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brucedownunder2
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Joined: 14/09/2005
Location: Australia
Posts: 1548

Posted: 08:05pm 24 Oct 2006

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I think I'm confused to a point where I need your help.

I've re-configured 2 stators in the 7 phase configuration but don't see very much performance .

I have done the 48 Neo magnet conversion and it is what I suspect that is wrong ??.

No Cogging at all and turning by hand fairly quickly I only get around 10 volts out of the 7 phase rectifier.

I've put it on the 65 foot tower ,but as usual no wind since hoisting .

Ok, any idea's what could be wrong??

Bruce

Bushboy

Gizmo

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Joined: 05/06/2004
Location: Australia
Posts: 5078

Posted: 08:57pm 24 Oct 2006

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Hiya Bruce.

Its all about fault finding. First up, we know the conversion works, I have one and its making more power than a standard 3 phase conversion.

You have 2 unknowns, the stator re-wire and the Neo conversion on the hub. You need to eliminate one, the Neo conversion. Go and buy one of the new hubs, they are only cheap and will tell you if its the stator rewire or the neo conversion.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

Gizmo

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Location: Australia
Posts: 5078

Posted: 09:22pm 24 Oct 2006

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And looking at the figures, 10 volts is way less than I would expect for a Neo conversion.

I take it you wired the stator as a 7p2p. I would put a AC meter across one coil and spin the hub, record the volts, then put the meter across two coils in series ( 7 poles apart, one phase ) and measure the volts, should be double the first reading. Thats one phase measured, and the other 6 phases should be the same.

On the hub check that the poles are right, you have 2 magnets side by side for each pole, make sure they are NN or SS, and not mixed up with a NS on each pole.

Glenn

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

brucedownunder2
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Joined: 14/09/2005
Location: Australia
Posts: 1548

Posted: 10:01pm 24 Oct 2006

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Thanks Glenn. went for a 5Km walk and thought about it . I 've got it --stupid me has the magnets wrong --so, out they come and correct my mistake .

I thought so, ...

I have ordered a new F&P rotor hub . It will be here in a couple days ..

Now out to lower the mill --no wind ,so it's not a drama.

Bruce

Bushboy

Gizmo

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Location: Australia
Posts: 5078

Posted: 11:41pm 24 Oct 2006

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Good to hear Bruce. I will be happy when someone else get a 7 phase F&P working. My conversion is working great, and I know this is the easy fix to the F&P cog problem.

Let us know how you go.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

brucedownunder2
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Joined: 14/09/2005
Location: Australia
Posts: 1548

Posted: 08:18pm 25 Oct 2006

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Well, I've removed all the maggots and nearly cleaned them (what a bugger ) . I've positioned half of them ,this time correct-- NN SS NN SS . What I had was NS NS NS and so they were cancelling each out as they passed over the stator "Pole" . Bugger .
So I was getting just a few volts . the cogging was way down and maybe will be even better when I'm finished this correct set-up ?
Should be finished today .

Bruce

Bushboy

Saaremaa

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Joined: 10/12/2005
Location: Australia
Posts: 13

Posted: 10:25pm 25 Oct 2006

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Bruce - do you mean you were using groups of two smaller neo magnets in place of one larger one for each magnet position? i.e. 96 smaller magnets instead of the 48 required?

For interest's sake here's a link to an interesting article on PM motors. Towards the bottom of the page it mentions F&P motors - and also shows a picture of their new factory in Ohio. So US folk may get the chance far sooner to collect the motors for free from council clean-ups.
http://www.appliancemagazine.com/zones/supplier/18_motor_mfg /editorial.php?article=1561&zone=18&first=1

also, F&P's motor patent drawings:

http://www.freepatentsonline.com/5821708.pdf

[ Hope you dont mind, changed those link to clickable, Gizmo ]Edited by Gizmo 2006-10-27

Saaremaa

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Joined: 10/12/2005
Location: Australia
Posts: 13

Posted: 11:13pm 25 Oct 2006

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p.s. - notice in that article that F&P actually used to use Neo magnets in the rotor but went to ceramic because they were stronger and cheaper.

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