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    Throttle sensitivity

    For some reason the graph pic is not downloading correctly, but I understand the response is non-linear. To me, a throttle should be slightly non-linear, but least sensitive to movement at the low end and increasingly sensitive toward the high end. This gives you more control when driving...
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    Fechter's current based throttle

    At a given setting, the current mode throttle will maintain a constant input power to the motor until the load drops off. If I give it 1/4 throttle for example, it would accelerate to full speed (and full motor voltage) if the full speed load is under that current limit. Like going downhill...
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    Bigger Motors are Better

    One thing to keep in mind is a bigger motor generally has a higher no-load current. This means at low power levels (riding slow) a bigger motor will have higher losses. An Etek motor takes about 6 amps just to turn over. My MAC BMC motor takes about 2 amps. For a given maximum power level...
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    How to test MOSFET's

    I agree with the part about the gate drivers blowing. I've seen that happen repeatedly. Using tiny gate resistors works like a charm. I usually get the FETs to blow up real good so they're easy to spot. No question about this one:
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    Electricly insulating heat transfer material

    Another approach is to bolt the FETs directly to a hefty bar of aluminum, then use the rubber stuff to insulate the bar from the case. This allows heat transfer over a much larger surface area and doesn't allow the FETs to heat too rapidly. In your controller, this looks like it would be hard...
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    Fechter's current based throttle

    Using a hall current sensor would eliminate some of the guesswork for the resistor values. For my setup, I would need a 100 amp one. The hall sensor has several other advantages, like temperature stability and high sensitivity. The "existing wire" shunt setup was used mainly because I'm cheap...
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    Electricly insulating heat transfer material

    The original rubber stuff is silicone. It actually does a really good job of tranferring the heat and not melting despite it's thickness. I usually put some heasink compound (grease) on them as well. Mica is also good, but is brittle and must be handled carefully. Grease that stuff too...
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    Fechter's current based throttle

    Gee, I guess they'll let anybody join this board. Sorry I didn't get over here earlier. It sounds like Mathurin has a good understanding of how it's supposed to work. Throttle position controls the current limit from zero to whatever max you want. This should work wonders for increasing...
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