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speo
Junior Member
Canada
109 Posts |
 Posted - 18/11/2007 : 08:36:47
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Hi guys,
As I promised to Del, here is some bench tests data, collected by myself for an Ametek 30 and for an Indiana 24vdc (rated 24v@375, 0.5Amps on the label).
I think Indiana 24 is a far better generator than Ametek 30.
Ametek 30:
RPM Volts Amps
100 3.36 1.00
200 6.71 2.00
300 10.07 3.00
400 13.24 3.95
500 16.60 4.88
600 19.92 5.85
700 23.24 6.83
Indiana 24:
RPM Volts Amps
100 6.12 1.64
200 12.24 3.28
300 18.36 4.93
400 24.48 6.57
500 30.60 8.21
600 36.72 9.85
700 42.84 11.49
Here are the graphs:
Volts versus RPM
Amps versus RPM
Volts x Amps versus RPM
To me, it looks like I can say Indiana is making three times more power and cuts in at almost half the Ametek's RPM.
www.windpulse.com
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gotwind
Forum Admin
United Kingdom
843 Posts |
Posted - 18/11/2007 : 15:09:55
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Interesting comparison and well illustrated speo.
Ben.
The Futures Green - Getwind of it. |
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speo
Junior Member
Canada
109 Posts |
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Del
Junior Member
United Kingdom
368 Posts |
Posted - 19/11/2007 : 13:21:39
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Hi Speo,
Nicely presented data, very well done. Yes, the Indiana 24VDC looks very good indeed compared to the Ametek 30. My Ametek 30, as you know, has slightly different power charactistics than your version, but it certainly shows up that the Ametek is far from the holy grail of DC motors to use for wind turbines.
I can see you getting asked if you have any of these Indiana 24VDC units for sale on the back of this posting.
All the best mate
Del. |
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speo
Junior Member
Canada
109 Posts |
Posted - 21/11/2007 : 02:25:00
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Thanks Del,
For a much interesting perspective, hook into these graphs the numbers for Ametek 99. Enjoy! I did. I would have post these new graphs, but the numbers for Ametek 99 were collected from the web, not mine.
What amazed me, is that this Indiana motor makes 15V at 250 RPM, while Ametek 99 needs about 400 RPM and my Ametek 30 needs around 450 RPM to make 15V. That means in the 250-400 RPM range, Indiana is making usable power, while both Ameteks doesn't even reach cut in (15V).
Indeed, I received few emails, that's not a problem at all, I use to replay to all emails. Right now, I have only one Indiana 24 that I am not selling, I keep it for myself. I was hoping to get at least two more this week....and still hoping...
All the best
Speo
www.windpulse.com |
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Del
Junior Member
United Kingdom
368 Posts |
Posted - 21/11/2007 : 09:26:48
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Hi Speo,
I did some digging around on the Ametek 99 unit and posted the following a few months ago.
BTW, have you had any experience of Clifton motors?
There seems to be some conflicting info about the Ametek 99VDC around.
Take a peek at the following (both from tlgwindpower)
http://tlgwindpower.com/ametek.htm
This one says it makes 99v at 535 rpm but if you click on th output data link you get this page
http://tlgwindpower.com/Ametek99data.htm
This page says it's only getting into charge territory at 350rpm.
Just done a bit more googling - check this data out
http://www.fieldlines.com/story/2004/4/23/13245/9108
535rpm is not correct. It needs 2156rpm to achive its V max. Therefore, 13v is gonna need 300rpm. So the boss may not be all it's cracked up to be after all.
Cheers
Del.
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ghurd
Junior Member
USA
304 Posts |
Posted - 21/11/2007 : 16:11:02
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Be careful rating a motor only by the cut in RPMs.
Matching blades to the RPM and power is whats important.
Too low cutin on a small motor will give problems with stall unless the blades are oversized and slow, etc.
Its a balancing act I rarely get right.
G- |
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Del
Junior Member
United Kingdom
368 Posts |
Posted - 21/11/2007 : 17:12:29
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Good point well made Ghurd.
We can all make lots of blade configurations of number, length, profile, shape, etc etc, but what is important is matching them up to the optimum of your generator. Of course the available wind also needs to be taken into account and if your optimum rpm is higher than the available wind you have then you may be able to go for a blade set-up that makes the best use of the wind you have.
Cheers
Del. |
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speo
Junior Member
Canada
109 Posts |
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speo
Junior Member
Canada
109 Posts |
Posted - 21/11/2007 : 19:20:09
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Thanks for the links Del.
You are right, the 99v at 535 label does not match with the bench test data. I might say something stupid...maybe the meaning of the label be that the voltage is 99V and the RPM is 535 under load, hooked to the device it was designed to be used?
Speo
www.windpulse.com |
Edited by - speo on 22/11/2007 03:45:23 |
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Mertz
Starting Member
USA
42 Posts |
Posted - 10/12/2007 : 20:58:57
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I bought one of the Indiana 24v and have the motor mounted but not flying yet. I also have a Ametek 30 flying. Hopefully both will be flying at the same time next weekend. I will be able to give everyone a good comparision using the same height tower and the same wind speed. I think the Indiana will preform much better just based on my bench tests. I can stop the Indiana in a slight breeze by shorting it out but I can't with the Ametek. I will keep you posted.
Mertz |
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speo
Junior Member
Canada
109 Posts |
Posted - 12/12/2007 : 21:32:25
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Mertz,
Please keep us posted. We should keep in mind how well both sets of blades are matched to the generators. I think that's something we can just estimate and I'm worried how far from the truth the estimates will be, especially if your blades are PVC, not wood.
I can't wait to see the numbers.
Speo
www.windpulse.com |
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Mertz
Starting Member
USA
42 Posts |
Posted - 13/12/2007 : 00:34:13
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If someone would like to donate an identical set of blades we should get some pretty good numbers. It will be a little while until I can build a matched set. Probably after Christmas unless I can find some more free 6" sewer pipe.
I will let everyone one know what results I get with what I have now. Hope to get the Indiana flying this weekend.
Mertz |
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Mertz
Starting Member
USA
42 Posts |
Posted - 17/12/2007 : 15:57:08
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I got both the Indiana24 and the Ametek30 flying this weekend. There hasn't been any real good wind but from what we had it appears the Indiana is considerably better. I had the Ametek flying with a 2 bladed 30" prop and the Indiana with 3 blades @ 27". The Ametek was spinning much faster than the Indiana but the Indiana produced more voltage. I will take some more readings when we get a better wind. With the wind we had both were producing in the 3 to 4 volt range under a slight breeze. It was enough to power some 12v Christmas lights.
Mertz |
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speo
Junior Member
Canada
109 Posts |
Posted - 17/12/2007 : 17:07:13
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Hi Mertz
2 bladed 30" prop - is that diameter or radius?
3 blades @ 27" - is that diameter or radius?
The Ametek needs a diameter of 4'
I'm not sure yet, but I think the Indiana needs a diameter of about 1.7 meters, which is about 67 inches
My estimates are for 3 wooden blades.
Speo
www.windpulse.com |
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Mertz
Starting Member
USA
42 Posts |
Posted - 17/12/2007 : 21:17:20
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Both are radius. It tried using a 40" radius on the Ametek and it was to slow so I cut them down and put them on the Indiana. Total diameter for the Indiana is 64". I am using only 2 blades on the Ametek because I dropped it and broke a blade. I will go back to 3 when I find some more pipe.
Mertz |
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Ametek 30 and Indiana 24 data comparison
