Re: parallel line filters?

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <biomed-at-miseri.winnipeg.mb.ca>



Well, thank you both for your feedback.  I guess I'mm going to parallel the
two 10 amp line filters and bolt them together.  Then duct tape them on top
of the NST, alah Red Green.  :^)

I measured the line current to the NST and tesla coil with a DMM connected
inline with the incoming power after the variac.  I was suprised to to fine
out how much current this thing drew.
  My NST was high power factor 12Kv 60mA Alison model.  I figure that the
capacitive reactance of the tank capacitor 0.0214 uF cancelled out some of
the inductive reactance (which is part of the current limiting fuction of
the NST along with its shunts) of the NST so it drew more current.  Also,
this is speculation, the PFC caps built into the NST might be too large to
lower current (improve power factor) since the output of the NST is
connected to a capacitor.  If anyone has a better explaination, please
post.

Chris,  your variac is probably handleing the two NST just fine right now,
but once you add a third, the current demand will be too high and the
variac will limit the power available to you system even when it is turn up
all the way.  I run into this too, now I have a 20 amp variac to play with
instead of a flea market special.

thanks,

Shaun Epp



Date: Mon, 07 Oct 2002 07:23:48 -0600
From: "Tesla list" <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com
Subject: Re: parallel line filters?
Message-Id: <4.1.20021007072345.00a3bd30-at-pop.dnvr.qwest-dot-net>
Content-Type: text/plain; charset="us-ascii"

Original poster: "cd by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<vbprg1-at-hotmail-dot-com>

How do you determine the  amout of amps drawn during operation?
I have been using 12000v 30ma neons that are rated at 3.6 amps each
I realize they are inefficient transformers but
putting 2 in parallel for 12000v 60ma I have had no problems
pulling through a 12 amp variac...

I have recently decided to up my PS to 12000v 90ma
but am unsure weather I will have to use
a PFC motor run cap setup to pull through my 12 amp variac

Chris




----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, October 06, 2002 7:08 PM
Subject: Re: parallel line filters?


> Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<davep-at-quik-dot-com>
>
> > Original poster: "Shaun Epp by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <scepp-at-mts-dot-net>
>
> > I have a few questions regarding line filters.
>
> > My tesla coil, using a 12Kv, 60mA NST, draws about 13
>
> > amps average when running, but the line filters I have
>
> > are only good for 6, 9, and 10 amps at 250 Volts.
>
> In general the two ratings, voltage, and current, are
> independent, in this cae.
>
> > I am running my coil on 120 volts.  Could I parallel two
>
> > 10 amp line filters ( identical units)
>
> I'd expect it to work.  IIR, this was discussed
> within the last 6 months, might be something
> useful in the archives...
>
> > together for a higher current rating, would this be necessary
>
> > or would one filter do it,
>
> Might.  Iffy.  Failure modes can destroy the filter.
>
>
> > would the current split evenly between the two filter?
>
> Should, tho the split will not be exact, exact.
>
> > I'm not sure if running them at 120 volts would change the
>
> > current rating capacity on the filters or not.
>
> Good thought.  It shouldn't.  Voltage is set by
> voltage ratings of caps, etc.  Current by
> internal wiring, and wire used in inductors.
> The two are independent.
>
> > Also I run my tesla coil for short runs, could this current
>
> > rating be for continuous use?
>
> Almost certainly.
>
> > or would a higher current than rated saturate the filter and
>
> > make it ineffective?
> Certainly possible.  If the other filter is available,
>
> I'd use both...
>
>
> > Looking for an expert,
> I'm not quite an Expert, but know a bit...
>
>
> best
> dwp