Fan motor

Just a quick question from someone who is completely electronically
inept.

I want to put together a quick science fair experiment, and I was
wondering if I could use a scrap fan motor in order to generate
electricity?

What I mean to say is, provided I can find a way to turn it (wind or
water power) is it difficult to coax a recycled motor component into
generating electricity?

 

a 12vdc fan from a PC would need some modifying,
youd probably need to take it apart and replace the electroncs with a
rectifier.

other types of fans such as AC mains types are induction type wich are not
very convenient generators.

Colin =^.^=

 

colin inscribed thus:

You could always pull an old CD Drive apart ! There are at least
three motors in there that will all generate an output voltage if you
spin the shaft.

For example I am using a salvaged tray motor as a wind speed
generator ! It will produce nearly three volts on a good day.

 

Don't mess with an unknown fan - these days, they're not like motors used
to be, assuming you're talking about computer fans.

For a science fair project, get a hobby motor for two or three bucks:

http://www.radioshack.com/search/index.jsp?kwCatId=&kw=motor&origkw=motor&sr=1
http://scientificsonline.com/product.asp?pn=3082264&bhcd2=1181939310

These, being permanent magnet motors, will not only reliably generate DC,
but can show speed/torque/voltage/current relationships with a couple of
meters and a little analysis, which should really dazzle the judges.

Heck, why not give them a hand crank for a _real_ hands-on display?

Have Fun!
Rich

 

Well its not a computer fan, I was actually hoping to use an old room
fan (the kind you can pickup and move around) Since I happen to have a
junker on hand....

A neat idea, but the idea I'm going for is to recycle as much as I
possibly can.... I want to demonstrate and measure how effectively a
homes electrical costs can be offset (and If I can use junk parts to
do this, then all the better!). A crank is a neat idea too! I might
add one in, just for flare but right now, I wanna see about
getting it to run on natural resources, and if necesary, but having a
flow run from a pair of buckets that can be raised or lowered, and
then swaped.

Hope I can keep getting more usefull ideas!

Oh, by the way, I also have a junker freezer, could the compressor
motor be scavanged?

 

In general motors intended for AC mains power will be more difficult to use
as generators, so avoid them.

In principle any permanent magnet DC motor will do, for example from a R/C
car, tape recorded, or the radiator fan motor of an old car, but you would
need a lot of RPMs to get a decent voltage with any of these.

You might find that big stepper motors out of old printers (e.g. from the
dump) are a good way of generating reasonable voltages without requiring
high RPMs. With stepper motors, what comes out will be AC. You might need
to experiment to find which wires are connected to the same winding using
an ohm meter. If you want to power a light bulb then the fact that it is
AC won't matter, but to run a radio etc. you will need a rectifier and
smoothing capacitor, and ideally a zener shunt regulator or similar.

Chris

 

I assumed he wanted it to have a fan to be able to turn it with the wind,
if not then any brushed dc motor would be easier,
they are so cheap from many hobby shops for models rc, electronics etc,
I gues the one your refering to is a brushed type.

so is it any use when theres a power cut or anything ?

Colin =^.^=

 

Sorry, AC induction motors don't generate voltage if you just spin
them. You need a permanent-magnet brush-type DC motor. Some little
battery-powered fan might work. Don't expect much power.

John

 

not easily, a microwave oven platter motor on the other hand makes
an excellent hand-cranked generator, but the output voltage is kind
of high.

permanent magnet motors work best

Bye.
Jasen