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Author Topic: speed related to torque  (Read 6459 times)

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ltmhall

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speed related to torque
« on: November 30, 2006, 09:03:28 PM »
How is speed of a dc motor related to torque.

Kohanbash

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Re: speed related to torque
« Reply #1 on: November 30, 2006, 09:22:48 PM »
torque is inversely proportional to the speed.
the motor's data sheet usually has a torque/speed graph.
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JesseWelling

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Re: speed related to torque
« Reply #2 on: November 30, 2006, 11:43:14 PM »
any body have any idea about voltage/amperage to speed/tourqe.
I know that a motor uses more amps to use more tourqe but... any thing else we should know?

Kohanbash

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Re: speed related to torque
« Reply #3 on: December 01, 2006, 07:08:07 AM »
just some useful stuff:

voltage is proportional to speed
torque is proportional to the armature current
torque is proportional to (output power/speed)
Horsepower=(torque * speed)/5252
also there are series, shunt, and compound DC motors. each have slightly different characteristics. for example: series motors have better start up torque and shunt has better torque vs speed characteristics.

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JesseWelling

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Re: speed related to torque
« Reply #4 on: December 01, 2006, 10:08:06 AM »
brushless?

Kohanbash

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Re: speed related to torque
« Reply #5 on: December 01, 2006, 01:40:49 PM »
Those are all for brushed motors.

Someone please correct me if I'm wrong but i think brushless motors behave similar to AC motors since a higher current= higher torque and more current modulated pulses = greater speed. They also have a better power efficiency than Brushed DC motors.
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Re: speed related to torque
« Reply #6 on: December 01, 2006, 01:42:19 PM »
brushless motors require a controller . . . probably closer to a stepper? havnt actually used one . . .

JesseWelling

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