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Old 07-31-2010, 12:02 PM   #3617 (permalink)
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Originally Posted by MPaulHolmes View Post
So, you would want to start in series mode, which has greater torque, and then switch to parallel mode for higher top speed. The goal is to maximize torque I guess, which is to say, maximize current. How could you do that automatically without a speed sensor? That would be nice!
Yeh thats its exactly. Say the controller pushes 200amps through the motors in series mode. Then each motor gets 200amps at half the voltage to maximise starting torque. Then when sufficient speed is obtained , switch to parallel. Now each motor would see 100amps but full pack voltage for max speed. Sort of like a 2 speed gearbox. My plan is to have a thumb switch for the driver (rider?) to change up or down. This is a drawing done by Tesseract over on diy.
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Now, Cole, when you shift the gear and that little needle on the ammeter goes into the red and reads 2000 Amps, that's bad.
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