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Re: is this the correct piggy?



Original poster: "David Rieben" <drieben@xxxxxxxxxxxxxxx>

Hi Aaron,

You wrote:


> Original poster: "J. Aaron Holmes" <jaholmes@xxxxxxxxxxxxxxxxxx>
>
> All that said, a number of folks (I remember
> specifically Aron and Justin of hvguy.com) have
> over-volted their 7.2kV pigs, i.e., by putting 240V
> across the 120V lugs.  This will make your 7.2kV pig
> put out 14.4kV, however it will do so only with great
> risk to your pig's health.  A friend of mine did this
> with a 14.7kV pig, achieving nearly 30kV, however
> while running his coil this way, the pig flashed over
> internally and was ruined.  Ruining hard-to-find
> components is bad enough, but what do you do with a
> half-ton paperweight? (this was a 25kVA transformer!)
>
> Regards,
> Aaron, N7OE

Now that would definitely make a grown man cry! Also,
when the primary windings of a transformer are overdriven
above their designed voltage rating to that extreme, the output
voltage of the secondary does not continue to increase in a linear
proportion to the primary's input once the core begins to
saturate. This will occur in most transformers when the input
voltage exceeds about 140% of the designed voltage rating.
With MOTs, which are made with as little iron in the core
as possible to hold down the weight and the cost, you'd better
make that about 105%! Once the core begins to saturate, any
further increase in input voltage will cause the unloaded current draw
to increase dramatically, almost in a "J" curve, but the output voltage
of the secondary will no longer continue to increase in proportion to
the increase of the input voltage. Operating in this fashion makes for
an unhappy transformer ;^(

David