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Voltage limits on brushless motors.

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Old 06-16-2014, 05:29 PM
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1fasthitman
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Default Voltage limits on brushless motors.

If I use a 10 cell lipo on a brushless motor rated for up to 8 cells,
is the problem with doing that, the extra power or is there circuitry
in the motor that won't operate properly? I thought about doing it while
using a smaller prop to keep current draw down to stay within max watts.
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Old 06-16-2014, 07:37 PM
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jetmech05
 
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Your confusing voltage with amps. Volts push amps through resistance. Too much voltage and you'll see the magic smoke. Once you see the magic smoke it won't work any more. The more cells on a battery the more voltage
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Old 06-17-2014, 05:26 AM
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jester_s1
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There is no circuitry in a brushless motor. There is, however, a limit to how many amps the windings in the motor can handle. If the manufacturer gives you a range of operation, you'd do well to stick with it.
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Old 06-17-2014, 06:32 AM
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chuckk2
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The motor insulation is one of the factors that determine maximum applied voltage.
Next, the maximum current is a factor.
Assuming a brushless motor, and an ESC that applies full voltage pulses to the motor,
It's possible to have peak currents that are higher than the motor is designed for if the applied voltage is too high.
An 8S lipo is about 32v. add 8 more volts for the additional two cells you mention.
One of the complications is that the HV ESCs can get a bit pricey when you go above 6S.
Props also have an RPM limit that depends on the length and type of the prop.
Finally, an ESC provides pulses at a rate. It can be that the motor RPM has a limit determined by the ESC.
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