Whisper 900 wont spin in with direct wind

rodwood
rodwood Registered Users Posts: 5
Hello all, i have a question in regard to my whisper 900 it has always worked fine, recently I went to a straight grid tie no DC backup leaving my perfectly working wind generator to spin in the wind happily, I could not claim the produced power because I don't store batteries any longer,  fast forward a couple months and it very slowly spins as the wind is directly on it, I took it down and it spins freely with no resistance at all, I'm not sure what to do,

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    sounds like a short in one of the feed wires.    But leave it down, why wear out the bearings for no reason ?

    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • rodwood
    rodwood Registered Users Posts: 5
    I would like to give more info, first I'm not sure if the feed wire you mention is the 2 wires from the generator feeding the charge controller or if it is internally within the Gen, the 2 wires leaving the charge controller are open taped off, I have verified the brake is off, why would I only see the resistance to wind in the upright position but not be able to feel any at all as it is down?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    There are several possible reasons for the blades not turning.

    Failed bearings (spinning without electrical loads will still wear out the bearings) is a possibility. Failed mechanical parts internally (stator fail--magnets become detached/jammed/rub, field winding wires fail and fall jam into the rotating stator). Blades can fail too (high RPM from no-load--Alternator not connected to battery bank--Can let turbine over speed in high winds and shed blades and/or knock off tower). Usually all of these can be felt when spinning by hand.

    Another other reason for turbines not to spin... If the windings or rectifier or other wiring is shorted together. As the turbine begins spin, it moves current through the winding into the short--This current flow through the alternator causes reverse torque--And the turbine will very slowly turn, while the blades stall in the wind.

    Lastly, another issue could be the turbine is failing to turn into the wind--Possibly a failed yaw bearing?

    If a turbine is not being used, it should be "braked" or tied off so it does not spin. Or taken down and stored out of the weather. A free spinning turbine is just wearing out without any electrical benefits to you.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rodwood
    rodwood Registered Users Posts: 5
    Thank you Mike and Bill great advise,
    Because the blades spin freely by hand I am considering the main bearings OK, the short sounds reasonable but i remember before this started a higher wind barreled down on the gen  it it would not release back from the yaw position,shaking the pole from the bottom helped settle it back, so could may be the yaw bearing as Bill mentioned,  question on that ? Would a yaw bearing keep it from spinning in low winds that typically would not engage the yaw?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    In low winds, if the turbine is not facing dead into the winds (stuck or high friction yaw bearing), it will not spin much at all, even when free wheeling.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rodwood
    rodwood Registered Users Posts: 5
    Is there a function I can perform on the yaw bearing to verify prior to replacement?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Set up something near the turbine to show direction of wind? (ribbon on pole, etc.)

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rodwood
    rodwood Registered Users Posts: 5
    I'm still working this out, if by chance because I left it free spinning producing voltage with no place to go and it burnt or shorted would the blades by hand spin freely with the tower down?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Generally, no loading will just be more wear on the bearings.

    And in high wind conditions, the turbine can over speed and toss blades / toss magnets (from the rotor).

    No load over speed could cause over voltage and cause the rectifiers to fail open (no loading) or shorted (stall the blades).

    - Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset