Re: SRSG questions

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

Original poster: "Christoph Bohr by way of Terry Fritz <teslalist-at-qwest-dot-net>" <cb-at-luebke-lands.de>

This at least confirms what I have seen so far.
My motor is a 125Watt 2 Pole with a ca 5cm Rotor and I grinded 2 Flats
aproximately 2cm wide.
The MOT-fan motors attracted my interest too, but they are really unusable
for sync use....but now I finally know what the copper rings attached to the
stator are good for ;-)
Maybe I will look for a bigger Motor as I want to go for higher brakerates
by use of a bigger disk / more elektrodes to take advantage of my
4MOT-Supply on my relatively small 30nF tank cap.
When I have new results I'll post them on the list.

Christoph

---- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, April 23, 2003 1:52 AM
Subject: Re: SRSG questions


 > Original poster: "Stephen Conner by way of Terry Fritz
<teslalist-at-qwest-dot-net>" <steve-at-scopeboy-dot-com>
 >
 > At 16:10 22/04/03 -0600, you wrote:
 > >Original poster: "Christoph Bohr by way of Terry Fritz
 > ><teslalist-at-qwest-dot-net>" <cb-at-luebke-lands.de>
 > >
 > >Hi!
 > >
 > >I think we have a  similar problem....
 >
 > This is what I learned from the few university classes on electrical
 > machines that I managed to stay awake through.
 >
 > Some motors are more suited to sync conversion by grinding the rotor than
 > others. The best kind of motor is a 4-pole capacitor-run motor. You can
 > identify this kind because it has a motor run capacitor bolted to the
 > outside and it runs about 1450rpm (50Hz) or 1750rpm (60Hz) You grind 4
 > flats on the rotor and it should run synchronous at 1500/1800 rpm. My
cheap
 > $40 Chinese drill press has one of these, I would have converted it long
 > ago, but I find the drill press too useful to do without.
 >
 > Other kinds work less well. 2-pole types (rated around 2850/3450rpm) need
 > only 2 flats on the rotor and the flats have to be bigger with all the
 > torque problems that entails. Motors without a run capacitor don't do too
 > good either.
 >
 > The small shaded-pole motors you find in microwave oven fans etc don't
seem
 > to work at all. Some fairly large motors (100W) are actually shaded-pole,
 > they can be identified by the copper shading rings built into the stator.
 >
 > Steve C.
 >
 >
 >
 >
 >
 >