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Old 10-31-2010, 03:44 AM   #1
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Default Is it possible to under gear and thermal??????

As the title suggests, it is possible to under gear a motor and thermal the ESC?????
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Old 10-31-2010, 04:16 AM   #2
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As the title suggests, it is possible to under gear a motor and thermal the ESC?????
Yes... Because the fets have to switch faster due to the constant higher rpm under load.
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Old 10-31-2010, 04:26 AM   #3
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Electric motors have a sweet spot that they like to run in. So temp can come from being under and over geared.
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Old 11-01-2010, 09:52 AM   #4
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As the title suggests, it is possible to under gear a motor and thermal the ESC?????
People say this is possible but I have never actually experienced or witnessed it. I have done a lot of RTR ESC testing and under gearing always producers lower motor and ESC temps.
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Old 11-01-2010, 10:05 AM   #5
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Under gearing will cause the motor to thermal especially on a large track when the timing kicks in it forces the motor to rev higher to produce more RPM and this will cause heat.
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Old 11-01-2010, 10:14 AM   #6
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Under gearing will cause the motor to thermal especially on a large track when the timing kicks in it forces the motor to rev higher to produce more RPM and this will cause heat.
you may also beable to retard the timing to reduce this.
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Old 11-01-2010, 02:41 PM   #7
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People say this is possible but I have never actually experienced or witnessed it. I have done a lot of RTR ESC testing and under gearing always producers lower motor and ESC temps.
I agree, I have been told on many occasions that it is possible, but never personally witnessed it. Furthermore, if we limit the discussion to thermalling the ESC (as per the original question) I don't really see how it could be possible. Increased switching frequency was mentioned above, but the same amount of power is being dissipated in the ESC no mater how fast it is switching (excluding what should be negligible switching ineffeciencies). I simply don't think is is possible to make the system ineffecient enough by undergearing to cause a problem.
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Old 11-02-2010, 02:43 AM   #8
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The extreme case of under gearing would be running the motor without a pinion. No load, high revs. So should be easy to test.
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