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Old 10-29-2014, 10:20 PM   #11 (permalink)
Grant-53
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Join Date: Feb 2010
Location: Elmira, NY
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I don't want sound like a know-it all but I used to build slot car motors. The only thing that normally ruins permanent magnets is heat. The motor does not turn DC into AC but sets up and collapses the armature field rapidly. Good bearings and dynamically balancing the armature allow the maximum rpm. We would coat the armature windings with epoxy to keep the wire from flying off at 100,000 rpm. Ampere/turns produce the torque. Heat melts wire insulation, usually a lacquer coating on the wire, and the plastic parts holding the brushes if there are any. Keeping the air gap between fields to a minimum is key. Air flow axially is helpful. Temperature raises resistance in wire and this reduces the amperes in the windings. Increasing the voltage does push more current for a given resistance. To make a scooter go faster there must be sufficient torque at the desired rpm and air drag increases exponentially with speed. So to get more total output amperes and voltage are needed. The controller may be the limiting factor.


Last edited by Grant-53; 10-29-2014 at 10:26 PM..
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