First fly on test tower

[wooferhound]

while we're on the subject of batteries, how do you calculate how many you should have for a given turbine?  i know i've seen this sort of stuff around, but i've not been having good luck w/ the search engine lately.

Here is a story that covers Watts of power to Battery Amphours
It was asked in the Solar area but I'm sure that it would have some application to wind power
http://fieldlines.com/board/index.php/topic,135698.0.html

[poco dinero]

Hi Dan,

  My Xanterex XW when I set it up for AGM batteries - it sets the charging level - I do not have control over what voltage it charges at.  I assume that it takes into consideration the battery bank type and size, but am not really sure.
 

If you're not really sure, thankfully there is an easy way for you to find out.
 
I have a Xantrex XW6048 and it requires that you enter the size of your battery in amp hours.  Go to the same screen on which you told it that you have AGM batteries.  The next line down is the battery bank size.  The default setting is 440 amp hours, so if your battery bank size is different from the default setting, you should definitely enter the correct  data for your particular battery bank.  If you have a series-parallel arrangement of your batteries, be sure you calculate the amp hours correctly.  Four 12 volt 200 amp hour batteries hooked up in series still have a capacity of 200 amp hours, but it is 200 amp hours at 48 volts, not twelve volts.  Two 12 volt 200 amp hour batteries hooked up in parallel have 400 amp hours capacity.

You said your Xantrex selects the charging voltage.  I wouldn't let it do that if I were you.  You can manually enter the Absorb and Float voltages by going to the Custom Battery Menu.  This data varies from one battery manufacturer to another, so why use some generic, one-size-fits-all value.  Get a data sheet from your battery manufacturer, and use his recommendations.  Then simply enter those values under the Custom Battery Menu.  My batteries are Deka Model 8A8D 245 amp hours @ 12 volts and I have eight of them.  The recommended float and absorb voltages are available on the Internet.

Hope this helps.

poco

[ChrisOlson]

So which nominal voltage do you have on the house side?

48 volt on the house.  But I'm testing my new 24 volt turbine on the short tower by the house, hooked to two batteries, so I can get the bugs out of the new machine.  That short tower is the easiest one to raise and lower and it makes the job a lot easier.

Otherwise I got 12 volt in my shop office and 12 volt at the lake.  When I get my new turbine figured out I'm going to put my shop office on 24 volt and my 8 footer is going to be retired.  That 8 footer is flying on a chunk of 10" auger tube bolted to an old grain bin pad and I have to scale the tube to put a different turbine on it and hoist everything to the top with a rope and assemble it up there.  Not exactly one of my favorite things to do.
--
Chris

[fabricator]

We had a thunderstorm roll through in front of the cold front this afternoon, the wind got to around 16-18mph and my tail was coming off my bump stops, it looks like the furling might work.

[tecker]

Looks good the blade set is in there .  The electronics are a matter of one step at a time .Purchase more battery than you need and that will give you some fudge factor as you get it tuned up  .Down the pole to a disconnect and let it teach you . Watch the wire and use the lights as a running Amp gauge ( very good Idea). Ole doc wattson is a lair .There's know way it covers 100 amps or 50 amp continuous One look at the wire will tell you  that . One per phase might be oK .Looks like if you could get it up in the air 10 feet you could live with a guyed local set up until you get the interconnects worked out . If you don't need the power just yet you might pop for a Grid tied inverter and send it up the pole .The grind is the cols bucking as the current  shifts into your load and meets the next magnet . That magnet is the same polarity as coil in conduction.  I love to watch these things come together in this setting with wide open possibilities .don't be stingy with the posts .

[fabricator]

I had it running in 15-18 mph winds this afternoon, at 18mph it will go to maybe 3/8 furled, which seems pretty good to me for now, i really can't find any other problems, the balance seems really good, the tracking is within 1/8 of an inch, with the top bearing and the delrin yaw bearings I was a little afraid it might hunt to much but that doesn't seem to be much of a problem either, my only problem is right now even with four headlights on I can't run it long before the batteries are pushing the 56-57 volts, now I gotta get some wire in the ground and buy a couple morningstars and an inverter and more batteries....................................................

[TomW]

now I gotta get some wire in the ground and buy a couple morningstars and an inverter and more batteries....................................................

fab;

Well, I think you were warned early on it is a desease with no known cure. An addiction if you will.

Now you know

I started with a small glass PV panel for a few bucks off feebay now we must have a solid 10 grand in our system or more. I don't tally it up as it would seem ludicrous as a total number of greenbacks.

Still cheaper than many hobbies like a bass boat a big RV or that chopped and channeled American Iron coupe I would like. I won't even mention the early Harley. trike

Tom

[fabricator]

I will never even consider figuring out any kind of payback or return on investment, I really don't care if this costs more than buying power from the grid, it's way more important to me than any of that, l have a buddy who is kind of a survivalist type, he has a favorite saying I really like, "When the music stops, I aint gonna be the guy without a chair." There is a little of that involved but mostly, it's the fact that we are using something that blows over us all and has always been there and will always be there until this rock is incinerated by the sun, and we are using it to support a modern lifestyle. And, we are all doing our own microscopic part to stick it in the eye of big oil and king coal, yada, yada, yada, don't go gettin all teary eyed on me now guys.

[DamonHD]

Already weeping... Stop it...

[fabricator]

Sorry.

[defed]

Fab...you have 4 batts, wired 48v...is each light 12v and wired to an individual battery?  was no closeups of it, so i couldn't quite tell if that's what you had done.

[fabricator]

Yep each light is wired individually to one battery, this was Chris Olsons idea.

[freejuice]

I had it running in 15-18 mph winds this afternoon, at 18mph it will go to maybe 3/8 furled, which seems pretty good to me for now, i really can't find any other problems, the balance seems really good, the tracking is within 1/8 of an inch, with the top bearing and the delrin yaw bearings I was a little afraid it might hunt to much but that doesn't seem to be much of a problem either, my only problem is right now even with four headlights on I can't run it long before the batteries are pushing the 56-57 volts, now I gotta get some wire in the ground and buy a couple morningstars and an inverter and more batteries....................................................

Hi Dale,
I have about 12 inches of forward and side offset....since your tail furled that much in an 18 mph wind, how large your surface area is for your tail?
 I would like to know because with my forward and side offset, I would like to remember your tail size area when I evaluate how mine is reacting to the wind....trying to keep the second guessing to a minimum
 Thanks Gavin

[dlenox]

Dale,

In order to relly tell if the turbine is furling properly, I'm pretty sure that you may need to put a proper load on the turbine.

Just simple connection to batteries/lights may not really simulate a load, it's a good start, but things will change.

Glad to see that you are having fun, and never stop learning...

Dan Lenox

[fabricator]

I had it running in 15-18 mph winds this afternoon, at 18mph it will go to maybe 3/8 furled, which seems pretty good to me for now, i really can't find any other problems, the balance seems really good, the tracking is within 1/8 of an inch, with the top bearing and the delrin yaw bearings I was a little afraid it might hunt to much but that doesn't seem to be much of a problem either, my only problem is right now even with four headlights on I can't run it long before the batteries are pushing the 56-57 volts, now I gotta get some wire in the ground and buy a couple morningstars and an inverter and more batteries....................................................

Hi Dale,
I have about 12 inches of forward and side offset....since your tail furled that much in an 18 mph wind, how large your surface area is for your tail?
 I would like to know because with my forward and side offset, I would like to remember your tail size area when I evaluate how mine is reacting to the wind....trying to keep the second guessing to a minimum
 Thanks Gavin

It is 42 inches front to back and 48 inches tall, I believe with the front and back V cuts I figured it was 13 square feet.

[fabricator]

Dale,

In order to relly tell if the turbine is furling properly, I'm pretty sure that you may need to put a proper load on the turbine.

Just simple connection to batteries/lights may not really simulate a load, it's a good start, but things will change.

Glad to see that you are having fun, and never stop learning...

Dan Lenox

Oh I have no doubt of that, I always kind of expect everything to go the hell in a hand basket at any moment, that way you won't be disappointed  if it does, or, pleasantly surprised when it doesn't.

[tecker]

Those batts are brand new they will have to dischage really low ( maybe 12 volts) to get the chage factor to normal but you have some charging power. You can distribute your load and watch hold the amperage down to match the stator wire.

[fabricator]

OK, I have another question, say I want to measure the ac volts at the rectifier, I set my DMM to AC volts and probe two lugs and get say, 30 volts, how do I know what all three phases are putting out? Divide the 30 by two and multiply by 3?

[TomW]

. And, we are all doing our own microscopic part to stick it in the eye of big oil and king coal, yada, yada, yada, don't go gettin all teary eyed on me now guys.

fab;

I like to think of it as being part of the solution rather than just another part of the problem.

I cannot fix the worlds addiction to petroleum but I can work on my little part of it.

I guess I am in the same league as your buddy not wanting to be without a chair when, not if the music stops!

Just another old hippy with a red neck that hid under his hair til he went skinhead

Tom

[defed]

i was considering doing that as a test load on my 24v bank (2 bulbs, one each battery), but was wondering what happens if one light should fail (either go bad or loose connection) and drains the individual batteries at different rates.  am i right in thinking that if that happened, it would drain 1 battery to, for example, 12v while the other remains at 13v since nothing is running off of it?

[fabricator]

. And, we are all doing our own microscopic part to stick it in the eye of big oil and king coal, yada, yada, yada, don't go gettin all teary eyed on me now guys.

fab;

I like to think of it as being part of the solution rather than just another part of the problem.

I cannot fix the worlds addiction to petroleum but I can work on my little part of it.

I guess I am in the same league as your buddy not wanting to be without a chair when, not if the music stops!

Just another old hippy with a red neck that hid under his hair til he went skinhead

Tom

LOL, True dat.

[fabricator]

i was considering doing that as a test load on my 24v bank (2 bulbs, one each battery), but was wondering what happens if one light should fail (either go bad or loose connection) and drains the individual batteries at different rates.  am i right in thinking that if that happened, it would drain 1 battery to, for example, 12v while the other remains at 13v since nothing is running off of it?

I'm really just running mine for several hours at a time as more or less a shake down period, I bought four new headlights, they are single element, the type used in older chevy trucks, they generally can be expected to burn for several thousand hours, but yeah, I suppose if one did burn out that battery would get over charged, but right now I'm in pretty close attendance of the thing when it's running.

[dlenox]

Dale,

OK, I have another question, say I want to measure the ac volts at the rectifier, I set my DMM to AC volts and probe two lugs and get say, 30 volts, how do I know what all three phases are putting out? Divide the 30 by two and multiply by 3?

Typically when building stator if you have the single phase output of star/wye stator you multiply by 1.73 to get the total volts, so the converse would be true that if you have total output voltage / 1.73 should give you single phase volts.

BTW: how did you wire your stator?  wire size/# turns/etc?  Last stator that I made for my 17' (did not pour resin yet) I was able to squeeze in three in hand #15 coils.  They were big - but got them to fit!!!

Dan

[defed]

OK, I have another question, say I want to measure the ac volts at the rectifier, I set my DMM to AC volts and probe two lugs and get say, 30 volts, how do I know what all three phases are putting out? Divide the 30 by two and multiply by 3?

i just looked this up the other day, not sure if i have it right, but i think it's:  AC from two leads x 1,4 gives the AC, then subtract 1.4v for the rectifier loss to get the DC output.

[fabricator]

Dale,

OK, I have another question, say I want to measure the ac volts at the rectifier, I set my DMM to AC volts and probe two lugs and get say, 30 volts, how do I know what all three phases are putting out? Divide the 30 by two and multiply by 3?

Typically when building stator if you have the single phase output of star/wye stator you multiply by 1.73 to get the total volts, so the converse would be true that if you have total output voltage / 1.73 should give you single phase volts.

BTW: how did you wire your stator?  wire size/# turns/etc?  Last stator that I made for my 17' (did not pour resin yet) I was able to squeeze in three in hand #15 coils.  They were big - but got them to fit!!!

Dan

My stator was wired as per the Dans seventeen footer, 14ga two in hand, ummmmm 59 turns I think.

[wooferhound]

Yes . . . for many of us cost is not a major consideration
here is a Poll asking
Why do you want Renewable Energy ?
http://fieldlines.com/board/index.php/topic,141180.0.html

[Flux]

OK, I have another question, say I want to measure the ac volts at the rectifier, I set my DMM to AC volts and probe two lugs and get say, 30 volts, how do I know what all three phases are putting out? Divide the 30 by two and multiply by 3?

I hope this quote thing works and this turns up in the right place.

This question is a confusing one to put it mildly and really is not much use but I will try to answer it.

For a sine wave input to a 3p phase bridge rectifier into a resistive load the dc voltage will be 1.4 times the ac volts. This works for a turbine up to cut in.

Beyond cut in when you are supplying current into the battery it becomes absolute nonsense. When conducting into the battery the ac input waveform is a clipped something or other with a peak value of the battery volts plus a couple of diode drops although you can forget the diode drops as far as this goes.

No multimeter, average reading or rms will give you any figures that you can make any use of, the assumption that it is a sine wave no longer applies.

If you have enough wind and you clip hard enough then you may be able to assume that it is virtually a square wave input, you can calculate and even measure the peak, mean and rms of this  but I still maintain that you will be no wiser.

What you will find is that starting with very low wind you will get a rising ac voltage up to cut in and at this point the ac will be the dc battery voltage divided by 1.4.  It will more or less clamp at this value as the wind picks up but it will change with the change in waveform and it will depend on what your meter reads how much it rises but even so the thing is nonsense. If you have a heating load or some other loading that doesn't clamp the alternator peak voltage then it will make sense but f0r battery charging forget it.

Perhaps the only thing you can expect is that all 3 ac voltages will be the same, if not you have a fault somewhere
Flux

[SparWeb]

Hi Fabricator,

If you want to dump more load than just a few lights, try ripping the heating element out of a discarded clothes dryer - they are (sadly) very easy to find at the dump, by the side of the road, behind shopping malls....  Cut the element wire into 3-4 even pieces, hook them up in parallel, and you'll probably be able to dump 30-40 amps with it.

And about testing the AC with a multi-meter, most meters won't give you a correct reading.  I assume you mean you're reading the AC across the lines while it's charging the battery set.  I learned the hard way that these things tell lies if the AC wave is not a perfect sine.  If the thing just reads the peaks, divides by 1.41, and spits out a number on the screen, then you are definitely not getting the right answer.  If you are using a "true RMS" meter it might be closer, but there are spikes and noise that it may pick up and exaggerate one way or another.  Sorry not actually knowledgeable about it - just know enough to be critical.

It's just a circuit simulator - but it does illustrate the waveform when charging batteries:



The DMM would be picking up the yellow line.  It's hardly a sine.  Lots of scratchy stuff on the up and down ramps.  Flat on top.  The RMS is 24V or so.  A multimeter might call it 18V or 19V.

Oops  It seems Flux beat me to it.

[fabricator]

Flux, you have to remember that I don't know enough about this stuff to know what is nonsense and what isn't, I guess
I must be asking the wrong question, if there is no place you can measure anything that is coming off the alternator how can you know anything about performance?
Steven, thanks that helps some, but I still don't understand how to quantify what the system is doing, is the main measurement simply battery voltage?

[ghurd]

It is that simple-
Charging Amps and at What battery voltage.

Wind speed too, but it's not overly accurate under different conditions and directions (IMHO), so don't get too confused if yesterday's and today's numbers don't jive as close as you think they should.
G-

[TomW]

is the main measurement simply battery voltage?

fab;

I would say, in battery charging applications that the 2 things that define performance are amps into the battery and voltage at the battery.

This gives you watts into the batteries (Volts times Amps). And is where the rubber meets the road in battery charging, in my humble opinion.

Beyond that I guess you could compare input energy to output energy with a pile of equipment?

Maybe I don't understand the question?

Tom

[fabricator]

Well I guess it is that simple, two almost identicle replies by resident eggheads, battery voltage and amps into the battery, QED.

[Fused]

I guess Im confused. I have in the past tested my 3 phases by using the star connection and the leg of each phase. Compare the 3. I thought it was ac output per phase times 1.4.

I m probably way out of line.

Good luck Fab, great looking mill there.

Fused