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Unread 22-11-2014, 10:12
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Re: Motors: Past and Future

Quote:
Originally Posted by BBray_T1296 View Post
I don't know why this would even matter.
It matters a lot. See below.

Quote:
The PDB will only supply 40A (at 12 volts) to a motor, or the individual breaker will reset.
The breaker doesn't reset instantaneously.


Quote:
Stepping up the voltage to 18V drops your maximum amperage to just 26.6 amps.

I haven't looked at the specific motor torque/rpm/current curves, but barring inefficiency, they can only operate at the same maximum power
The power you are referring to above is the input electrical power.

Operating at higher voltage makes the motor much more efficient. The output shaft mechanical power at 18 volts and 26.6 amps is much greater than the power at 12 volts and 40 amps.