OH thanks Tom &Ed.
Several years ago I discovered this site thanks to Richard Perez of the Home Power Mag (thanks Richard).
It was my introduction to ac motor conversion. Back then I started a search for free ac motors.
My sources were (and still are) plumming shops, heating & airconditioning shops, motor rewind shops ect.
I've collected around 1,000 motors FREE. I've converted many diferant types.
The easyest and most plentyfull and with very good results have been garbage disposal motors.
Reasons why. These motors are designed for intermitant use, short time on.
Also these motors have an unusually large bore for the hp rating. This larger diameter creates fast magnet speed past the coils for higher output.
They are also wound fairly loose. This permits easy seperation of coil wire ends.
Its very easy to seperate all 8 coils. 4 starts & 4 runs. Reason for coil seperation.
These are 120v motors. They have 4 run or main coils. These coils are wired in siries. This means each coil is a 30 volt coil. If we were taliking about a 1 hp motor its is rated at 10 amps. BTW 10 amps X 120v = 1200 watts.
We know each coil is a 10 amp coil. If we perelelled all the run coils the motor would be a 30 volt 40 amp motor. BTW 30v X 40 amps = 1200 watts.
In terms of useing the motor as a PMA 30 volt is closer to 12v and 40 amps is better than 10 amps. Problem is we would need to spin the motor faster than the expected blade rpm to work well as a wind genny. So we do a comprimize and do a siries perelell combination on the coils.
This can also be done on the start windings. Since they are out of phase with the runs they must have there own and seperate fullwave bridge rectifier.
Then end result is a two phase pma. This further reduces rpm requierments.
Most motors are baked in varnish and dificult to work with. Not so garbage disposal motors.
BTW the 1 hp are extreamly rare. There are many 1/2, 1/3, 5/8 and 3/4 hp. the higher the hp the higher the power.
Wind test data on a 1/2HP.
5 mph 2 amps, 10 mph 5 amps, 15 mph 8 amps, 20 mph 12 amps, 25 mph 23 amps, 30 mph 26 amps
A 1/3 hp would be slightly less.
JK TAS Jerry
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