# Mini Generator? Eh?

Discussion in 'The Projects Forum' started by Lightfire, Apr 17, 2011.

1. ### Lightfire Thread Starter Well-Known Member

Oct 5, 2010
690
21
I saw some videos about creating mini generator.

Um, actually.

it's needed motor, magnets, wires

but cant understand.

what materials do i need? pls specify it.

Instructions???

No, i dont need higher voltage. i just want to see it.

thanks!!!

2. ### Kermit2 AAC Fanatic!

Feb 5, 2010
4,166
1,125
Lightfire likes this.
3. ### Wendy Moderator

Mar 24, 2008
21,416
2,948
A small DC motor will also act like a small generator. The action is reversable.

Lightfire likes this.
4. ### Lightfire Thread Starter Well-Known Member

Oct 5, 2010
690
21
@Kermit2,

The video you have posted was the one that I viewed that I can't understand.

Anyway, it would be possible to make a 12 volts generator? Let's say 12 ampere per hour.

It would be great if it produces AC.

5. ### wayneh Expert

Sep 9, 2010
14,991
5,448
Lightfire, you've made several posts now that are confusing AMPS, an instantaneous measure of current flow, and amp-hours, a cumulative measure of current flow over time and the mathematical product of amps times hours. So your request for "12 ampere per hour" is nonsensical. If it can generate 12A, it can do it forever until it breaks. Don't worry, many people make this mistake. Many are confused about kilowatts and kilowatt-hrs.

Anyway, a 12A generator would be very difficult for a beginner. It would need to resemble the alternator in a car. In fact a used alternator from the junk yard would be a very good starting point. (An automotive alternator generates AC, by the way, but this is converted internally to DC.) A demonstration of lighting an LED is much more practical. And you can do this with many small DC motors. You can also build your own generator. The principle involved was elucidated by Faraday: Moving a magnet past a conductor will generate a current in the conductor. You should read about Faraday and Maxwell at the Wiki regarding magnetism.

6. ### jt6245 Member

Feb 18, 2011
21
4
In low speed revolution, stepper motor is much more easy than dc motor to generate sufficient voltage for demo. If you are using dc motor ,you may need gears or other method to speed up the motion.

7. ### wayneh Expert

Sep 9, 2010
14,991
5,448
With every small DC motor I have tried, a finger spin is enough to pulse an LED.

8. ### Wendy Moderator

Mar 24, 2008
21,416
2,948
Same here. Another good experiment, short the motor and try to spin it (it resists), then remove the short and try again, it should spin much freeier.