Re: more RFI filter questions

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

Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> 

Hi Steve,

The direction of hook up:  depends on the design.  Most filters I've dealt
with are intended to keep stuff from getting out of a box and onto the line
and as such have an asymetry to their design.   I would not hook them up
backwards.

Parallel connections:  depends on what you mean.  If your pig is powered
from 120, then parallel would mean truely parallel and I would presume you
are trying to get higher amp capability.  The filtering effectiveness would
be reduced.  If your pig is powered from 240 and these are single line
filters, you could use one for each line and I think this would work.   If
the filters are intended to filter the dual line associated with 240V
operation, then putting two truly in parallel would again reduce the
filter's effectiveness.   As to frequency response of the filter, the TC
resonant frequency is of lesser concern than the higher harmonic frequencies
and stuff generated when the spark gap fires due to space charge
discharging.

Grounding:  the case of the filter should be connected to mains safety
ground.  This is the reference (with respect to) that you are trying to
clean the mains.


 > Original poster: "steve" <steve_vance-at-cablelynx-dot-com>
 >
 > Hi List,
 >
 > I have bought four Corcom 30vsk6 filters off of  ebay. They are rated 30A
 > 250V. I would like to use them on my 5KVA pig powered coil. I have
searched
 > the archives for answers to my questions but all I can find out is that
 > there is a lot of disagreement on the subject of connecting RFI filters.
 > So....Here we go again.  Do they work better if they are hooked up
 > backwards? Will placing two filters in parallel lower the attenuation to a
 > more useful level for tesla coil frequencies? Do I ground the filter cases
 > to the mains ground or do I use the coil's RF ground?
 >
 > Thanks,
 > Steve Vance
 >
 >