classic 250 turbine input

[ldiorio]

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

[russ_drinkwater]

A good question. Anyone??

[TomW]

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

[dgd]

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

[ldiorio]

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

[dgd]

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

[ldiorio]

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

[dgd]

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

[ldiorio]

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

[ClassicCrazy]

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

[kitestrings]

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

[ldiorio]

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

[russ_drinkwater]

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!

[krementz]

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.

[russ_drinkwater]

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.