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Re: DC power supply
> Well, I really didn't think he wanted to fly the hood. What you do not
> understand is that once you start to build a power supply, there is no
> particular savings to build one rated at less than 3 or 4 amps. If the fan
If you look at the small 12v or 5v fans, they use far less than even 1 amp.
The largest current draw I saw was a 12v fan that draw 350ma, and moved 85cfm.
And at those low currents, simple wall-wart transformers work perfectly. They
don't need good regulation. They are just spinning a fan. I've already
priced two or three different suitable 12v or 5v power supplies for under
$5.00 each. There are several cheap 12v power supplies that will provide
> store. Incidentally, why not just buy a 115 VAC muffin fan? That doesn't
> require any power supply at all, and moves more air to boot.
I like the dc ones. Typically less noise, and a cheap $3.00
wire-wound pot can be used to control the speed. Also, because the
low voltage and low current, I have no fear suggesting to beginners that
they wire this up themselves. I've dropped my low-voltage LED lights
into the tank before while they were on, no problems.
Only downside to the DC wall-warts is that they take up too much
space on the powerstrips.