ceiling fan

[kenputer]

I put a 30" ceiling fan on an 8' stand with a tail to keep it in the wind and I see it takes very little wind to get it turning,so my question is can these pancake motors be made to make any kind of power. If only my air x would spin a 1/8 as much as the ceiling fan i'd be all set.  Thanks

[johnlm]

Ken,

I opened up one of these ceiling fans one time to see what it would take.  The one I looked at had alot (maybe 16 to 20) poles wound with two separate phases (partially overlapped) with very small sized wire - I estimated one winding was about awg 26 and the other was maybe awg 27 or 28.  Both had alot of turns so I expect one could get a pretty high output voltage at pretty low RPM but the resistance and inductance would be very high.  If I remember one phase measured about 40 Ohms dc and the other about 65 Ohms.  So if used with the stock windings the current you could get out would be pretty low (well under an amp).  One would have to get into the windings and separate each winding coil so you could start hooking them up in parallel to get any useful current.  Otherwise one would have to consider rewinding it with fewer turns of larger wire.

John

[Ungrounded Lightning Rod]

Even if you rewound it you'd be limited by the amount of flux that the cores could take before saturating.

Maybe by stacking the cores from several of 'em you could make something that would pull a nontrivial amount of power from the wind.

[Jerry]

I saw a realy big one at the scrap metal place. Most normal size I've seen look to have a 5" rotor. I think this big one is around 10" to 12" rotor and only has  one set of good size coils.

I'll check it out tommorow. I did put some small NEOs around a stator on some 6" plastic pipe, spun it around a mormal sized unit and got about 75 volt but real low amps. The double rows of coils is strange so I quit messin with that one?

                        JK TAS Jerry