Re: motor start/run windings??

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

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

Hi David,

I doubt it's synchronous. Probably AC 1750 or 1725 rpm (hot, neutral, earth
ground). Do some tests
on it. Check the housing agains each of the wires. You'll probably find
one. That should be earth
ground. The other two will be AC lines. Probably wired for 240VAC. I use
one of these for my spark
gap motor, however, it's wired up for 120VAC and I modified (via 4 flats
cut into the rotor) for
1800 rpm sync.

Bart A.

Tesla list wrote:

> Original poster: "David Knaack by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <dknaack-at-rdtech-dot-com>
>
> I have salvaged the 1/4hp motor out of a clothing
> drier, hopefully for use in rotary spark gap.  It
> appears to be a synchronous motor.
>
> It has three input wires, black, yellow and red.
> I assumed that black was ground, and attached it
> to my variac.  I then flipped a coin and attached
> a lead to one of the other leads.  Flip the power
> switch and FFFFTTT, the magic smoke all squirted
> out of the small-gauge lead.  So I put a new lead
> on the other input, and the motor spins up, and
> a centripetal switch of some sort on the shaft
> clicks.  The motor then seems to run at a constant
> speed.
>
> The problem is that the motor windings get warm
> to the touch in less than 30 seconds.  I don't
> know if I've got things connected correctly or
> not.  I was thinking maybe I'm powering the start
> winding or something, but the diagram on the
> schematic shows the start and run windings connected
> to an internal switch, which I think is the one I
> see change positions when it gets up to speed, so
> I kind of thought it would handle switching start
> and run windings itself.
>
> Anyway, any suggestions would be appreciated, I can
> provide pictures of the motor and the schematic that
> came out of the dryer if it would help.
>
> Thanks
> DK
> --
> 99 little bugs in the code, 99 bugs in the code,
> fix one bug, compile it again, 101 little bugs in the code.