Re: Another 942 run

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

Original poster: "John Richardson" <jprich-at-up-dot-net> 

Hi Dave,

It will only do this when I am turning the phase controller beyond it's 25%
from minimum point.  This leads me to believe that I'm throwing the SRG
phase off enough to force the safety to fire.  When I adjust the phase in
it's sweet spot, however, she doesn't fire safety gaps or pop breakers.  I'm
hoping to get time to go to our tool van and retrieve my digital multimeter
and recheck that I have the proper capacitance for this motor, variac, and
total phase shifter.  The analog Triplett meter is difficult to read when
looking for small voltage differences.  The two safety gaps need a little
fine tuning, and I think they will be fine.  I'll try to get my clamp on
adapter for the Triplett up and working, and get backwith some actual amp
draw ratings.

Thanks,
John
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, March 09, 2004 1:00 AM
Subject: RE: Another 942 run


 > Original poster: "Dave Kyle" <dave-at-kyleusa-dot-com>
 >
 > John,
 >
 > I am not the expert as others on this list are but your popping a 20 amp
 > breaker with a 12KV -at- 120 with PFC caps is suspicious to me. I had a
similar
 > experience with 15KV -at- 90 running a SRSG. My gap was about 90 degrees off
 > and caused me no end of blown 20 amp fuses until I corrected the timing.
It
 > was later determined that due to my odd timing the NSTs were saturating
and
 > drawing significantly higher currents than they would be normally limited.
 >
 > Note that the coil appeared to perform normally despite the dramatic
current
 > the NSTs were pulling. I was using Maxwell's and did not note any heating
of
 > the caps or primary but my runs were very very short owing to the fuses
 > blowing almost immediately; perhaps saving my caps and NSTs for another
day.
 >
 > Can you measure the line current while the coil is running? Compare that
to
 > the NST running a Jacob's ladder (non-inductive load). I bet if the
 > difference is substantial you have a SRSG phasing issue and if so maybe
this
 > is the reason for the excessively high currents on you caps.
 >
 > Dave
 >
 > =========================================
 > Dave Kyle
 > Austin, TX USA
 > Email: dave-at-kyleusa-dot-com
 >
 >
 > -----Original Message-----
 > From: Tesla list [mailto:tesla-at-pupman-dot-com]
 > Sent: Monday, March 08, 2004 9:56 PM
 > To: tesla-at-pupman-dot-com
 > Subject: Another 942 run
 >
 > Original poster: "John Richardson" <jprich-at-up-dot-net>
 >
 > Hello,
 >
 > I replaced the cap that blew yesterday, and reset all of my safety
 > gaps.  7/32 on the NST and 1/4 on the SRSG.  I think that I will set the
 > RSG a little tighter than the NST gap, because if the RSG gap doesn't
fire,
 > the NST gap will, popping the 20 amp breaker!  (Why?  Time to hook up my
 > Corcom?  Or is it because I don't have a dedicated RF ground?)  This is
 > with 300uf of PFC caps.  I did a quick alligator clip lash of of John's
 > phase controller, and with the 1/20 hp Teletype motor, about 50uf seems
the
 > best.  The voltage rise is about five volts above line voltage, or
 > 125.  Not sure if this matters.  75uf doesn't seem to make much more of a
 > difference than 50, except I get a lot more of a growl out of the
 > motor.  As I thought, the RSG phasing was pretty close before, but there
is
 > a subtle difference in output.  Zero inductance to about 25% variac travel
 > seems to be the sweetest spot, anything more and the safety gaps fire like
 > crazy.  Primary is still getting warm, but not hot like it did with the
 > last bad cap.  The dog is going ape with this thing running, so I did have
 > to keep runs short.  Caps are getting slightly warm.  Re-checked RSG
 > spacing, and the 5/32 tungstens are starting to erode.  Is this normal for
 > such a short run time?  This is my first foray into SRSGs, so I don't
 > know.  This weekend or later this week, I plan on running for an extended
 > period of time to check for tank heating and more caps popping.  I have
 > found one cap with the "sand size piece" under the first layer, per David
 > Weiss.  Will see if that one goes first.  One more thing:  Anyone running
 > their coils in a basement have some stray streamers up and hit the house
 > wiring?  It's not a good thing, but sometimes hard to avoid in close
 > quarters.  All of the incandescent bulbs in the room, maybe six or seven,
 > light up when a streamer hit the 12-2 light wiring.  Each bulb had the
 > equivalent intensity of about a 25 watt unit.  Pretty neat, albeit rather
 > unsafe.  Obvious the toroid is too small, as I can get 46-50 inchers and
 > still have multiple streamers coming off of other areas of the toroid.
 >
 > Thanks to all who are helping me.
 >
 > John Richardson
 >
 >