servo motor blades

[Bub73]

 I have a GE Fanuc 2000 rpm 9 amp 200 volt servo motor I would like to add to my 12 volt system.
My question to start with is what size blades/sweep area would be best for a 5 to 15+ mph wind area.
I'll have more questions further on I'm sure.

Thanks for any input
Bob

[97fishmt]

Hi Bob,

I have had good luck starting with an 8 footer
on different servo motors.

Considering your wind resource,  low wind.

If you had or get a little more wind  a 6 footer
would work real nice.

I carved 2 sets of 6 footers last month and both
work excellent on this one.


An 8 footer will over power that little motor if you get
big winds but if you are trying for the lower wind speeds
then it might work nicely.  Just build in furling and you'll be OK.

[97fishmt]

Hey Bob, I really should not advise an 8 footer for a 10 amp motor.

An 8 footer can get out of hand if you let it.  I would be comfortable
suggesting a 6 footer with a wide cord at the root to get it going in the
lite winds.  A 6 footer is pretty safe.  I just let em rip with no furling
and see if the motor can handle it.  30 amps is the most I see out of the
6 foot prop and different motor set ups.  Maybe they self govern although
I haven't put one up in clean wind yet.  I'm digging my 10 footer up on
the tower right now. 

I did score another tower last month I'll be fabricating a hinge base for it
soon and coming up with where to put it.  Furling is still the way to go if
you want it to last.  Have fun.

[birdhouse]

bob-
have you removed the brake yet?  i've got a fanuc motor close to being a mill.  had to remove the brake from it.  it's a bit tricky to do it without removing the magnets from the coils.  (i've heard that if you do this the servo can lose a lot of its power)

mine is a 2000rpm 140volt 20amp unit.  i decided on an 8.5 foot dia. three blade prop, though i haven't flown it yet. 

your will get a very low cut in rpm for a 12 volt system.  mine hit 12 volts at 120rpm on the bench, and yours is even a higher voltage, so you may hit battery charging voltage below 100rpm even. 

did you get that motor on e-bay for $4.25 + 35.00 shipping?  i meant to bid on that one and forgot to, but was astounded when it went for $4.25. 

i would think an eight footer would easily hit 100rpm and give you more constant power in lower winds, but if i put that large a prop on that motor, i would enact a furling system for sure.  (don't trust me though, i haven't finished my first mill yet)

let us know what you do!

adam

[Bub73]

Thanks guys for the input;
 My brother got the break put for me and it did come from e-bay but some more than $4,25 .
I'm going to try and get a photo and recheck the 12 volt cut in with a hand tach.
may be this evening if things go right.
 This will be a long project so post back as things come together.

 Thanks
Bob

[Bub73]

Sorry I mis posted the voltage in my first post.
It should have been GE Fanuc 2000 rpm 9 amp 165 volt not 200.





Bob

[birdhouse]

bob-
that's still a good motor!
err.. genny

adam