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KV rating on same size motors?

Whats the difference?

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4 replies to this topic

#1 Buddy Benedict

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Posted 24 December 2017 - 11:37 AM

The two motors listed below are the same size but have different KV ratings. Besides the voltage and amperage difference, what is the reason for having the different KV.   Is it for more RPM's or more torque or what?

 

https://hobbyking.co...less-motor.html

 

https://hobbyking.co...less-motor.html





#2 Steven Bryant

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Posted 24 December 2017 - 11:47 AM

Different KV allows the motors to be used at different voltages, I.e 8s, 10s etc


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#3 BrianTooms

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Posted 24 December 2017 - 03:43 PM

KV x Volts = RPM :)



#4 LohringMiller

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Posted 25 December 2017 - 08:44 AM

KV has NO influence on power.  It's a measure of the ratio of rpm to voltage as posted above.  Power is volts times amps.

 

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#5 HTV Boats

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Posted 26 December 2017 - 09:34 AM

On the same size motors different windings produce a range of KV ratings. As stated for different voltages. If you had a 4400kv on 2S it would produce the same rpm as a 2200kv on 4S and 1100kv on 8S. Amp draw on same boat and prop approximately would be X on 2S, 1/2 X on 4S and 1/4 X on 8S. if the 2S was 200 amps the 4S would draw 100a and on 8S down to 50a. Work done with volts over amps.
Or consider KV like gears. With the same voltage and prop going from 1800kv to 2030kv speed would increase if you weren't over propped. Or same kv's and a prop that was on the edge heat wise going down on kv should run cooler for the same laps.
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