Higher ESC amp with higher kv motor?

[Koiartimus]

Maybe a dumb question, is it ok to run, let's say, a 150amp with a higher kv motor, like a 3200. My thinking is that having a higher amp ESC gives more room for motor choice, which allows for more choices in battery used, 3s to 6s, depending on motor kv. Or is it bad to run that way? Hope that makes sense.

 

[jondilly1974]

Maybe a dumb question, is it ok to run, let's say, a 150amp with a higher kv motor, like a 3200. My thinking is that having a higher amp ESC gives more room for motor choice, which allows for more choices in battery used, 3s to 6s, depending on motor kv. Or is it bad to run that way? Hope that makes sense.

Yep it’s voltage that could be an issue. Don’t over volt a motor. They will pull as many amps as they need. Amps aren’t pushed like volts.

 

[Koiartimus]

Yep it’s voltage that could be an issue. Don’t over volt a motor. They will pull as many amps as they need. Amps aren’t pushed like volts.

Thank you, That's kind of what I thought, but wasn't really sure, I just like to have options.

 

[slick2500]

General rule of thumb is to try to stay below 50k Rpms as well.

 

[Lawzy]

Yep it’s voltage that could be an issue. Don’t over volt a motor. They will pull as many amps as they need. Amps aren’t pushed like volts.

Is it possible to calculate the theoretical amp draw of a motor at maximum rpm?

 

[jondilly1974]

Is it possible to calculate the theoretical amp draw of a motor at maximum rpm?

Yes. You can take the motors max wattage and divide it by your theoretical voltage under load. That should give you an appropriate max amperage. If running 6S, a good theoretical voltage would be about 22v under load. This voltage depends on so many factors that it’s hard to be accurate without testing. No two setups will ever be the same.

 

[Lawzy]

Yes. You can take the motors max wattage and divide it by your theoretical voltage under load. That should give you an appropriate max amperage. If running 6S, a good theoretical voltage would be about 22v under load. This voltage depends on so many factors that it’s hard to be accurate without testing. No two setups will ever be the same.

Thanks, that is a useful guide.