Subject: PRIMARY SHORTS
From: richard.quick-at-slug-dot-org (Richard Quick)
Date: Fri, 3 Mar 1995 00:03:00 GMT
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> From: Esondrmn-at-aol-dot-com
> Subject: Primary shorts
Quoting Ed Sonderman:
ES> Well I solved the mystery last night. Remember I said that
ES> the discharges/shorts always seemed to appear in the upper
ES> part of the primary - like around turn 14? Turn 14 is
ES> arcing to the strike rail.
Yup! That is just typical of a minor little bug that you will
find on a new coil system. As you increase power levels you
will undoubtly uncover more of them, and like this one, they are
almost all minor adjustments.
ES> I designed the primary supports with the hole pattern to
ES> hold the copper tubing shifted up on each support as you go
ES> around the coil. This makes the last one half turn or so
ES> closer to the top of the coil form. Then when I added the
ES> supports for the strike rail I positioned it a fixed amount
ES> above the primary coil form. In some places I have 1.0"
ES> clearance and it narrows down to .50". I obviously need to
ES> raise the strike rail to gain more clearance. Is 1.0"
ES> clearance all the way around enough?
One inch clearance is what I use, and rarely have I had a jump
from the primary to the grounded rail.
ES> I have another question. When I shut the coil off after
ES> running for several minutes, I can draw a small spark from
ES> the system RF ground to my hand - up to 20 minutes later. I
ES> don't understand this. All connections to the AC line are
Ahh, another interesting function of Tesla systems. As much as I
post on this subject, it is hard to make people understand until
they actually experiment. The ground is not at ground potential
when a Tesla coil is in use: the ground is hot. If you doubt the
validity of this statement, ground a lone secondary coil that
resonates at your system frequency to the system ground and fire.
The bare secondary will resonate to good spark on the ground
This is probably not the reson behind your drawing a spark
though. Most likely it is an electrostatic phenomena. When
coils are firing, electostatics (static electricity) behave
very strangely. I have seen coils give static shocks, after
shocks, after shocks; long after they were turned off and even
completely removed from the system! Even after they had been
grounded to system ground several times!
ES> I would like to wet down the ground rod area but the ground
ES> is frozen right now. Ed Sonderman
I don't know if it will help, but see the post I sent on
connecting plastic pipe sewer systems.
... If all else fails... Throw another megavolt across it!
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