10KV RMS -at- 300MA transformer

            10KV RMS -at- 300MA transformer
            Wed, 02 Apr 1997 10:53:55 -0800
            Skip Greiner <sgreiner-at-wwnet-dot-com>
            Greiner, Ltd.
            tesla list <tesla-at-pupman-dot-com>

Hi everyone and especially those who purchased these transformers

I have bitten the bullet. I have made the decision to go ahead and
modify my two transformers and operate them at their full 5000v rating
using the resonator cap in series anti parallel.

Last night I started to take the first one apart. It took almost 1 hour
to get thru to the HV terminals. I found two potential (pun intended)
problems, maybe three. First, the varnish impregnation in my units is
still very soft, almost sticky. Before I fire these beasts up for real,
I may let them cook for a few days with some kind of load to see if this
stuff will cure. The next problem is voids down inside. There are air
spaces and these are probably able to breath and suck in humid air.
Eventually they might be prone to cause arc-over. I doubt that running
these things in oil will do much to stop this problem. I plan to open as
much of the covering around the HV winding as I can and flood it with
corona dope. The next problem may be in the soldering of the HV winding
leads to the the terminals. I found burned spots around the terminals
from the soldering iron which might lead to carbon tracking. I am
removing he terminals anyway and the burned spots go with them. The last
item has been mentioned before. That of the lead from the inside of the
secondary. It only has a very thin piece of spaghetti over it, which is
totally inadequate for our purposes. I am adding a major amount of
additional insulation and a generous amount of corona dope. I will also
be adding the safety gaps to each transformer as previously suggested.

I then plan to run the anti paralleled transformers on a small TC and
then progressively larger ones until I get to their max power or burn
them out.

Fr. MaGahee: At one time you mentioned that you thought these
transformers have large wire in the secondaries. Do you know what size
it is?

Well, that's it for now. Will report further as I get into this