Re: ~Variac question

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

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

For testing purposes... although a variac is nice, you can get by with some
lightbulbs in series or parallel.

A 100W lightbulb limits the current to around .5 to 1 amp. (Cold resistance
is a lot less than hot, so it's hard to predict).   A 300W halogen bulb
will limit the current to around 3-5 amps (bulb life in this application is
VERY short, by the way, because it doesn't get hot enough for the halogen
to do its thing).

I have a standard J box with a cord and plug, a receptacle, and a regular
old porcelain socket on the top into which I can screw a variety of bulbs.
Very handy for that first smoke test...  You can get bulbs all the way down
to 7 watts and up to around 200 Watts in the usual screw base.  Not only
does it limit the current if your device is shorted, but it lights up to
tell you.



Tesla list wrote:
> 
> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
> 
> Re: ~Variac question
> 
> Hi Jaime,
> 
> 15000 volts x 60m amps = 900 watts = 0.9 KVA = 900 VA
> 
> If you can get them used, ebay, junk yard...  You save the cost of about $200
> for a brand new one.  There are some asian versions sold by Jameco and I
think
> Radio Shack for about $100 now.
> 
> I checked and Radio Shack's is about $200....
> 
> Jameco's catalog has #169658  2000VA for $119.95 (before shipping the 30
> pounds).  I had a different version of the "cheap ones" and it worked fine.
> Not as good or would last as long as my Powerstats, but they do work.
> 
> Check around and maybe ask the list for them.  I just gave away twelve 20 amp
> 240 VAC variacs for free cause I got tired of looking at them ;-))
> 
> Cheers,
> 
>         Terry
> 
> At 06:06 PM 2/15/2002 -0500, you wrote:
> >
> > WHat size would I need for a 15kV 60 mA NST
> >
> > .....and where do I get something like this?
> >
> > Thanks,
> > Jaime