Motor Theory Head Check Needed

[mclovin]

Yo,
I tested a Chinese BLDC and am starting to "run" the numbers.

I measured:

Kv=27.97 rpm/V
Kt=.252 lb-ft/A
Rmotor=.043ohms
Noload: Io=1A, speed=1324rpm @ 48.6V (batt)

So, here's where I need my head checked - if tis motor is stalled then the current at 48V through the .043ohm motor will be 1116A. I base this on the equation V=E+IR (applied voltage=backemf+IR). Since at stall there is no backemf then V=IR.

I'm a bit stymied as the motor current at stall seems extremely high.

Also, maximun theoretical mechanical output is equal to V^2/(4R). In this case that equals 13395W. Again, this seems extremely high especially since the motor is rated for 500W at 48V.

Maybe I have this correct but need not be concerned since the current limit in my controller is what really governs the current and power of the motor.

Any thought are appreciated.

Cheers.

[Arlo1]

Yo,
Maybe I have this correct but need not be concerned since the current limit in my controller is what really governs the current and power of the motor.

Any thought are appreciated.

Cheers.

yup

[John in CR]

Yo,
Maybe I have this correct but need not be concerned since the current limit in my controller is what really governs the current and power of the motor.

Any thought are appreciated.

Cheers.

yup

and thank goodness it does too. I wouldn't even be able to ride my SuperV if the controller didn't tightly control the current.