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Transformer build up

Hi all,

I posted this message a while ago, but havenīt recieved any answers. I do need
some help. Maybe it was too long. I shortened it a bit.

Up to know I havenīt built any largeTCīs (> 1kVA input). My current project is
about to break this "rule". (8.3" x38" secondary) 

In germany you cannot get hold of a pig (at least not under 75 to 100 kVA)  I
even tried the DB, which is the german train company: no go. NSTīs suck over
here because they are limited (by law) to 8kv and a  lousy 25mA. PTīs are
lousy, too, they are just used to measure the voltage.They have a disapation
factor of about 50 watts

My idea is to use 6 MOTS rated at 2.3kV and 700mA each (running under oil).
The only MOTīs I found being able to withstand the stress of a jacobīs ladder
are from Gardner (U.K.). I have wired up 5 of these (dry, no oil yet) with no
arc overs or corona noticable (in the dark) If I add a sixth one (different
type as I donīt have enough of the Gardner type yet) a small spark was noticed
between the iron core and the primary. But it was a pretty powerless spark
(light blue in color and not very much current flowing I would guess) . All
cores STILL have one side of the hv conneced. I am thinking of "CTing" the
setup (where the 3rd and 4th xformers meet) and earthing this point. This
should cut down the load the isolation has to carry. All transformers will be
mounted isolated from each other on heavy plastic. The whole unit (pretty
small as I stacked em 3 decks of 2 each) will be submersed in Shell Diala X. I
have a variabel inductance from an old welder (like a variac except it only
has two connections) which will be able to handle the power (altho I will
current limit it to 4 - 5kVA). I was thinking of possibly wiring each deck of
two xformers in series (2 x 230V) and the three decks in parallel because my
home has access to 400 volt 3 ph (3 x 230) mains. I would run the setup across
two phases. That way each xfomer would get 200 volts, which wouldnīt cut the
output too low but it would cut down on my input current requirements.


Comments, anyone?

Thanks

Coiler greets from germany,
Reinhard