Re: tachogenerator

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "bondeoca" <rick@...> wrote:

>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@> wrote:
> >
> > bondeoca wrote:
> > > Hello All
> > > I have picked up a G E tachogenerator hoping to use it as a
> spindle
> > > drive motor for my mill.
> > > It is a pm rated at 100 volts per 1000 rpm.It is apprx . 7 inches
> in
> > > dia. and 10 inches long,has
> > > four brushes 180 degree spacing. When I apply 100 volts it
> > > rotates ,but with a 2 inch pulley
> > > on the shaft I can stop it by hand a turn it in the opposite
> direction.
> > > So my question is , is there something I can easily do to this
> motor
> > > to increase its torque?
> > > I also notice the magnets for being quite large , do not seem
> very
> > > strong.
> > >
> > It is NOT a motor! It is a measuring instrument, designed to
> accurately
> > measure the speed of some mechanism.
> > Since all electrical machines are reversible, it is similar to a
> motor,
> > but it is optimized all wrong for use AS a motor.
> > Other than replacing the magnets and windings, I think it will be
> > impossible to make it function well as a motor.
> >
> > Jon
> >
> Thanks Jon, I knew it wasn't a motor ,but a lot of sites say any
> dc motor can be run as a generator and visa versa. Do you know how
> the windings differ from a dc motor?
>
> Rick
>

For a start, bondeoca , as a generator the design would be less
worried about the heat produced by eddy current losses. Also, the
brushes and their wiring would be designed for longevity rather than
passing high current. It may work, but it will never work well as a
powerful motor.

Regards

David