A friend has a 70vdc ,3450 rpm,12 amp servo motor.After doing your calculations my rpm ratio is 0.020 x 700=14 x85% =11.9.Obviously this is just under 12 volts but is it close enough to charge a 12 volt battery pack.Just curious where the 700 rpm figure came from.Thanks in advance
It is right on the cusp of being able to create the required rpm. Since it is free, it is probably worth a try but you might want to consider gearing it at a ratio of 3 to 1.
