Re: Stepper motor as an encoder

Mariss,
I posted the links to show some people are using steppers
as encoders and that they do work in some applications!

Bob

--- In CAD_CAM_EDM_DRO@y..., "mariss92705" <mariss92705@y...> wrote:
> Bob,
>
> Nice circuit but it still doesn't get around the problem. The
circuit
> has a miniscule amount of hysterisis to latch the output to the
last
> signal peak, + or - . It would work down to 1/3 RPM as stated as
long
> as the detent torque is unloaded. The detent torque causes
momentary
> velocity to generate a voltage on the coils. A real world load
would
> swamp out this effect, rendering it useless at speeds below 1/2
RPS.
> It also cannot address sensitivity to vibration (microphonics) at
> these very low speeds.
>
> To qoute from the listed page, note the honest caveat:
>
> "The problem with a stepper (or any other motor) used as a
generator
> is that at very slow speeds it gives virtually no output - so there
> is a problem with slow speeds. You have to make some sort of trade
> off between high speed and low speed performance. Proper encoders
use
> optical switches which work at any speed."
>
>
>
> Mariss
>
> --- In CAD_CAM_EDM_DRO@y..., "cncdxf" <cncdxf@a...> wrote:
> > Hi,
> > The link below sums it up.
> >
> >
> > http://www.4qdtec.com/stpen.html
> >
> >
> > Bob