"Contactless Dynamo" / Wind generator showing weird multimeter readings?

I am trying to replicate this, more or less, It's a setup using hard drive magnets and the coil from a relay to generate electricity.  My problem is that every configuration I have tried gives me weird negative and positive numbers(around -20  to 20, constantly changing while the magnets are spinning), and only in the hundredths of volts setting(on the multimeter, the volt, and thousands of a volt settings show nothing).  I have tried using: hdd magnets and round magnets (8 of them in a N-S-N configuration);  a relay coil, a small transformer coil, and winding my own coils 3 times.  The hand-wound coils have approx. 159 turns, 200 turn, and 250 turns, all with thin very thin enamel-coated wire, as it's my understanding that thinner wire will output more voltage.  No matter what configuration, I get the same erratic readings.  What am I doing incorrectly?

That's the way its suppose to work. As the N side passes the coil it sends electrons in one direction then when the S side passes it sends the electrons in the other direction. You have created a small AC generator. To get adequate power you will need to drastically increase the RPMs and use a bridge rectifier to convert the AC voltage into DC. Or set up the magnets so only a single pole is facing the coils. That won't be possible with HDD magnets since one half of the face of the magnet is N and the other half is S. You will get eratic voltage if you are unable to maintain a constant rotation.

The project you linked to rewires the LEDs into a configuration that uses the LEDs as a rectifier. So while the current flows in one direction one set of LEDs light and when the current flow in the other direction the other LEDs light.

The thickness of the wire doesn't determine voltage output. The overall thickness of the wire combined with number of turns, how large the magnet is and how many times a second the magnet pass by the coil determines overall voltage and current available. The main key is getting the RPMs up and reducing the distance between coils and magnets. You will want to use multiple magnets and coils for best result. The more you have the more power you will get out of the system to a point.
chrispaccord (author)  mpilchfamily4 years ago
Thank you for putting in clearly!