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BrianG · 05.28.2006, 03:11 PM

I imagine most people with limited battery space are stuck using low voltages (unless they go Lithium), so they almost have to choose a low kV/high amp motor to compensate. It seems that trucks where space is not as much an issue should use a high wind, higher voltage, and then gear up.

I look at it this way; if I want 2 HP (which is around 730 watts), do I want high voltage and low current, or low voltage and high current? High current requires heavier wires, more heavy duty ESC, require beefier batteries, and more losses due to voltage drop and heat. Of course, your gearing options limit you somewhat as well; if you can't go above or below a certain gear ratio, then you are limited in choices for whatever top speed you are aiming for.

I'll tell you, there isn't much difference in real world speed between my 8XL and 10XL on 14 cells, but the truck using the 10xl is a bit lighter.

On a related note, does anyone know what the voltage limit is for these motors? I mean the voltage that it would take to arc through the thin varnish (insulation) on the winding. This is sometimes called a hi-pot test (high-potential). Not that we would run anywhere near that voltage, since it's probably ~200v+ but it would be nice to know how high we are able to go provided we stay at a safe kv rating.

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BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	05.28.2006, 03:11 PM I imagine most people with limited battery space are stuck using low voltages (unless they go Lithium), so they almost have to choose a low kV/high amp motor to compensate. It seems that trucks where space is not as much an issue should use a high wind, higher voltage, and then gear up. I look at it this way; if I want 2 HP (which is around 730 watts), do I want high voltage and low current, or low voltage and high current? High current requires heavier wires, more heavy duty ESC, require beefier batteries, and more losses due to voltage drop and heat. Of course, your gearing options limit you somewhat as well; if you can't go above or below a certain gear ratio, then you are limited in choices for whatever top speed you are aiming for. I'll tell you, there isn't much difference in real world speed between my 8XL and 10XL on 14 cells, but the truck using the 10xl is a bit lighter. On a related note, does anyone know what the voltage limit is for these motors? I mean the voltage that it would take to arc through the thin varnish (insulation) on the winding. This is sometimes called a hi-pot test (high-potential). Not that we would run anywhere near that voltage, since it's probably ~200v+ but it would be nice to know how high we are able to go provided we stay at a safe kv rating.