 6 V for start up). Is 3 V low enough to make a crap fan quiet? Can many run lower than 3 V? Thanks.

I made this video to show how I think the fans could work (and also my original idea which I thought could be passively cooled but without a way to easily fix the CCFL tube to the plate (because of the bulky insulation at each end), I think it won't work).

https://youtu.be/YIeRtprJp30

Vicotnik
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Re: Possible to run random cheap fans slowly enough to be qu

Post by Vicotnik » Thu Jul 13, 2017 7:02 am

Yes, cheap fans will most likely do fine. If you will use several fans, it would be good if they were the same model. That way, if you want to control them they would act the same. You could build a simple rheobus fan controller and then tune them as you see fit. Or give them a fixed voltage for simplicity if you have a power supply that will do the job.
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