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joyt12k

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Joined: 12/05/2009
Location: Australia
Posts: 49

Posted: 01:06pm 20 Sep 2010

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Hi, has anyone tried the carbon fiber Raptor blades from America on a F&P, they come in 3,5,7,9,and 11 also any views on their PMA?

jasmine

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 01:29pm 20 Sep 2010

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Hi Jasmine

I have a few sets I tried, from 3 to 11 blades and found that they are very effective in over 8 ms winds but below 6 ms they are pretty useless unless the generator is 200 watts or less. They are quiet and smooth running after you trim the blades and balance them.

I plan to use them on 600 watt non furling machines, and that's the reason of getting a few to try, the 5 blade is the minimum that works on those, with the 11 blade a bit better. they will run up to 2000 rpm which is what I wanted.

For the F&P you would need the 11 blade I think, as the starting torque is low on the lesser blade sets and it doesn't spin as fast but maybe still to fast for the F&P.

I haven,t used their alternator PMA type but found that automotive alternators in general need more rpm than wind turbine blades are capable of delivering, one 65 amp 12 volt unit PMA I tried needed 3500 rpm to get any useful out put an 5500 to get 45 amps.

All the best

Bob

Foolin Around

joyt12k

Regular Member

Joined: 12/05/2009
Location: Australia
Posts: 49

Posted: 08:49am 21 Sep 2010

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Hi Bob, I have just bought seven blades with the hub, I can always buy more, they were $21.00 ea and $15.00 for postage, very reasonable. Will try them out as soon as they arrive.
Do you happen to know why their PMA mills and blades are designed without furling?

jasmine

dwyer
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Joined: 19/09/2005
Location: Australia
Posts: 574

Posted: 11:02am 21 Sep 2010

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Hi Joyt12k
Do you happen to know why their PMA mills and blades are designed without furling?

They have solid state electronic regulater just like normal automotive alternators so no need furling

Dwyer the bushman

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 11:22am 21 Sep 2010

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Hi Jazmine

The PMA works at much higher RPM than other alternators so the high speed blades are a good driver and no need to furl as the alternator can work faster than the blades can go.
That is the combination I am putting together as I dont like furling, have a look at Karls latest post and you will see the results of constant furling.

All the best

Bob

Foolin Around

joyt12k

Regular Member

Joined: 12/05/2009
Location: Australia
Posts: 49

Posted: 01:41pm 21 Sep 2010

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Thanks Bob, looks like the way to go, if these blades don't work with my F&P I'll be buying one of their PMA's.
I'm looking to achieve around 18 amps, don't suppose you know what rpm roughly
would be needed? Have seen their graph but would prefer hearing from someone whose tried it.

jasmine

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 09:36pm 21 Sep 2010

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Hi Jasmine

I haven't tried one of their alternators as the one I had was one off a tractor, it needed a lot more rpm than they state for their conversion, I was going to get one of theirs to try but didn't get around to doing it, to many projects on the go ,and I decided to get one of Phills lower speed machines as that suits my wind speed at this location better.

A friend of mine got one with a six blade but due to the small diameter it takes a strong wind to get 30 amps at 12 volt. He hasn't got a wind speed for me, but I think it is like mine and is above 8 ms.

If you have that kind of wind then they will perform but if you have lower speed you would be better off with a larger diameter 2.5 to 2.8 meter. Have a look at Altons chart of propellers for an indication
http://www.alton-moore.net/wind_calculations.php

It wont work with the high speed blades like Raptor but is a good indicator on slow blades.

All the best

Bob

Foolin Around

joyt12k

Regular Member

Joined: 12/05/2009
Location: Australia
Posts: 49

Posted: 01:11am 02 Oct 2010

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I've given up with the F&P for now and have just bought the Super Victory PMA.
They recomended the 24v 1500watt one to achieve what I want, that is between 15 to 20amps at around 300RMM, if higher I would be more than happy. The 7 blades should arrive middle of next week so I'll try them on the F&P, somehow I have my doubts that's why I bought their PMA. Will keep you all posted.

jasmine

joyt12k

Regular Member

Joined: 12/05/2009
Location: Australia
Posts: 49

Posted: 11:35pm 08 Oct 2010

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Looks like the postal service in the States is crap, it's been 3 weeks, and still waiting for delivery of my blades, as for the PMA that's been a week since odering
and they hav'nt posted it yet.

jasmine

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 11:57pm 08 Oct 2010

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Hi Jasmine

I have found that it takes a month to get things from the USA so don't dispare.

I will be very interested on your results with the Raptor blades and the PMA 24 volt unit,

All the best

Bob

Foolin Around

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