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A BLDC I have is rated at [itex]\begin{equation}285W\end{equation}[/itex] and [itex]4700Kv (rpm/V)[/itex].

So I was wondering if my calculations are correct.

Using the relationship between Torque and Power and angular speed

[itex]

\begin{equation}

\begin{split}

\omega &\approx 700rads^{-1} \approx 6700rpm\\

T &= 0.412Nm \\

P &= 285W

\end{split}

\end{equation}

[/itex]

From this get the voltage from the motor specs

[itex]

\begin{equation}

\begin{split}

V &= \frac{6700}{4700}\\

&= 1.42V

\end{split}

\end{equation}

[/itex]

So now using the fact that

[itex]

\begin{equation}

\begin{split}

K_t &= \frac{1}{K_v}\\

T &= K_t i

\end{split}

\end{equation}

[/itex]

Therefore

[itex]

\begin{equation}

\begin{split}

i &= K_v \times T\\

&= 4700 \times 0.412\\

&= 1936A

\end{split}

\end{equation}

[/itex]

This result makes no sense because that is a tonne of current.

Assuming 100% efficiency (P = IV)

[itex]

\begin{equation}

\begin{split}

285 &= i \times V\\

i &= 196A

\end{split}

\end{equation}

[/itex]

Which again seems really really high.

Am I missing something somewhere? Will the motor not draw that amount of current at the given loads/speed? I am confused as I think the equations are correct....?