Re: Type of variacs for SRSG Phase Controller

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Esondrmn-at-aol-dot-com>

In a message dated 12/16/02 4:22:38 PM Pacific Standard Time, 
tesla-at-pupman-dot-com writes:


>My current SRSG is run via a 1/25HP Synchronous Motor (hysteresis type -
>hence the need for phase control).
>
>Is there any reason I wouldn't be able to use a mini 3.5A, 120VAC variac for
>a phase controller????
>My initial tests worked a bit, but the motor would shutdown after about 50%
>adjustment.  I guess I need
>to fine tune my capacitance a bit.
>
>This would even further increase my available control panel space for
>additional meters, switches, etc...
>
>Thanks
>
>Dan


Dan,

I believe we have the same C and H Sales motor.  The smaller variac should 
work if you can find the right capacitor combination.  That said - I am 
currently using a 10 amp 120 volt Powerstat variac with an 18 ufd cap and 
get about 90 degrees of phase control and can use almost the whole range of 
the variac.  I have another 9 amp Powerstat 240 volt variac that I could 
find no capacitor value that would allow the motor to run when the variac 
is set above 50 % of full value.  The inductance measurements of both 
variacs are not that far apart.  The motor locks into sync at about 72 volts.

Ed Sonderman