Sensorless question

[barry]

Out of interest, why aren't sensorless brushless motors specified in turns, but kv instead?

Cheers,
Barry

[Col]

Barry, the correct question is this: why are only us RC cars users the ones who use "turns" when the rest of the industry use kv...?

[barry]

Originally Posted by Col

Barry, the correct question is this: why are only us RC cars users the ones who use "turns" when the rest of the industry use kv...?

Thanks Col. Is there a direct relationship between turns and kv? I mean, do all 10.5t motors have the same kv value?

Ta,
Barry

[Col]

you would have thought so, but aparently some 10.5's are more equal than others...

From what little I know, a cheap 10.5 is more likely to have a lower kv rating than an expensive one.

[Ferret]

Sensored motors usually have a similar construction (I think it is to comply with governing bodies rules) so 2 motors with the same number of turns will give similar performance. I also think that rating in turns was first started to make things easier for people who "grew up" on brushed motors.

Sensorless motor, however, are usually built with differenet construction techniques such as slotted/slotless, delta wind and wye wind and different rotor diameters. That means that motors with same number of turns can have very different performance, make rating by turns pretty useless.

Avner.