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sleebus.jones
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Join Date: Dec 2005
Location: Houston, TX
11.18.2006, 11:08 PM

Quote:
Originally Posted by glassdoctor
Actually this is not true at all... their numbers are correct.

Amp draw increases with voltage. Given the same motor, etc... more voltage always means more current.
Sorry, no it doesn't. As voltage goes up less amperage is needed to do the same amount of work. That is because of this relationship here:

Amps = Watts / Volts

Say for instance, we have a 1000w motor on a 6 cell pack:

139A = 1000w / 7.2v

Now, let's upgrade that to a 10 cell pack:

83A = 1000w / 12v

See? The amps went down, not up. If the amps stay the same when the voltage went up, that would mean the motor somehow make more power...which can't happen, because the motor is unchanged.

What this vendor is asserting with their numbers is that the same motor can do more work with more voltage. That makes no sense.

Sleebus
   
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