Re: An intersting idea for ballast.

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Steve White by way of Terry Fritz <twftesla-at-qwest-dot-net>" <slwhite-at-zeus.ia-dot-net>

Any idea of using a brake to apply  a load to this motor may not be any more
efficient than pure resistive ballast. When you use a brake to apply a load
to the motor you are dissipating the excess power as heat. This is precisely
what a resistive ballast does.

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, August 31, 2001 9:36 AM
Subject: Re: An intersting idea for ballast.


> Original poster: "Metlicka Marc by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <mystuffs-at-orwell-dot-net>
>
>
>
> Tesla list wrote:
> >
> > Original poster: "D.Wightman by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <dwightman-at-mmcable-dot-com>
> >
> > Some of you may think that I am totaly crazy, But just possibly some of
> you may
> > think that this is a brilliant idea!
> > I am a heat and air technician by trade. And just today this dawned on
> me. You
> > will find that all A/C motors have something called "LRA". That is
locked
> rotor
> > amps.
> > Ok here is the idea, Let's say that you get a 3hp 208-230 vac single
phase
> > electric motor.The LRA is 75 amps.
> > Now you hook up your pig in series with the input wiring to the electric
> motor.
> > Next you attach a second electric motor to the first motor . This will
allow
> > you to vary the speed of the rotor in the first motor that is
> > wired in series with your piggie, or nst. Ahaa!!!! you now have a
variable
> > ballast! If you look at the data tag on the electric motor that is being
used
> > as your variable ballast you will also notice that there is another term
> called
> > "RLA" that is running load amps. On a 3 h/p motor at 230 vac it will be
> around
> > 17 to 20 amps.
> > But the RLA is around 75 amps. Let's say that the motor is a 1075 rpm.
That
> > means that if you can turn the rotor at 1075 rpm you will allow only 17
to 20
> > amps to your tranny. If you can slow down the rotor the amperage will
get
> > higher, the slower the rotor turns the higher the amperage flow will be.

> If you
> > do not allow the rotor to turn at all the amperage through the motor to
your
> > tranny will be the RLA of the motor. This is just Brilliant!!! Who needs
a
> > welder? These electric motors are everywhere for real cheap.
> > Well what is everyone's thoughts?
>
> If this works in practice, I think it's great!
> Maybe a disk brake for locking the rotor and a hefty motor with tach
> feedback?
> Or better yet a motor WITH electric brake and tach feedback, Adjustable
> on the fly just with a turn of a knob, WOOHOOO!
> Great thinking, I Might have to start looking for a good motor?
> Marc M.
>
>
> >
> >
> >
> >
> >
> > "Nature has stored up in the universe infinite energy.
> > The eternal recipient and transmitter of this infinite energy is the
ether".
> >                                        Nikola Tesla. May 20, 1891.
>
>
>