Re: sync motor :-( update_1

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

Original poster: "Barton B. Anderson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <tesla123-at-pacbell-dot-net>

Hi Jonathon,

There were 4 flats cut, correct? I know this is probably a dumb question,
but I just
wanted to clarify here. I assume so since you stated flats cut at 90
degrees. Ok,
here's something else to help us out with your delema:

1) What is the size of the armature (diameter)?
2) What is width of flats AND the width of the non-cut areas between each flat?

Just curious on the mechanics of the work done. My flats were cut equal
(the spacing
between each flat measured the same as the flat width). Used a tach =
1800rpm and
solid. I have a centrifigal switch, but works like a champ. My sync motor
is rated
at 1/3HP, 1725rpm.

I like others really find it odd it isnt sync'd. When it comes up to speed,
is it
steady? If not, it may be trying to sync but losing sync (you can hear it
change
speeds near it's top end if this is happening). This is typically caused by
too much
resistance vs. HP. A 1/3HP motor shouldn't have this problem unless
something is
really thrown together wrong. Is there a load attached to the motor shaft?
If so,
what's the load?.

Regards,
Bart

Tesla list wrote:

> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Kidd6488-at-aol-dot-com>
>
> Hi again,
>       Ok, your replys on that cent. switch made a lot of sense to me. So I
> popped the motor apart again (after 6 times, one gets pretty good at it :-\)
> and looked at the contacts on the motor, and the centrifical switch on the
> rotor. Both looked good, but I still cleaned them up.
>       Also, when taking the motor apart the first time, I noticed a seal or
> something laying on my work area. I couldn't figure out where it went, so I
> put it in the housing end, in what looked like a seal area. I guess it didn't
> go there, because that was what was causing some of the heat, and -100 RPM. I
> know this because this last test, without the seal, didn't get hot, and was
> clocked at 1725 RPM.
>       I know the switch is good, because I saw it spark as it kicked off.
> For those of you not keeping up, this motor has flats, yet is running at 1725
> RPM (what it is rated at).
>       I also did the carboard circle thing with flourecent light, and it is
> noticeably out of sync. Do I really need a variac to fine tune the voltage?
> I'm not worried about phase shifting as of this point. I just want this dang
> motor to run sync....
>       Also, a couple questions:
>
>       1) would a 1/2" x 6" lexan rotor be ok?
>       2) what can I do about excessive endplay?
>       3) what kind of supports should I use to hold the stationary
> electrodes?
>
> I'm sure this thread will live for a while  :-D
>
> ---------------------------------------
> Jonathon Reinhart
> hot-streamer-dot-com/jonathon