Re: Slide-choke construction

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

Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 




Another interesting advantage using a large sliding choke offers is that it
can eliminate the costly variac altogether!

With the core in full, only a few Amps (magnetizing currents) are drawn by
the HV xmfr so while it remains at the full 240 VAC it doesn't get any
appreciable current so nothing happens.  The xmfr can't supply enough
current to charge the caps.

As the core is slowly withdrawn the current begins climbing.  You can set
the current point at any current level you desire and do not need a variac
at all.

It's an interesting concept and works very well.  We use this idea to
eliminate variacs in all of our larger systems.

Dr. Resonance



 >
 > this has nothing to do with the steel rod idea but it may help by giving
you
 > a ballpark figure to work with. My current limiter was made by winding
about
 > 50-60 turns of 2.5 square millimeter house wire (rated at 25amps
continous)
 > onto an old MOT core this limits to current in my MOT bank to about
35amps.
 > In terms of linkage http://tesla.reidconsulting-dot-com.au/tesla.html details
 > exactly what you're building
 > and http://www.richieburnett.co.uk/ballast.html has a lot of info on
 > ballasting.
 > Hope this is of some help
 > Pat
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Thursday, May 13, 2004 2:10 AM
 > Subject: Slide-choke construction
 >
 >
 >  > Original poster: "Erik Byng" <ebyng-at-knox.edu>
 >  >
 >  > Hey list:
 >  > A while back, in a post titled "the amazing variable choke," someone
 >  > mentioned that they'd build themselves a slide choke, running a bundle
of
 >  > epoxied steel rods through a pvc form with the coil wound on it.  I'm
now
 >  > thinking of building one myself, but the dimensions I'm a little shakey
 > on.
 >  > I have a +/-300ft roll of 10ga thhn which seems up to the challange,
but
 >  > should it be wound with very few layers on a long form, or many layers
on
 > a
 >  > short form?  I would think that to get the most out of the rod's
travel,
 > it
 >  > would have to be wound long..  5 or so coil layers over ten inches of
 > travel
 >  > sound decent?
 >  >
 >  > Erik
 >  >
 >  >
 >  > --
 >  >
 >  >
 >  >
 >
 >
 >