Re: [TCML] Terry Filter for a pig?

["DC Cox" <resonance@xxxxxxxxxxxx>]

We use an air core inductor and a group of twelve -- 600 Ohm resistors
connected in parallel, along with a spark gap to
do our pole xmfr protective circuit.

If anyone emails me AFTER Tesla Fest 2008 is over I can forward the circuit
to them.

Dr. Resonance




On Tue, Sep 2, 2008 at 7:17 PM, <FIFTYGUY@xxxxxxx> wrote:

>
>
> In a message dated 9/2/08 4:13:09 P.M. Eastern Daylight Time,
> Gary.Lau@xxxxxx writes:
>
> >Terry filters are usually used for NST's with mid-point grounded
>  secondary
> coils, and this is why >there are basically two of everything -  one filter
> for each side.  But with a pole pig, wouldn't you tie
> >one of the HV bushings to RF ground?  I'm not sure why there  needs to be
> two complete filters (as
> >shown in the photo link) as with  NST's.
>
>
>    Sure, I could ground one bushing of my pig. But to  where? RF ground?
> Fine, I wouldn't have to worry so much about transients  at *that* end of
> the HV
> winding - but the transients at the *other* bushing  might be twice as bad,
> and then added to the extra 8kV over  ground that bushing would now be at!
> FWIW,
> my pig is Y/Delta rated.
>    And as far as the complexity or number of  components - well, I'd still
> need *one* arrestor at full voltage, instead of two  at half voltage. I'd
> need
> a different cap configuration, but  essentially twice the series voltage
> rating at the same capacitance to keep  the same cutoff frequency. So the
> cap
> portion would end up more expensive.  The resistors would have to handle
> twice as
> much current, thus quadrupling their  power dissipation (wasted energy).
> I've
> got power resistors of all  sizes coming out of my ears, so for me that's
> not a
> cost issue.
>    And overall the current  configuration keeps the filter
> compartmentalized
> and modular for damage  control if something goes wrong.
>    Nope, I think I like my nice symmetrical setup,  just the way Terry
> would
> have liked it. :)
>
> -Phil LaBudde
>
> Center for the Advanced Study of Ballistic  Improbabilities
>
>
>
> **************It's only a deal if it's where you want to go. Find your
> travel
> deal here.
> (http://information.travel.aol.com/deals?ncid=aoltrv00050000000047)
> _______________________________________________
> Tesla mailing list
> Tesla@xxxxxxxxxxxxxx
> http://www.pupman.com/mailman/listinfo/tesla
>
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla