PMA's any good???

[vwgtiman]

I am the owner of a Wind Blue 540 PMA.  I see a lot of bad reviews on this product.  Can anyone tell me if there is a positive to it?  Should I sell and redistribute funds in something else.  The PMA platform seemed like a good start to get into wind power.  I was going to mate it with a TLG rotor or possibly one from Windy Nation but have been waiting until I get my tower up.  Here are my main questions:

Are PMA's useful at all?

If so, who out there has one that actually gets use from it?  Any photos?  What rotor do you use?

What is the difference between the various PMA builders out there like Wind Blue, Hornet, Mallard, Hurricane (this is a new one I see now, they have some sort of dual PMA; looks like a alternator with an extension in the middle…)?

Thanks everyone!

http://www.windbluepower.com/
http://mikeswindmillshop.com/PMA.html
http://www.hurricanewindpower.com/servlet/the-175/wind-generator,-pma,-delco/Detail
http://www.missouriwindandsolar.com/PMA_S_and_Parts.html
http://www.survivalunlimited.com/windpower/pmas.htm
and on and on......

[DanB]

I could be wrong here, but my take on it is that all these PMA's you mention are modified car alternators ~ some of the ones you mention, although they are sold by different folks and probably made by the same people and identical.

I expect they are just fine so long as you understand that they are small PMA's.  PMA's are very good for wind power... but if you get a very small one (a modified car alternator) then you'll have a very small wind turbine.

The trick is to match them up with the right blades.  I don't think you'll ever get a very good wind turbine from a modified car alternator (unless it's very small).

I believe the common 'Air' series of wind turbines from SW wind power uses (or started out using) a modified car alternator stator with a permanent magnet rotor inside it.  For it's size (about 4' diameter) it works reasonably well.

Do be careful though - some of these are promoted with quite a lot of hype in my opinion.  Some of the sellers will imply that the power you can get from one of these at any given rpm is as simple as multiplying open voltage by short circuit current which is absolutely misleading.

A modified car alternator can be used to make a decent 'tiny' wind turbine but it's going to be very limited in my opinion.  

So to directly answer your question... sure - it might be good.  Depends on what you want.  The term however 'PMA' (permanent magnet alternator) does not only  apply to the products you mentioned... there are lots of very good (and many are home made) PMA's out there that can be quite powerful.  Some of the ones you mention are suitable for very small wind turbines and should probably work fine so long as you match them with the right blades and load them properly.

[Fused]

I have a Wind Blue pma. I made over 15 sets of blades trying to get it to charge a single battery. I admit Im in a poor wind zone but we had plenty of storms with high winds to get a feel for what it could do. You will need a very high wind zone to actually get any useful charging. Wind Blue advertises shorted amps and open volts which is misleading to many just starting out in wind energy production. The best use I could come up for my WB was to connect it to a gas engine for a generator to recharge my battery bank (430ah now). The resistance in the windings of a 540 seems to kill the output. These are just my findings, others may differ.

http://s298.photobucket.com/albums/mm249/Southbuck7/?action=view&current=IMG_0427.jpg

http://s298.photobucket.com/albums/mm249/Southbuck7/?action=view&current=TLGblades.flv

http://s298.photobucket.com/albums/mm249/Southbuck7/?action=view&current=IMG_0410.jpg

Good luck
Fused

[vwgtiman]

Thanks.

Fused, are any of them sets of blades purchased?  The TLG site says the Boast Buster rotor wil work well and reviews seemed good.  I made a set of PVC blades and had it up on a post but a week in they were all laying in random places in the yard......

I guess I am going to put it up anyway.  It will be a good learning experience.  I am getting the tower tomorrow so in the next few weeks I may put it up.  I only figured I would use it with a low cost charge controller to maintain a battery on my diesel generator project...  (a Lister Petter TS2 w6 kva head)

I was also thinking of using the batt for possibly some LED lighting in the garage or for running a pump on a timer on my hydroponics project.

[Fused]

http://www.windbluepower.com/TLG_Cy_Clone_5_Foot_Rotor_w_Stainless_Steel_Hub_p/tlg-cy-clone%20ss.htm

These are the blades I purchased, and the blades in the video. I traded those blades for parts to build a dual rotor axial flux machine.

I cant find my uploaded files here yet.....it had a pic of the 15+ sets of blades I made for the WB.  

I should mention, I had to separate the windings in the WB stator and I had to use a larger wire gauge stator to make the gas generator function at 24v for my present battery bank. I believe it was the high wind stator from wind blew that Im running now. The gas generator will put 15-35a into the 24v set up as it is. Almost over kill at a idle or just above idle.

Hope it helps.

Fused

(ghurd attempting to learn... but if nothing in there would do it, I doubt anything would be much better)

[Fused]

Geeze, Im a blabber mouth today.....

I should mention that when I was trying the Wind Blue out I was running it on a 12v system. The best I seen on the meter was 3a during a tropical storm which is only about 40 watts.

When you get ready for a controller, you may want to write the moderator of "controls" Ghurd sells a very inexpensive controller kit that works very well. www.ghurd.info

I hope that link is right. 

Fused

aka Doug

[Beaufort]

I have a DC-540...it needs a set of very fast blades like the ones on their website or TLG's.  As you mention, there is a bit of start-up torque required which is not the case with an axial flux.  Maybe a gear-up arrangement would get more out of it but then you lose power in the transmission.  I've read that hydro applications suit this one well, but you can't just carve up a set of blades and expect 100W out of it.  Right now it's sitting gathering dust.

I'm seeing some super-modified alternators on Ebay that appear to have a middle section added with more magnets and wire.  Of course, the claims of 2-3 Kw out of them needs to be checked, but it's an interesting idea to get more out of something that's off-the-shelf.  I'll stick to axial flux for wind.

[DanB]

YOu say 'very fast'.  I wonder 'how fast' 

It would be interesting to know what the 'cutin' speed is for your alternator... in otherwords, at what rpm does it reach battery voltage.

In my opinion, PVC, or aluminum TLG blades are not likely to be 'very fast' - for very fast blades I'd carve some slender wooden ones.  That said - I've not personally tried TLG blades and I gave up on the idea of PVC a long time ago - I think it's OK for messing around with but I really doubt you'll make PVC blades that work very well or last very long.  Part of me kind of wishes the whole idea would just go away but that is just my opinion. 

[vwgtiman]

Thanks guys.  My curiosity has me looking deeper now...

Per the website of the DC512 (I am a customer that has paid for this so I dont feel bad asking this on a forum) is this statement:

For use as a direct drive wind generator, select a fast set of blades and you should start charging a 12 volt battery setup in about 6 mph winds. This unit passes the 12 volt mark at just 130 RPM. The “Cy-Clone” rotor from windbluepower.com is a good choice. Many other websites offer good rotor designs and even plans for rotors if you would like to build your own, just make sure it has a 17mm hub to fit a standard Delco alternator shaft.

What is missing here then?  Is it that none of the blades out there get up to or above 130 RPM consistantly?  Or is this 6mph and 130 RPM BS?  $235 bucks is $235 bucks.........

[DanB]

If 12V is the goal...
then 135 rpm is really fairly slow for such small machines.

The 4' diameter Air 403 from SW windpower cuts in (reaches battery voltage) at about 400 rpm

Our 10' diameter wind turbines that we build cut in at about 140 rpm.

If it reaches 12V at 135, then I would probably lean towards using such alternator with fairly slow blades (like the TLG ones probably are) on a 24 volt battery perhaps.

It's really somewhat tricky to get it working well - you really need to match the load to the blades and that is the job of the alternator. 

It's tricky to just get an alternator and stick whatever blades on it and hope for good results. 

[vwgtiman]

I am curious about the 10" diameter turbines you build.  Are these the axial flux build I see alot of?  I dont have much time for winding coils and gluing magnets otherwise it seems like it would be fun and I would have a nice unit in the end...  can parts be purchased? 

[Rover]

I'm very skeptical of any claims of small PMAs (car alts, treadmill motors, ECM conversions) cutting in at at less than 200 RPM, most are in the 300 + range sometime 500rpm or more.

Having owned an Air-x , It takes quite a bad of wind and 600rpm ( in my hands) , to do anything, I definetly don't recommend it.

 

[bob g]

any alternator manufacture or reseller that does not certify the following should be looked at with great suspicion

1. at what rpm is the the following test results

2. voltage, and

3. amperage at that speed and voltage

stating peak voltage, at some unknown and often insanely high rpm, and then stating dead short amperage, is just not
at all honest and those numbers are worthless.

for a flooded lead acid battery i am  (12volt nominal) i am looking for how many amps at 14.4volts (min) at what rpm
and having been ran long enough to be thermally stable.

i build custom automotive alternators, any of which will eat for lunch any of these pma modified car alternator in
any area one wants, peak power, thermally stable power, amperage and/or voltage.

btw none of them are pm alternators.

i can't tell you how many dissatisfied folks i have ran into over the years duped by these wild claims of the pma snake oil salesman.

this is not to say that there is not a single pma auto alternator that does anything like what is claimed, it is just that i have never seen one yet.

personally i can find no redeeming quality that would make me want to part with any significant amount of money purchasing one.

ymmv, however

in my opinion for the money spent a small aircore unit would outperform any of these pma auto alternators without any trouble.

bob g

[Rover]

I concur, having owned ECMs, air-x, treadmill motors (generators)) ... there are things to look at in this categoriy and first off is the category itself. These are are high speed gens/alts,  they need small rotor diameters with fast blades. The draw back?... smalll rotor/blade diameters, you can only capture a smaller portion of the wind since you can't get the rpm from larger blade sets.  The plus is they are cheaper, they "can work" , I have a few... and  yes the generate... but you have to know what you are looking for (I'd take a GE ECM (with some re-wiring work) or a treadmill motor with the proper specs, over any car alt sold on ebay with dubious specs.

None int this category will never conituously generate as much as a larger axial flux, or (larger) good quality commercial.

but I still love working with em.
 

[ghurd]

I have a set of TLG Cy Clone blades.  They are Slow.  Kind of look like PVC blades if made from maybe 18" pipe?
Probably better suited to a 5 blade than a 2 blade.

Pretty easy to get any cut in RPM desired, but it is often a bad idea. 
Can easily connect up an ECM for below 120RPM cut in, but that doesn't mean it is a good way to get power out of it.

G-

[tecker]

Ok I think we have established from previous posts that the you need a voltae rating in the range of 200 volts to get a good return on your investment on a Dc motor for a genset:::: but and   that's a big thing the But .But you can strip the mags from the field and do a neo convertion to get the the cutin lower it's the same deal as the zubbly button install I have a small dc motor that is doing well with this mod just hammer out the ceramics and cast in some neos with the same polarity .
I can here it now that )(*^ is wanting me to destroy this motor and yep that's what you do .Try it on a smaller motor and check it out first it you feel more comfortable but that's the gig Swap  out the mags for more flux in the field.

[bob g]

i may at times take a rather harsh view of pma's in general

usually my attitude comes from wild claims of high output from those that solicit sales of modified car alternators
while they do work, in a fashion, they do so at a very high cost per watt returned in my opinion.

seems like the sell for 250bucks and up, and for that money one could do a Zubbly conversion and get something much
more useful, or build an aircore and do even better.

there is nothing to be gained by purchasing a pma car alternator to be attached to a gas or diesel engine, what little you might
gain in reduced field current is more than made up for in increased complexity of charge control. and unless you have very good
controls to keep the amps and voltage setpoints right, you will be babysitting the charging of your batteries or risk overheating
or damaging something sooner than later.

its just that there is so much good info here on this forum that one should avail themselves too, that is makes no sense to me
to try and take a shortcut with some jokers pma car alternator unless it can be bought for well under a hundred bucks, and
one expects to have to work very hard to get a fast enough blade set, and does not expect any real amounts of power from  the
machine "except" for a few moments in a catagory 5 hurricane.

seems to me the ad copy of most of these types of alternators is worded specifically for those that have not educated themselves
and is directed at parting the less informed with as much money as is possible.

bob g

[WoodWaterWheel]

I've been using Wind Blue PMAs for several years in hydro applications and have tested these PMAs using a giant metal lathe to check their power outputs at set rpms and if anything I've found their claims to be more than honest.          I saw 12.2v out of one of their model 540s at 57 rpm and their amp/watt output claims are accurate at set rpms.       My units require fans because they aren't 70' up in the air for cooling and cooling seems to be the primary problem for any small PMA like the ones using automotive alternator cases.          Be realistic,       The 540 as with any other very low rpm altenator in a small automotive type casing will be limited in how many amps you can pull with the mininum cooling from low wind speeds.      My customers have all been happy with the Wind Blue PMA's.        What is needed for those of us who sometimes want a 1000+ watt 12v PMA is someone to develop a larger bodied unit for a low price.       But as long as people (me included) keep searching for this 1000w  12v  PMA for less than $300 we will never see a reliable one.       For my money the Wind Blue PMA is the best unit I've run across in this price range.
P.S.      If someone does come out with a sub $350 very reliable PMA that can make a 750w 12v at 1500 rpm PMA for less than $350 I could give them some business but until then I'll stick with Wind Blue.
Spencer