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Old 06-27-2017, 05:46 PM
  #11  
Got RPM
 
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Join Date: Nov 2006
Location: AZ
Posts: 857
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Cool

End travel on transmitter throttle settings. On a good quality brushless esc with a high PWM rate running at partial throttle is no big deal, when using proper cooling. ....
This is not exactly true, especially in boats which draw far more current than any highly-geared 'crawler. Boats aren't trucks. Plenty of FE boaters think that part throttle is easier on their components than full throttle - not so at all. I have witnessed burn downs several times with new club members, and it is common to hear about on the high-traffic FE boat forum. But don't believe me, here is what one of the largest manufacturers of quality brushless ESCs has to say on the topic:

" A speed controller controls power to the motor by turning full throttle current on and off really fast, 11 to 13 thousand times per second (Pulse Width Modulation or PWM). The percentage of each on/off pulse that is off compared to the part that is on determines how much power the motor sees. I.E. With a pulse that is 50% off and 50% on the motor will see 50% power. Because each on pulse is 100% of full throttle current, a system set to pull 20 amps at full throttle through a Phoenix 10 will not last if you are throttled back to the point where you only see 10 amps on a wattmeter. The ESC in this case is still switching 20 amps, which it can’t do for long. Actually it is worse than the simple example above. Because an electric motor will always to try to pull as much power as is available to get to its rpm (volts times Kv), when you are running the motor below its Kv speed by switching power on an off, each on pulse will actually be way over the full throttle amp draw... Castle Creations"


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