AC Motor to generater

What is it that creates the magnetic field within which the coil rotates to generate electricity (think about it)?

Suggest you go to 'How things work". You can not take just any motor and spin it and expect a voltage output.

....except a permanent magnet DC motor.

Quite.

Or a compound motor. Some are designed to run on AC or DC, and by providing the field with rated current, at rated RPM or a little higher, one should get rated voltage at brushes.

Induction generators of the type you are working on will not give any output unless there is some residual magnetism in the core over which the stator is wound. Looks like the core is completely demagnetised. You may connect a 12v car battery through a switch to the stator windings and give a few impulses of current. There is every likelihood that the motor will start generating after this.

There are web sites that show how this can be done, but you need a lot of knowledge of electricity, just to keep from killing yourself!

If you have that knowledge, then Google the infos you need. I found the following links with one search:-

http://www.otherpower.com/otherpower_experiments_motor_convert.html

http://keelynet.com/interact/archive/00001937.htm

http://users.telenet.be/b0y/

http://www.allaboutcircuits.com/vol_2/chpt_13/7.html

You need to run the motor up to speed as a motor and then drive it faster with another motor, it will then generate. The switching equipment needs to be properly designed to achieve this.....

On top of flashing the motor to insure that there is some residual magnetism in the rotor, remember that induction motors rely on slip to operate. Notice that while a two pole motor should theoretically turn at 3600 rpm (at 60Hz) in reality every induction motor out there actually spins at 3450 rpm. This is due to the rotating magnetic field in the motor(slip). It also works in reverse, you must spin the motor faster than its synchronous rpm (for a 3450 RPM motor, around 3756 rpm) in order for it to generate.

Her is another good page about how to do this: http://www.qsl.net/ns8o/Induction_Generator.html

IanR,

You are correct when relating the output frequency to 60 Hz (3750) i.e. you connect it to a 60 Hz grid. When you spin the same motor at 3450, your output would be at 55 Hz for stand-alone operation; grid connected (60 Hz) it would run as a motor.

If your interested, while your at NS8O's site scroll down to the bottom of the page and return to his main menu. He has done many experiments making generators out of junk. It's an interesting read, at the least.

I think I may have suggested in earlier discussions simply spinning a motor would produce electricity . I thank the above posters for providing the exact method for pulling that off, I remembered it could be done but apparently neglected the need for the field in that discussion I will check out those sights provided and copy and save that info for future reference. Thanks for taking the time to provide those vital links.I hope the original poster is successful .