Advice on motor

[leon4224]

Hi I got this motor and Im going to make blades for it from pvc. I just wanted to know if this is good motor and how much can I get out of it and if I should make 6 blade or 3 blade? I live in cold and windy area. Will this motor over heat and burn on hi winds ?
Permanent Magnet DC Motor by GS Electric.
Has a 6" heavy pully for mounting your blades securely.
I put my volt meter on it and gave the pully a spin. Easily got 9VDC
130VDC,  2.75 HP, 21AMPS, 6400RPM
Generate Over 2700 Watts of FREE Energy

[tanner0441]

Hi

First 3 blades are better than 6.

At 6400 RPM you are looking at 50RPM per volt. So assuming a 12V system 590 RPM to just equal the battery voltage, with PVC blades that is optimistic because to make around 14V to get anything at all going into the battery your going to need 700 RPM plus.  Also allow 0.6 of a volt drop across your blocking diode I doubt you will ever see more than a few watts with a direct drive plastic blade set.

A 6in pulley, remove the bit in the middle for the shaft, and your only going to have 2 to 2.5 ins to mount your blades on, if it does get up to any speed I would not want to be near it if it yaws.

I would recommend reading back through posts on here and look at geared drives and wooden blades.

Brian

[leon4224]

what if I buy 3 good blades and hook up my solar 120 watt panel will I be able to charge 12v battery's? Lets say 4 100amp 12v deep cycled empty battery's will it charge them in 3 days if I got wind and sun? Approximately is it possible to figure it out? 

[tanner0441]

That depends to some extent on the state of charge of your batteries, if you continue to drain them, the design of your blades, how stable your wind is re turbulence etc, and you haven't said what your measured wind speed is. "I have good wind", is very little use, I have wind that can take you off your feet but it will not keep my 200W turbine feeding the batteries.

You really need to read a lot of the threads on here use the search to look for specific topics, beg borrow or buy the books advertised on here, and you will, if you can't answer your own questions, know the questions to ask.  There are plenty of thread on blade design, and how to make them.

I see your in the UK, which area?

Brian

[leon4224]

I think I will get more than a few watts with a direct drive plastic blade set. I'm in MN USA up north very windy. If you have wind that can take you off your feet but it will not keep your 200W turbine feeding the batteries then maybe you need more powerful wind mill ;-)

[birdhouse]

I think I will get more than a few watts with a direct drive plastic blade set

maybe...  maybe not.  ~560rpm for cut in is pretty darn high! 

i think you might be better off searching for a new motor. 

my 8.5' mill cuts in around 240rpm, and seems to "match the load" so to speak pretty darn well even as the winds pick up.   

also, PVC blades aren't very "performance oriented", so that part alone is going to make it a losing battle when high revs are needed just to get a few watts. 

just my thoughts. 

adam

[leon4224]

I was just spinning it by hand I got good voltage. I can imaging this thing go on hi wind. My concern is now if is not going to burn out because of spinning that fast.. pvc blades can be good if made correctly. I'm in the learning process and don't believe any one who say is crap till I try it. Many professionals told me this cannot be done before on other things but I did it anyway and I worked. I don't believe this powerful 2.75 HP, 21AMPS, 6400RPM motor can't charge my 12v battery on fast winds. I will maybe buy professional wind blades from ebay later but for now this free setup will do.

[birdhouse]

pvc blades can be good if made correctly

that's debatable...  PVC blades CAN perform well with a motor that is correctly matched to the dia, cut in ect. 

i don't doubt that the motor you have isn't a fairly beefy unit, just has a really high rpm rating that isn't so good for wind. 

i'd be willing to bet that a nice carved 2 blader out of a choice piece of 2x4 would outperform a pvc 3-blade set up with that motor. 

if your bent (pun intended) on pvc, try it and let us know.  i'll bet the same effort could go into a wooden set that *might* work with that motor.  560rpm is still mighty high to get to a trickle charging scenario.  this means you'll have to hit 580-600 rpm to really push any amps out of that motor. 

best of luck, and keep us posted on results! 

adam

[birdhouse]

one more bit, here's some footage of my 8.5' mill pushing good amps (300w or so).  i know for a fact that machine is running under 560rpm during the entire video...  just to give you an idea... 

http://www.youtube.com/user/boschme?feature=mhee

[tanner0441]

Hi

I will try to explain. Because the wind at my place can blow you about doesn't mean it is good wind. There is a lot of turbulence from trees and buildings. I have seen on a couple of occasions my turbine putting double its rated output but it spends a lot of time spinning below cut in while thrashing about on the yaw bearing.

You still haven't told us what your measured wind speed is.  What height mast or tower are you planning on? All these things play a big part on things. If you intend to go down the plastic blade set what diameter are you looking at.

Wattage is the product of amps times voltage, so perhaps at 6400RPM your motor could produce over 2Kw that is at 130 V your talking 12V.   2Kw at 12V is best part of 170A your windings are rated at 21A 12 times 21 is 252W. I will put money on the fact you ain't never going to see anywhere near that with plastic blades. My unit has 6ft 6in blades to do 200W. each blade is just over 3ft long.  A 3ft plastic blade anchored on just the first 2in is not going to last long. The blades don't just spin round the shaft the tail keeps the thing pointed into the wind, any turbulence or change in wind direction will twist the blades to destruction.

It was suggested you make a good set of twin blades, two blades will spin faster than three but are more prone to gyroscopic forces when the thing yaws.

You can get 9V spinning it by hand. Fit a blocking diode and connect it to a battery and spin it by hand.


Brian.

[Flux]

If you are in a good wind area then you should get results with a fast 6ft  ( preferably 2 blade)prop and it should cut in below 12mph.

Not having seen the motor shaft I don't know if it will support a 6ft wooden blade prop when yawing.

If you must go down the pvc blade route then about 4ft maximum diameter and aim for cut in above 15mph.

All round I suspect a decent 5ft 3 blade fast wooden prop would be a good compromise. Not sure what commercial blades you are looking at but the only thing that would work sensibly is someting other than those bent tin things that are advertised everywhere.

If you have high winds and a decent prop you may need some form of power limiting ( furling) in winds above 30 mph.

Flux

[leon4224]

My winds more then 30 mph

[tanner0441]

How have you arrived at your wind speed? A mean wind speed of 30MPH seems high.

I have a similar 240V motor under my bench it is rated at 2000 RPM. The pulley is strong enough to take a blade set, though the motor shaft is a bit thin, but to get the speed your going to need, I would still look at a wooden twin blade set. Have you sorted the tail and yaw set up yet? Or the mast?

Brian

[leon4224]

I don't know my wind speed but is in the farm up north open spaces good wind and I will mount it on 15foot metal poll. I don't want to make wood blade because I'm think they will brake. In winter here I got crazy winds. The wind took my other trailers home metal roof off last winter that's how strong the winds here. Thatch why I worry motor get to hot and burn. I don't know how to slow it down. PVC is very thick and I think they can handle it. How long do you think the blades should be?

[tanner0441]

Read back in this thread, you have been advised no more than 4ft Dia.  I can't see the motor producing enough power to burn up, to prevent the thing over speeding look at the designs for the tail assemblies.  The wind will see the blades as a disc, and with the yaw bearing off set if the tail is done right the blades will swing to the side.

A decent set of wooden blades will outlast, and out perform PVC blades in all aspects, strength, performance, everything.  A good set of wooden blades will turn faster than the wind speed if the TSR is correct, PVC blades are drag blades, they cant spin as fast, and in cold weather will en-brittle and shatter in the cold, and the bits can hurt or injure anyone they hit, and if your tail is not designed right the blades will never be able to turn out of the wind to prevent over speeding.

A 15ft pole is way too low and will be subject to all sorts of turbulence. Are there any trees or buildings around the site you propose? I still think you should set up an anemometer and measure your real wind speed.

 To build your turbine, all the information is on this site. Things like how to arrive at the offset, how to mount the tail boom, how to set up the yaw bearing, the size wire to use to connect to the batteries.  Once you have the power what do you intend to do with it?

Brian

[leon4224]

can you please point me to the page on this forum where it shows how to make wood blades I just cant find it. For now I will use power for little things like laptop, lights, 55in Tv if it don't burn out because I don't have new pure sound wave inverter I just have 2500 inverter old one. If I can run my 220 well pump or water heater off this someday that would be good. I'm exchanging my old Murray grass lawn mover for new 700watt wind generator in box with controller. So I will have 1 120watt solar panel, 1 wind generator 48v made in china and 1 that I'm making. I will put everything together. Next step is to get cheap used deep cycled battery's as many as I can. I got 3 now but I think cold killed them standing in my garage for year. I don't think they hold charge anymore. I was charging them but that didn't help. How many 12v 100 amp battery's do you think I need for system like that?

[birdhouse]

lots of good info here:

http://www.scoraigwind.com/pirate%20oldies/Hugh%20Piggott%20PMG%20May-October%202002.pdf

[ghurd]

It is just a typical treadmill motor.
Search the site for info related to treadmill motors.
Sorry to tell you this but it is not a great motor for wind.

Might start with reading this,
http://www.fieldlines.com/index.php/topic,143574.0.html

I have (or had) one just like it.  It is not very heavy duty in my opinion.
G-

[tanner0441]

Hi

Two points.,

1 Remove your water heater from the equation completely.

2 Old batteries are never a good way to go. Ideally you decide on the voltage you are going for and buy all the batteries in one go, also you have 120W of solar, and an unknown amount of wind, so if you have too many batteries you are not going to charge them. 

Near the start of this you mentioned your system was going to be 12V now your talking about 48V. You need to sit down and plan just what you are going to do.  If you go 48V your solar panel is redundant, and don't expect to see 700W out of the wind generator for days on end.  A 2500W inverter at 12V is over 200A and is going to want some heavy cables from the battery.

I would suggest you buy the wind power book from this site and sit down and read it.

Brian.

[ghurd]

Might want to look at this long post about a treadmill motor,
http://www.fieldlines.com/index.php/topic,140404.html
G-

[Harold in CR]

 My 2 cents is, I played with a much more robust treadmill motor, and mounted the blades directly on the flywheel.

 BE AWARE, the threads on the shaft are LEFT handed, so the flywheel doesn't unscrew when the motor is running under normal use. The brushes in mine must be slightly advanced, because, the output fell to near nothing. I pulled the motor apart, and found the brushes all chewed up, from spinning BACKWARDS, because of the left hand threads.

 Be sure you know what you are doing, before mounting the blades-hub.

 I have successfully built a 4KW alternator-gear box driven, wind turbine, so, I know what I am doing.

[leon4224]

Yea I think I'm going to go with propane for water heater. Old battery's that I get are cheap and hold good charge depends what you get. Some times you can get almost new deep cycle battery for $30. Some times $20. I'm being economical and will make it work with what I have. V48 is on the new wind turbine that I will get soon. I might make 2 systems if I have to 1 48v 1 12v. My inverter got heavy cables. I don't need book because all is going to tell you is to buy buy the American way. I will make it working with what I have and maybe buy some cheap things on the way.  Can I use some gear with belt to increase my speed on motor so it spins very fast?

[leon4224]

This is how I'm going to increase the speed of the motor
Pillow Blocks, Shaft, & Shaft Collars

[birdhouse]

OH GOD leon...  i don't quite know what to say this without sounding like a complete as$hole. 

i could just say you're doing it all wrong...  but then i don't really know what your goals are.  if less than 100w is your goal with a mill that might last a year at best, with constant fiddling, and dangerous, then maybe you made the right decision.  but if that's the case, just buy a safe 100W solar panel for $120 and keep your safety. 

HOWEVER:  FYI:  threaded pipe/couplers are very thin at the thread cut and dangerous.  there are folks here that have been marred by them breaking. 

if you put half the money/effort into finding a "good" motor, you'd be way further ahead.  it my not be flying yet, but at least you'd have a powerhouse we could guide you into making into a safe and powerful build. 

because all is going to tell you is to buy buy the American way

we are not about buying the american way.  we are about producing the cheapest, safest, most reliable watts possible from the wind. 

when i joined this forum i didn't know hardly anything about producing watts from the wind, but, i LISTENED!  i asked about air-403's, and various motors, and i finally sought out a good three phase stepper motor.  it produces, and produces well, and is very robust and safe. 

gearing is something rarely accomplished well.  chris o has done it, so has hugh(the father of wind power so to speak), yet he abandoned the idea years ago due to complexity and stength (read safety)

poorly done gearing is bound to end in disaster.  HVAC parts are not up to the task. 

just my thoughts without trying to sound like a total as$hole

respectfully
adam

[leon4224]

Buying the American way is suggestions like :Get the good motor pay good money for it treadmill motor wont do it, Get good blades because PVC is cheap and danger oh no, get good expensive battery's 2 of kind, go pay money to professional. I have seen people do it on YouTube for example and it last long time.. It will give me allot more power then just 100w solar panel. If PVC brakes it is easily replaceable and if you get good q PVC it wont brake that easy. I'm on the farm and if the blade brakes far away behind some barn big deal. Don't forget I didn't pay for the most parts to build this is almost free. I don't know what you meant by saying end in disaster. You have to start somewhere like child.. make something first know how it works and then buy professional one if you like. I can use parts from the car don't tell me they will brake like toy. Not every one have money you know to buy all this staff... some of us making it from 0. Gearing is something not something that rarely accomplished well if done correctly. The father of wind power probably just got big$ and don't want to bother with gearing and remembered safety reasons.

[birdhouse]

your response is kinda hard to follow.  but i understand your point. 

there will be a time where you'll want more power from the wind, and i'm guessing you'll ask more questions then. 

i still stand behind my idea of carving a fast (tsr7+) two blader out of a clear 2x4.  probably wouldn't have needed gearing for that... 

adam

[leon4224]

Carving blades from wood ? I would really cry if my blades brake ;-) I will try it ;-) very time consuming I guess.
http://v8nu74s71s31g374r7ssn017uloss3c1vr3s.unbf.ca/~scott/BladeCarving.html

[birdhouse]

in a second reply, after re-reading,

your not understanding or at least recognizing much of the post. 

Get good blades because PVC is cheap and danger oh no

wood blades are way faster, create way better lift, and are way stronger than pvc, as others have posted.  if you have heaps of pvc on your farm, you probably have some good wood laying around as well. 

do you even understand "tip speed ratio"?  might be time to do a bit of reading. 

adam

[birdhouse]

you can do it with a chainsaw!!!!  courtesy oztules...edit: not oztules video, but mine...

http://www.youtube.com/watch?v=aNQ_SW1Njf4&list=UUabajWb3cDP2fzWZCO4x2Bw&index=10&feature=plcp

[leon4224]

cant see this dude with chain saw holding with his hands like that on saw and chain come off ... Holding chain saw like that now that's unsafe.. Some one was scaring me that pvc blades unsafe ;-) I understand that wood blades like that faster better but they are allot more complex to make. They have to be perfect. I have very big PVC pipe very thick heavy duty not the home depot staff.. I will try that first.

[Frank S]

Leon; I'm not going to start trying to say things must be done this way or that way for the simple reason the last wind generator that I built was 30 years ago as an experiment to see if I could make a 9 phase generator and a 9 phase motor.
 And yes it did work all be-it not to full power because of the Chrysler alt that I used
 Be that as it may I do have a couple of comments actually concerns.
 without having the tail mounted so it can furl in high speed winds thus preventing the turbine from spooling up like a turbo charger with no load on it would be one concern since  you can find numerous reports of turbines reaching 1000s or RPMs then going off into never, never land.
 My second concern is as was mentioned the threaded flange mounting for the unit. Now I know it is difficult to find a correct size tubing or pipe to fit inside of the one you already have mounted but for safety and extra strength if you could insert a tight fitting tube inside of the existing mounting pipe then have it come up through the rectangular tubing frame and attach it to the top surface this would negate much of the stress on the threads of the flange and the pipe. Also help to prevent it from unscrewing
 I believe that I am the one who suggested using the shaft bearings to mount the blades I see nothing wrong with this per say as this is the best way to prevent damage to the motor shaft.
 Set collars are good as far as they go. even better if you drilled into the shaft just enough for the set screw to have a locking seat indention locator, however a tubing sleeve between the blade mount and the forward pillow block would prevent any possible thrust movement
 There is nothing wrong with belt drives for reduction the alt or generators on cars and trucks have been powered this way for over 100 years and machines have been powered by belts for 200 years
 Some belt designs are better than others only because they reduce the loading on the shafts 
SO my 2 concerns would be the furling and the mount the rest is what it is for the size.
 Plastic blades can have a laminated support added to the mounting area to increase the strength if needed 
Yes maybe wood blades are faster maybe not maybe they are stronger maybe not
 Can you get a better TSR with the wood blades? sure for the simple reason that you can fine tune the up stream and down stream angle of the air foil where as with the PVC blades made from pipe this is a lot more difficult however even that is somewhat adjustable if the PVC is thick enough.
 Direct mounting blades on a motor with only a 100 or less shaft diameter would sound ludicrous to me that was my only reason for suggesting the jack shaft set up in the first place.
 if you had facilities to machine out a hub that would have its own bearings to mount the blades on then just plug in the motor with a coupling or if you wanted to do what you did and couple the motor directly to the back end of the shaft again with a coupling that would be doable as well
 What you have is a good starter as everyone needs a place to start from.
 By this time next year you may be building a copy of a Bergy who knows. or you may chose to cobble a piece of plywood into a couple of stators with a dozen tear drop coils and a 13" disc brake rotor with 20 magnets on it again who knows.
  I won't ever say that I would not build an axial machine using the home-brew methods because I know for a stone cold fact that 1000s have been built and some have been operating for many years producing electricity
 I am currently exploring designs of over 100 different types of generators ranging from a few watts to over 100KW and even possibly into the half a megawatt range does that mean that I'm going to actually construct any or all of them? there is a good possibility that within a year I will settle on 4 designs to build ranging in a degree of difficulty from a simple   5 watt servo motor out of an old printer to a 40 pole generator with 500 lbs of copper in it producing true 3 phase @ up to 600v Ac   

[tanner0441]

Take the time and read back through this thread from the beginning. Plastic blades will never outperform wood blades in performance, or strength.  Unless you choose wood that's full of knots and splits.  Wood blades are lift blades that can actually turn faster than the wind speed. Plastic blades are drag blades and have a finite performance figure lower than the wind speed, and can be very noisy.

Wood blades will flex and twist in the wind and will offer a progressive resistance to bending across a wide temperature range. Plastic blades will bend so far then crease and break, or if they are cold enough shatter. I know I have had it happen on me.

Follow the instructions on here and it doesn't take that long to rough a set of blades out. The finishing and balancing can take some time, but you have to balance plastic blades.  If your not prepared to spend the time balancing your blades, whatever the material your going to shake the front bearing out of your motor.  DO NOT do what I tried when I was starting and hold onto the motor with a set of blades on and point it into the wind to test the blades, it is surprising how fast a set of blades will spin up with no load on the turbine.

There are several people on here telling you to read up on things, perhaps it's time to listen to them.

Brian.

[ghurd]

I'm on the farm and if the blade brakes far away behind some barn big deal.

When a PVC blade breaks, it will be in high winds.
The imbalance can make the turbine jump off the tower,
or bend the shaft,
or...
I think PVC is fine for small stuff, but it gets past small when the gearing is added.

I understand that wood blades ... They have to be perfect.

No, not perfect.
Just sort of close to each other at each point.

On your side with a couple things...
- PVC can be 4~5 TSR.  And they are not loud if done right.
- Cheap is good.  In fact, cheap is my favorite.
G-