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Re: Building your own HV transformer
Hi,
I have some formulas on my web page that I used to
make my transformer. Core thickness mainly. The rest
is really variable and up to the designer. Heres the addr.
http://members.aol-dot-com/tesla00/hbt.htm
Concerning eddy losses: I use spools of 12 gawg wire
to ballast my transformer. By placing a solid steel rod
in the middle of one of the spools the XL goes up by a
factor of ~2.4 Running 20a through this ballast for 1
minute will heat the iron rod up enough to melt the
plastic spool. I didn't think eddy currents would be
so bad the first time I tried this and I almost received a
bad burn.
Truthfully the best way to figure out how many volts per turn your core can
take is to wind a simple coil and test for saturation. This will tell you how
few primary turns you can get away with. Your core is only power limited by
heat.
Later,
Erik Schulz <- Gradient
http://members.aol-dot-com/tesla00/
CS major - so lay off of my grammar :)
> Anyway, does anyone have some simple (or not so simple) formulas to
> approximate core thickness (laminated silicon steel), primary windings
> needed
> to not saturate the core at the wanted VA level, etc. I've found a couple
> places on the net but the results were so wildly in disagreement that I
feel
> I need a third (or fourth) opinion. For example, I think I can get a cheap,
> used 3-phase transformer from the junkyard which has about 3" by 3" core
> thickness. How much abuse would this take? And I also already have a
smaller
> typical EI-type laminated core, which has a thickness of about 1" by 3".
>