Re: rotary gaps+- problems

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

Original poster: "bob golding by way of Terry Fritz <twftesla-at-uswest-dot-net>" <yubba-at-clara-dot-net>

HI all,
    Been having some problems with the motor for my rotary. After designing
the whole thing around a
centrifuge brush motor  when I went to fire it up I discovered that the
electronic controller has died :-(
after trying to fix it I decided it would properly die as soon as I put the
coil on anyway. It is a series
wound brush motor with a start winding on one of the field coils as far as
I can tell. it has three wires
coming off it so I assumed that if I put a cap between the two wires coming
off the field coils it should
work. It does but doesn't seem to to have much torque. It is rated at 300
watts and draws around 2 amps at 180
volts. The cap I am using is 16 uF at 250 volts. It should turn my `12" x
1/2" rotor as the centrifuge hub
that was on it is heavier than my rotor. Should the size of the cap affect
the torque? I am leaving the cap in
circuit when the motor is running. Will this make any difference. The motor
spins up to 5500 RPM with no
trouble without the rotor on. Help! I don't want to change the motor if I
can help it as this will mean a
major redesign.

cheers
bob golding