12 volts??

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12 volts??

Post by unjonharley » Tue Jul 20, 2010 5:38 pm

I have a razor scooter motor.. I can get 5v DC when I spin it with a drill motor..

Will the volts go up with more speed??

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Post by oneeyeddick » Tue Jul 20, 2010 5:44 pm

hook it up to your side grinder and find out
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Post by Token » Tue Jul 20, 2010 5:45 pm

Try a Dremel. See what happens. Best stick a light bulb or some kind of load on it then measure.

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Post by mudpuppy000 » Tue Jul 20, 2010 6:07 pm

Or set the drill at 1/2 speed and see if the voltage drops. :)

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Re: 12 volts??

Post by Zhust » Tue Jul 20, 2010 7:39 pm

unjonharley wrote:Will the volts go up with more speed??
Yes, but you probably don't want to go much faster than 25% over the maximum speed the motor was designed to run at. I'd wager that if it's a 12-volt motor, you'll probably get 12 volts as a generator until you're in the 3x range above the original maximum RPM.

Some "universal AC/DC" motors work as generators. Some electric lawnmowers I've seen use a 150V DC motor with a bridge rectifier (the Black-and-Decker ones that short out the motor to stall it when you let go of the trigger), and they work as generators. I also found a junked 120VAC electric string trimmer and when I ran the motor on my drill press, I could get it to produce usable power above 12 volts -- enough that it seemed plausible to use that as a generator. In general, if a motor "cogs" (snaps to angular positions) it has magnets which makes it a candidate for a generator.
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Post by Bluemandrew » Wed Jul 21, 2010 5:57 am

A Burner from Boston is working on a really impressive project this year called lowRes http://lowres.info/

He's using brushless bike hub motors as generators, as they're built for a lower rpm
This weekend I’ll set it up so I can actually sit and pedal, but I was able to get 100 watts (~13 volts @ 9 amps) without too much effort pedaling with my arms.
Seems promising.

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