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BrianG · 07.19.2006, 07:25 PM

Cool information jhautz!

That all makes sense when you think about it. Reducing the torque to a lower setting will gradually apply max power over a longer time reducing that huge spike of current at a standstill or heavy acceleration. Electric motors are known for a large inrush current when starting up which is why you see capacitors on a lot of AC motors. I wonder how far this torque delay setting would have to be increased to act like a Nitro? :005:

The battery high setting sounds like it just uncaps the current so the motor will draw as much as it wants, while the battery normal setting sounds like it acts like a sort of current limiter.

An ESC simply outputs a series of pulses whose duty cycle ("on" time to "off" time ratio) increases as the throttle is applied. The heat comes from the relatively tiny amount of time (probably measured in microseconds, if not nanoseconds) it takes for each of those pulses to go from their "on" state to their "off" state (called slew rate) since heat comes from voltage drop X current. Faster switching FETs (not to be confused with switching frequency) will switch faster and generate less heat. Anyway, adding a current cap with battery high/normal setting should really help reduce temps overall, while changing the throttle response will help curb heat somewhat if doing a lot of stops/starts and hard acceleration.

	(#15)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	07.19.2006, 07:25 PM Cool information jhautz! That all makes sense when you think about it. Reducing the torque to a lower setting will gradually apply max power over a longer time reducing that huge spike of current at a standstill or heavy acceleration. Electric motors are known for a large inrush current when starting up which is why you see capacitors on a lot of AC motors. I wonder how far this torque delay setting would have to be increased to act like a Nitro? :005: The battery high setting sounds like it just uncaps the current so the motor will draw as much as it wants, while the battery normal setting sounds like it acts like a sort of current limiter. An ESC simply outputs a series of pulses whose duty cycle ("on" time to "off" time ratio) increases as the throttle is applied. The heat comes from the relatively tiny amount of time (probably measured in microseconds, if not nanoseconds) it takes for each of those pulses to go from their "on" state to their "off" state (called slew rate) since heat comes from voltage drop X current. Faster switching FETs (not to be confused with switching frequency) will switch faster and generate less heat. Anyway, adding a current cap with battery high/normal setting should really help reduce temps overall, while changing the throttle response will help curb heat somewhat if doing a lot of stops/starts and hard acceleration.