Peter L. Peres wrote:
>
> >Second, brushless motors are current operated devices
> >(obviously) and you should operate them at the correct
> >spec current. Like steppers they usually have low-turns
> >(low ohms) coils, and are meant to be driven with some type
> >of constant current supply, like a chopper etc. In short,
> >you need some type of pwm etc on the motor coils to establish
> >correct running current.
>
> This is new to me. Could you indicate a reference for brushless motors
> being made for use with constant current supplies ?


Hi Peter, maybe "constant current supply" is a little
too literal, I meant that the motors are very low turns
and attention to CORRECT current needs to be a function
of PWM current limiting etc, ie deliberate, rather than
just connecting a power supply which will cause the
symptoms he saw, of 40x the specified current.

Most of the VCR 3-coil flatmotors I have here have
only a handful of turns on each of the 3 coils, they
are almost short circuit to measure.

So by "constant current supply" I meant a "current-controlled
supply that only allows a fraction of the current that
would flow it it was turned on constantly". ;o)
-Roman

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