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Re: Rotary Gap Question

Very interesting, it seems that lots of motors are syncronous, even
though it would not immediately seem so. I have a washing machine motor,
strangely enough it is an induction motor (no carbon brushes in sight)
and appears to have salient rotor (there are silver lines running down
it). It has wiring for 1400rpm and 2800rpm operation (there's also a
very sluggish speed of something like 150rpm for normal washing, the
1400 and 2800 being slow and fast spins), all of which are divisible by
50 (I have a 50hz mains supply). Can I assume it is a syncronous motor ?

My problem would then be fixing electrodes to the spindle, it has a
smooth aluminium flywheel, normally of course a belt would go round
this. I assume that using a belt drive would screw up all the
syncronicity.

Tesla List wrote:
> 
> Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
> 
> Hi Nathan,
> 
> At 05:16 PM 12/28/1999 -0800, you wrote:
> >Hello to all!
> >
> >Heres' ANOTHER message from me...
> >
> >I have a quick question about rotary gaps.  I understand with NSTs it would
> >be greatly to my advantage to have a sync motor running the gap.
> 
> A sync motor will fire at exactly the same point on the AC sine wave that
> is charging the primary cap.  Thus, your system will fire just when the cap
> is fully charged.  A non sync gap will fire randomly during the charging of
> the cap and about 1/2 the power will be lost.  Worse yet the neon will see
> all kinds of over and under voltages that may kill it (probably not).  The
> real danger is if the gap does not fire and the voltage skyrockets past
> were the neon or cap will blow up (there was just a song written about this
> here on the list ;-))  One thing to always have is a second set of fixed
> gaps just across the neon that will fire in case the main gap does not.
> These are what we all refer to as safety gaps.  When all else fails, these
> simple gaps will fire and protect the neon and caps form over voltage.
> Normally they will not do anything.
> 
> >
> >The motor I have obtained is a turtlish 1000 RPM induction motor.  Is the
> >only difference between sync and induction motors that they have different
> >RPMs? (The sync's RPMs being a muliple of 60)
> 
> Assuming you have 60Hz AC where you live.  You will want a 1725 RPM motor
> of about 1/4 horsepower.  These can be converted to 1800.00 RPM with some
> work.  I don't think your 1000 RPM motor can be converted.  See the follow
> pages for motor conversion info and a bunch of pictures of my sync gap.
> 
> http://www.peakpeak-dot-com/~terryf/tesla/misc/syncmot.zip
> 
> http://www.peakpeak-dot-com/~terryf/tesla/misc/RGAP.ZIP
> 
> http://www.peakpeak-dot-com/~terryf/tesla/experiments/modact/modact.html
> 
> >
> >If that were true, then couldn't I put a high quality speed control on the
> >motor, run it at 900 RPM with 8 gaps, 120 breaks per second, and ride the
> >sin waves like a surfer?
> 
> Trust me, you won't be able to do it well enough.  You will also have other
> things on your mind and messing with the gap trying to chase the AC wave
> will not be worth it.  There really are motor controllers that would do it
> (exact RPM plus phase control) but they far are too elaborate for our use.
> They are also highly electronic and may just get fried if (when) something
> arcs.  Getting a regular motor and modifying it is the best way to go.
> Many people have thought of all kinds of other wonderful ways but about
> 100% of the sync gaps use modified motors.  Hint, hint ;-)
> 
> >
> >Or has my train of thought wandered too far, and assumed too much?
> 
> Nope!  your right on track asking all the right questions.
> 
> Cheers,
> 
>         Terry
> 
> >
> >Thanks,
> >Nathan
> >______________________________________________________
> >Get Your Private, Free Email at http://www.hotmail-dot-com
> >