10S or 12S I'm so indecisive!

Hell probably back off with the current if he goes 12s

you’re drawing the same amount of watts, but isn’t Amps the one creating heat? i believe this is the reason powerlines have insane voltage and low wattage

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  • 2000W / 37.0V = 54A @10s
  • 2000W / 44.4V = 45A @12s

This is A good example in thoery both setups should produce similar heat output although not porportional

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You guys do realize that in order to take advantage of the reduced current of the higher voltage battery for the same power, you would have to reduce the gearing?

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No, because the ESC changes output voltage going to the motors for you. :slight_smile:

Edit: But IIRC, it is more efficient if the voltage conversion is close to 1:1 / if you go at max speed. Going at max speed will increase your range, or at least I think I’ve heard that somewhere.

This shall do

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yes, i did this on my own board :slight_smile:

i’ve got 12S on 190KV motors, reduced the gearing to 1:3 which gets me a topspeed of 25Mph which is the max speed i’d like to go right now. the torque benefits of this as well!

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You mean amps?

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I’m not certain if the ESC acts like a current source or voltage source, but the ESC changes the speed for you, so all the battery does is change the max speed you could reach.

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Yeah my electrical theory is weak at best. I get how all the pieces relate in Ohms Law . I just always go back to not needing as beafy of cables to achieve the same wattage when using higher voltage versus higher amperage. Once all of that hits the ESC and flows to the motors it gets murky for me.

Not true. your still passing the same amount of energy through the cable…

In the battery wires you’ll have to run more amps if running a lower voltage and want the same wattage. In the motor it’s all the same and just as hot and same amps needed. In the esc lower voltage is more eff but at full speed u have no switching losses so more efficient. So u could run more voltage n be less efficient when at reduced throttle vs lower voltage and full throttle. But that’s a real exception

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not needing as beafy of cables to achieve the same wattage when using higher voltage versus higher amperage…

Ok that came out wrong, what I meant to say was not that you won’t achieve the same wattage, but in order to be able to achieve the required wattage without significant voltage drop or creating too much heat and melting you insulation off of your cable you will need a beefier cable if you have high amps and low voltage versus high voltage and low amperage.

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Yes true, higher volts, less amps for the same power. So for the same power you don’t need as thick cables. Cable thickness is only related to amps, not power.

Think about it, 100V @ 1A = 100W, only need a thin cable. 1V @ 100A = 100W, but you need a very thick cable. In fact the cable needs to be 100^2/1 = 10000 times the area or more because of the lower surface area vs cross section.

so your telling me i can run 400v through a cable and i dont need thick cables?

Yes. Look at how thin the cables are for high voltage backlights in the back of TVs etc. Of course you need to have decent insulation at 400V but for 10s vs 12s the insulation requirements are not relevant.

haha was meant to be a joke but my apartment uses 8 guage copper wire, and all silicon wire is rated for 400v :joy:

If you have heavy gauge wiring in your apartment, it is to handle CURRENT not voltage. Wire is not made from silicon. Not all SILICONE insulated cable is rated for 400V.

Sorry misworded that i was thinking of turnigy wire, but my apartments wires only claim to be up to 20a

Current rating for household wiring is completely different for ratings for skateboards and other hobby devices. Standards for household wiring are to prevent fires in walls and that kind of thing and so are extremely conservative.