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Well, according to my EXTREMELY SUSPECT calculations, your motor is best
run at around 12,000 rpm, where it should draw around 13 amps. Assuming
that the motor is 50% efficient, it should be generating around 0.05 ft-lbs
of torque and 0.10 horsepower. If the motor is 75% efficient, it should be
generating 0.07 ft-lbs of torque and 0.15 horsepower.
You can tell how efficient a motor is by measuring the stall torque - the
higher the torque, the more efficient. In your case, 0.23 ft-lbs works out
to about 50% efficient, and 0.35 to 75%. (Efficiency is good not just for
battery life, but also HEAT - potentially enough to let the smoke out.)
I hope this helps. (I also hope it's right!)
Bill
At 05:08 PM 9/5/2003 -0500, you wrote:
>I would like to see if any of you could help me with some electric motors
>I bought at a local surplus store. They are 12 volt , 4.100" overall
>length , 2.030" Dia. , 5MM (.1969) Dia. shaft., Internal fan
>cooling , 14,500 RPM free speed. It pulls 3.4 Amps at no load. Pulls 50
>Amps at stall. Any idea what an average load RPM and AMP draw might be?
>Given a gear reduction of 25 to 30 to
>one. Thanks Randy
--
"Forgive your enemies, but never forget their names" -- John F. Kennedy