Re: 2 questions: SRSG & LTR Caps

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

Original poster: "Dave Leddon by way of Terry Fritz <twftesla-at-qwest-dot-net>" <leddon1-at-llnl.gov>

Matt,

I think you need a larger cap.  My SRSG is similar to yours:
>1.     Salient pole motor 1/5 HP 3600 RPM
>2.     7"  2-electrode disk
>3.     10A 120 V Variac
>4.     50uf -at-330V Cap
>5.     51K-ohm resister across cap
>6.     5A fuse
With this setup I get 85 degrees of phase shift using about 85% of the 
rotation of the
Variac control with a resonate voltage rise of 4 volts.

Dave

At 09:58 PM 3/18/02, you wrote:
>Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" 
><Mddeming-at-aol-dot-com>
>
>Tried firing up a SRSG with phase control tonight with dismal results. I
>suspect the components are of incompatible size. No significant change in
>phase(<5deg), even using modified strobe (per Terry) to check visually.
>
>1.     Salient pole motor 1/7 HP 3600 RPM
>2.     6"  2-electrode disk
>3.     3.5A 120 V Variac
>4.     15uf -at-660V Cap
>5.     47K-ohm resister across cap
>6.     5A fuse
>While I have lots of caps and resistors, but don't have a feel for 
>direction or
>order of magnitude of change needed. Anyone with experience please advise.
>
>For LTR Caps with 15 kV NSTs is the rule of thumb of 0.5nF per mA fairly 
>linear
>for 30-300 mA? i.e. 15nF -at-30 mA, 30 nF -at- 60 mA, etc.
>
>Thanks,
>Matt D.
>G3-1085