Author Topic: Vawt update  (Read 9446 times)

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disaray1

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Re: Vawt update
« Reply #33 on: November 10, 2007, 05:54:12 AM »
 Thanks, Ed. I've looked around your site before, but never saw this page... :)


 Take care!


 David

« Last Edit: November 10, 2007, 05:54:12 AM by disaray1 »

CmeBREW

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Re: Vawt update
« Reply #34 on: November 10, 2007, 07:12:53 PM »
I re-did that alternator 'crank' test just now. I wanted to test the current I could get from EACH phase. That might not be the most accurate way of saying it though, since, I believe there are always 2 phases in series at any one time. (STAR hooked)

Anyway, I alternated using only 2 of the 3 wires at any one time thru the bridge rectifier(s), to see if there was any difference in current going into the battery.  There was no difference. All combinations are the same. (about HALF the amps of all 3 phases hooked up at once)


I also believe I mis-judged the first crank test quite a bit. At that 2 foot diameter, I could only turn the crank so fast (rpm)-- and I now think THAT was the most stressing part on my arm....not the torque resistance of the alternator. It is a difficult think to judge. It seems to mainly work the forearm.


So I brought the crank inward clear down to only 4 inches away from the center point.

I can still crank 3 amps steady, cranking it at only 4 inches. It is not extremely difficult to do so-- but its not too easy either. It  still feels more than the formula ED mentioned though--- but who knows.  

I know now that 1 amp is fairly easy to crank at around 100rpm.  So I think the alternator is working good enough for more vawt tests.


I have got the time to do several more tests, primarily with the smaller proto-type vawt rotor.  It is looking better. I may have better results very soon.          -Thanks.

« Last Edit: November 10, 2007, 07:12:53 PM by CmeBREW »