Re: New coiler, also in search of 15kv

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: DRIEBEN@xxxxxxxxxxxxxxx 

Chris,

That would be (G)round (F)ault (I)nterruptor.
All of the newer NSTs must be equipped with this
safety feature, according to UL. This feau-
ture quickly shuts down the output high voltage
if it detects that there is any leakage to ground.
To my understanding, all of the feedback of a Tes-
la coil circuit also "tricks" it into thinking that
there is a ground fault even though most NST powered
coils run with both input legs "hot". If you have a
GFI'd transformer, you can easily short both of the
"hot" leads from the HV output bushings to each other
with no problem but the instant that you try to short
one of the HV bushing leads to the case, it will im-
mediately trip the breaker button and shut it down.
You have to push the button back in to reset it, much
like the thermal overload protection on electric motors.
Like I said, from my understanding, trying to run a Tes-
la circuit with this type of transformer proves futile
unless you can defeat the GFI feature.

If yours is an older one, then you shouldn't have to
worry about the GFI issue, since GFI'd NSTs have only
been out the last couple of years. As I previously
stated, it looks like you got yourself a good deal.


David Rieben

----- Original Message -----
From: Tesla list <tesla@xxxxxxxxxx>
Date: Monday, May 8, 2006 11:20 am
Subject: Re: New coiler, also in search of 15kv
To: tesla@xxxxxxxxxx

> Original poster: "Chris Farmer" <cfarmer@xxxxxxxxxxxxxxx>
>
> Dave,
>
> I'm not sure about the GFI thing, what does that stand for?  The
> one
> I got looks relitively older and makes a pritty good jacobs ladder
> so
> I figure it would probably work for a coil... interesting though
> to
> hear that I got such a good deal on it though.
>
> ~Chris Farmer
>
> ----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
> To: <tesla@xxxxxxxxxx>
> Sent: Sunday, May 07, 2006 5:41 PM
> Subject: Re: New coiler, also in search of 15kv
>
>
> >Original poster: "David Rieben" <drieben@xxxxxxxxxxxxxxx>
> >
> >Chris,
> >
> >Well, you did well ;^) because there's usually considerable
> >competition for the larger NSTs, especially the 15 kV ones
> >and 15/60's do in fact usually end up around the $100 mark
> >by the close of the auction, thanks to the last minute (literally)
> >flurry of ebay snipers. All that I can say about your aquisition
> >is that you obviously caught the competition "napping" and
> >that you should consider yourself lucky. BTW, would this
> >transformer of yours happen to be the newer GFI type?
> >Coilers don't go as hot for the GFI type because the GFI
> >feature renders them fairly useless for Tesla service unless
> >you can figure out how to defeat the internal GFI circuitry.
> >
> >David Rieben
>
>
>