Re: Pig questions

To: tesla-at-poodle.pupman-dot-com
Subject: Re: Pig questions
From: Tesla List <tesla-at-stic-dot-net>
Date: Sun, 30 Mar 1997 07:59:45 -0600
Approved: tesla-at-stic-dot-net
Subject: 
           Re: Pig questions
      Date: 
           Sun, 30 Mar 1997 03:21:37 -0600
      From: 
           Chuck Curran <ccurran-at-execpc-dot-com>
        To: 
           Tesla List <tesla-at-pupman-dot-com>
References: 
           1


Tesla List wrote:
> 
> Subject:
>         Re: Pig questions
>   Date:
>         Sat, 29 Mar 1997 12:19:13 -0500
>   From:
>         "Lord Talimar" <lordtali-at-mill.tds-dot-net>
>     To:
>         "Tesla List" <tesla-at-pupman-dot-com>
> 
> how does one use an arc welder for a current limiter?
> 
> LT


LT:
        The Arc Welder is used for current limiting by connecting it's
240 VAC
primary in series with your pole pig primary.  The low voltage output
leads of the Arc welder are then shorted together.  Now, when your
system draws power throught he spark gap on the high voltage side of the
pig, you will realize an inductive current limiting, Ldi/dt, that
prevents the Tesla system from drawing a total short circuit current
draw.  Without the welder in place, you will here lots of clicks, as
circuit breakers rapidly pop all over the place!  The most commonly used
welders also have an adjustable current output lever or wheel, to allow
the arc current to be adjusted from for example, 40-250 amps.  This
feature allows you to start off at a  low setting while getting your
system in tune and then progressing to bigher power levels by moving the
arc current adjustment upt closer to the maximum.
        Another technique normally employed is to also either parallel
or
series several high current, high power resistance elements with the
welder.  I use electric stove elements in parallel with the welder. 
I've seen a very clear and dramatic change in spark output when trying
either two elements in series or parallel with each other, then that in
parallel with the welder.  My system gives the best spark with one 2200
watt stove element in parallel with the welder.  This is one of the big
draw backs to the pole pig system, first you buy the pig and then the
welder and $500.00 is gone.  Then there's the high power auto
transformers to drive the package, a good one being the Superior
Powerstat type 1256D, which you might be able to pick up for $150-$300
used--new they are about $800.  Decent metering, EMI filtering, relays
and a few other things, all which should move you to find the list of
dates for the local Ham Fests in your area.  Ham Fests are a good source
for used parts that can keep cost to an acceptable level.  Have fun
deciding what to do!

Chuck Curran
Cedarburg, WI