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Re: hv connections



Hello all (esp. Fucian & Christopher),

(snipped here and there)
My comments interspersed.

> Original Poster: "Christopher Boden" <chrisboden-at-hotmail-dot-com>
> was looking at me like I was a wus when I would VERY gently
>hold the wire.

Well it doesnīt make a whole lot of difference if you hold it (very)
gently or not. IF the insulation breaks down, your muscles WILL
contract and you wonīt be able to let go and it doesnīt make a
darn of a difference HOW you hold the cable. Best not to try
this. BTW, 15kV is the rated voltage of the cable (and on a 15kV
neon you are only using half of itīs rated voltage above ground
potential), NOT itīs breakdown voltage. That will be at least
2-3x the rated value.

> 4AWG "Monstor Cable" used for car audio work.

Well, unless you get that stuff for free or much cheaper than
retail price, welding cable will be A LOT cheaper. That audio
stuff (like Monster Cable) has lots of *hog wash* (OFC, etc,
etc), which will do NOTHING to improve your coilīs output.

> We use Panduit or Stake-On wire connectors, always terminate your
>connections in a crimp connector. Never use plain old bare wire
>wrapped around a bolt. It's icky, rather unreliable, and in my opinion,
>unsafe. Crimp the wire, then give it a firm tug, if it fails the
>Tug-Test, cut it, and redo it. You'll get it right.

Sorry, but I wonīt agree on this one. Do NOT just crimp your
connections. Rather SOLDER them. It only takes an extra minute
and it is MUCH more reliable than crimping alone. You would be
surprised as to what resistance a crimp-alone connection can have
(or get after a while).

> Unless it specifically says so on the wire, almost ALL wire is rated
>for 600 Volts. The reason for this magical number is that's the

This isnīt quite true either. NO way, will normal hook-up wire
withstand 600V (in a safe-to-handle way). House wiring in the U.S.
has a UL rated value of 600V. Normal (small gauge) wire does NOT
(and it has no *other* voltage markings, either).

> amperages, once they touch an arc can be sustained indefinately.

Actually, it depends on their duty cycle ;o)

> Some guys, especially the pros out there don't even use wire, they use
> copper ribbon, when we evolve to a pig system we will use it as well.
> the REALLY big coils use pipe, look up a coil called Electrum and you
>will see the primary connects are made from large copper pipe.

This has to do with the skin effect. It makes NO difference if you use
a big round conductor or a flat ribbon conductor. The "inner" part of
your round conductor will see little or no current flow, but it wonīt
perform any worse.

(Low voltage ground)
> here isn't terribly important, just a good tight connection. anthing
>from 10 to 18AWG is fine.

I canīt really let this stand that way either. It depends on what
xformer you are using. For a low to mid powered coil, okay, but
if you run a 25kVA pole pig that ground connection had BETTER
be heavy and able to withstand a mainīs short circuit (for whatever
reason this might happen) w/o melting.

> has to connect to a real ground. Get a couple copper ground rods
>(about $5 each) at a home improvement strore and drive them in
>the ground next to your house. If you're lucky, keep an eye out for
>your local utility trucks and

I have said this at least 10 times before: FORGET copper pipe or rod.
It is WAY too soft to get into sandy or rocky ground, esp. STRAIGHT.
Instead, use some galvanized T-iron. You can smack this into ANY
kind of ground with a hammer and it will NOT bend. IF you do drive
them in yourself, be 1000% SURE you know EXACTLY where gas
pipes, telephone and electrical conduits are, BEFORE you pound it into
the ground. If you hit any one of those, you WILL wish you had never
heard of a Tesla coil (=>$$$) in your life.

> Any LARGE diameter wire or cable will work, just make it as big as
>you can get and make the connections tight.

Hmm, I can get some pretty large braided wire (good cross sectional
area), but it would make an awful grounding system, due to the losses
this kind of wire has.


Coiler greets from Germany,
Reinhard