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More MOT supply questions



Original poster: "Michael Strube by way of Terry Fritz <twftesla-at-qwest-dot-net>" <mjstrube-at-earthlink-dot-net>

Thanks to all who weighed in on the crimp-solder-quick connect issue.
Very helpful advice--amazing how such a seemingly simple question can
have so many facets to it. 

I have another question. I am now selecting the MOTs that will be part
of the 4-pack that I am building. I have 30 or so MOTs around my shop to
choose from and not a pair that are duplicates (not a rare situation I
understand). All are of the 2200 volt variety. I know that the outer
MOTs will need to hold off the higher-than-usual voltage and I've seen
the recommendation to choose MOTs (usually older ones) that have the
greatest winding-to-core spacing. I have a small number that would fit
that bill just fine. But, they have different primary and secondary
inductances. For example, one has a primary inductance of 46mH and a
secondary inductance of 13H. Another has a primary inductance of 24mH
and a secondary inductance of 7H. On the other hand, among the numerous
small-spacing MOTs that I have, I can match up several pairs so that
they have very similar inductances.

So, the question: Is it better to have the outer MOT pair matched on
inductances and not worry about the winding-to-core spacing, or, to make
sure the winding-to-core spacing is large but the inductances
mismatched? Can't have both at the moment and given the number of MOTs I
have now and their wide variation, I'm not hopeful that further
scrounging would allow matching inductances AND having large spacing.
Let me add that the MOTs will be under oil (I'll occasionally use a
level shifter design for this supply), so perhaps the spacing is less of
an issue in my case.

Thanks in advance for any help.

Mike