have a Classic 250 that i installed with a 48v wind turbine with a 48v battery bank.
having trouble getting my turbine up and running-doing some trouble shooting
have noticed that with my turbine not spinning the input voltage at the classic varys from approx 35 to 43 volts
have been told that thats a % backfeed from the battery bank
so if i get 50-60 volts when the turbine is spinning does that mean that the turbine is only outputting approx 20 volts???
do i need a blocking diode to stop the backfeed so i can see a realistic turbine output
tks
lou
A good question. Anyone?????????????????????????????????????????
Not sure it is related but a solar Classic shows something like 3/4 battery volts on its input in the dark or disconnected.
Been there, done that. Got the T-shirt.
Be aware you are taking a chance with no clipper on the turbine Topped off batteries with high winds pretty sure the classic will let the turbine freewheel, possibly to destruction with no clipper.
Just in case you were unaware you "need" a clipper.
Tom
Quote from: ldiorio on April 26, 2017, 04:36:50 PM
so if i get 50-60 volts when the turbine is spinning does that mean that the turbine is only outputting approx 20 volts???
do i need a blocking diode to stop the backfeed so i can see a realistic turbine output
No. There is no effective backfeed. The Classic simply holds its input terminals to a voltage that is a proportion of the battery voltage when there is no input to the Classic.
When input is detected that allows current to flow then its only the power from the turbine that comes into the Classic.
As TomW says its a risk running a turbine straight into the Classic because in high winds with a fully charged battery the Classic will stop sending power to the battery (to prevent overcharging). This will allow the turbine to free spin and unless it has an effective mechanical or electrical braking, it will probably spin to destruction.
Do some research and read about the Midnite Clipper.
dgd
thanks
so if i get 50-60 volts on the classic input thta would be 100% input from the turbine--my prop voltage is about 37volts
thanks again for the clarity
i think i have a problem with the turbine bec i get up to 55 volts but no assoc amps --if the volts go above 60 i get spikes in the amps--have tried various charging cruves but of no help-might have to get another turbine and run then both to get more voltage above the 48-55 battery voltage
--if i was getting significant amps i would add a dump load
thanks very much--still learning
What is the make and model of your turbine? and its rated power output?
A 48v DC rated turbine will not generally make useful power until its output voltage is well above 48volts, the faster it spins then the high the voltage.
Most turbines have 3 phase AC output and convert to DC output using a 3phase rectifier. Is that what you have? Or do you have a turbine control box of some type that contains resistor and heatsinks and perhaps other electronics?
Or is there direct DC from the turbine?
A photo or three of your setup would be useful to see.
dgd
have a SC48VAC 3 phase AC Thermodyne with 7 blades on a 30' tower in the middle of a filed on a hilly area connected to a rectifier then thru a epanel then a classic 250 w/8 6 volt Fullriver batteries(AGM). turbine has a capacity of 1625 watts
its identified on there web site as a KT7 turbine
thanksPS -am thinking of getting a second turbine to double the voltage
ldiorio,
Ok, thanks for that info. Don't buy a second one of these turbines.
This turbine is AFAIK a copy or rebranded Missouri Wind and Solar (MWandS) alternator based turbine. These really require very high wind speed to generate any useable or useful power.
IMHO these are a complete and utter waste of time, money and wind.
Sorry to sound negative but I'd recommend you look for a non alternator based turbine. Lots on Ebay and Chinese make lots of reasonably priced and well designed wind turbines.
Maybe others here will have some suggestions.
dgd
hi what is your experience with your 2KW turbine
have no idea what to look for but know i want a 48V AC turbine
wish i could get some recommendations from you and /or others on this forum
thanks very much for your input helpls a lot
Lou
Quote from: ldiorio on April 27, 2017, 07:41:40 AM
hi what is your experience with your 2KW turbine
have no idea what to look for but know i want a 48V AC turbine
wish i could get some recommendations from you and /or others on this forum
thanks very much for your input helpls a lot
Lou
Lou - take a look at this book, also take a look at the Otherpower webpage
http://www.otherpower.com/otherpower-store
Here is some interesting history
http://www.otherpower.com/learningcurve.html
Larry
Hi Lou,
Sorry I'd missed this post. It looks like you got some good comments. We have a 15' home built axial-flux turbine on a pair of Classic 250's. It works well, but I agree that if you do get a suitable turbine that you will need a clipper or reliable method of shutting things down.
No one mentioned Bergey (XL1). There is a small, 1 kW Bergey that has been used on a CL250. If you google AltE or Kansas Wind power you should see some vendors; or try you-tube.
The 35V is normal. For a turbine to work well you really need a bit of 'headroom', or voltage above the nominal voltage of your bank. I think mine starts at about 59V.
Unfortunately some of these small turbines get sold with unrealistic expectations.
Good luck, ~ks
just saw your post
having a storm in new england and trying to modify the charge wind curve but to no avail--i get the voltage to gho above 60 with some wattage but i quicky drops back to zero--that has been my experience with the Thermodyne 48V turbine--they really should make a 60 volt turbine to give me some headroom lol--i was thinking of getting another turbine to doube the voltage but am not convinced that will solve the problem---
i think i should look at a diff brand ?????
Lou
Just had a look at the price of a clipper!
Errr, a lot of choking and gagging, lol.
Sorry, but for me it would into $2,000 plus landed here in australia!
Quote from: ldiorio on April 27, 2017, 05:29:51 AM
have a SC48VAC 3 phase AC Thermodyne with 7 blades on a 30' tower in the middle of a filed on a hilly area connected to a rectifier then thru a epanel then a classic 250 w/8 6 volt Fullriver batteries(AGM). turbine has a capacity of 1625 watts
its identified on there web site as a KT7 turbine
thanksPS -am thinking of getting a second turbine to double the voltage
Even if the turbine was reliable and the vendor honest, there is no way you are going to get any significant energy from a 30 foot tower. The rule of thumb is the bottom of the blades of a turbine should be 50 feet over any obstruction within 500 feet. That rotor is about 6 feet in diameter, so you are at only 27 feet over turbulent ground ("hilly area"). The turbulence and wind shear will kill most of the theoretical power.
Reading their website, I am sorry to report you have been scammed, unless you only wanted a kinetic sculpture.
That may be the science of it, but in reality wind turbines will work even with obstacles near them that create
turbulence and eddies. I have had 2 x 24 volt pma's running into a kung-fu grid-tie inverter and in our windy post winter times the turbines feed .5 - 1 kw per day back into the grid.
Now these turbines only have 2 foot of clearance from the roof of the shed where they were mounted.
Yes I admit it was far from perfect and looked like crap, but they produced power.
One now provides night time supplementary power to my eldest sons battery bank.
I would love to have it mounted on a 40 windmill tower, but finances are tight at this time.
I think the point is more that they advertise some of those wind generators as 2000 watt units but when you look at the chart they only put that much power out if the wind is blowing over 45 mph . Maybe about the same wind speed it would start self destructing if it was spinning that fast.
Larry
I take the specs data with a grain of salt.
But afterall they are pma's and not the space shuttle.
If it works for you and does the job required and is reliable then that is good enough for me. ;D
russ - I think you just proved my point: 0.5 to 1 kwh per day is about 10 cents. I get 5 cents a beer can for recycling.
1 kw a day is 44 cents for me.
I just rigged it together to see if it would work.
For grid tie power generation I agree, turbines of small size are a waste of cash!
A mate had 2 x 3 phase ones and a bucket full of problems for 6 months.
I got him a cheap grid tie inverter and some $50 a panel 2nd hand replacement panels and he has not looked back.
On the other hand where my sons house is the 24 volt pma puts in 1- 1.5 kw most nights which is a massive bonus
to their power usage on the stand alone system, considering they only use 3-5 kw a day.
Mate, I look at wind turbines like my kids, if I do not expect too much I am never disappointed! :o 8)