Re: Ballasting MOTs

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

Original poster: "Christoph Bohr by way of Terry Fritz <teslalist-at-qwest-dot-net>" <cb-at-luebke-lands.de>

Hi!

I encountered similar problems, but no reason to fall into despair ;-)

If I assume you really meant your primary leads are shorted I have to
conclude you are putting the sencodary in series with the mot-pack output.
Although this is possible I would not recommend to do that.
The long wire in the secondary winding causes pretty high losses at the
currents involved, so heating up might really be a problem, things have to
go terrible wrong before you burn a tranny under oil ( in fact usually you
will have to boil all the oil off before anything really burns ). Maybe your
oil isn't dedicated transformer oil....?
Ballasting with MO-caps is really the way to go if you get your hands on
some caps. This will give you a quite tame supply with the benefit of higher
output voltage compared to indictive ballasting.

I personaly use 2 bigger MOT's in parallel on the primary side for about
5KVA, just like Scot advised you, too.
Although my ballasting MOT's are pretty different from each other I never
had problems, but it's probably
advisable to use two identical units.

I found with my TC the ballasting is not too critical so any ballasting will
be good for some initial testing, but an unbalasted MOT will fry anything
thats in it's way ;-) I can only run an jacobs ladder unballasted when I
connect directly to our 240V/63AMPS Mains in the basement...and this really
makes the street light dim for a moment )
Scot's idea of a dedicated, variable ballast would give you the easiest way
to find the optimum value... I will build one, too if time permits.

good luck and give that cap-thing another try....it can work really great.
( what problems did you have with caps ? )

Sincerely

Christoph Bohr