The cut in speed will be determined by the diameter of the machine. You can find the rpm's that it will run using the following formula...
Windspeed x 88 / ( diameter x 3.14 ) x TSR = rpm
Windspeed in mph
diameter in feet
Tsr unloaded would be 1.6
Tsr loaded for peak performance would be 0.8
The "88" simply converts mph to feet per min.
On a 3ft diameter machine your looking at a cut in speed of 56 rpm in a 6 mph wind.
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