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Re: buying a pole pig



Original poster: Ed Phillips <evp@xxxxxxxxxxx>


$50 for a pig ain't bad.  3.5' tall sounds *real* big,
though.  There are some tall-'n'-slim pigs out there,
though.  I've got a 15kVA unit that's about 3' tall,
but I've also got a 25kVA unit that's scarcely 2'
tall, so you never know.  I'll put in my guess at *at
least* 25kVA, maybe 37.5 or 50.  Let us know! :-)

Hard to dynamically test a pig without some big juice.
Checking continuity is a good idea, though.  The LV
windings ought to look almost like a short (less than
one ohm), but the high side will probably have a few
kOhms in it.

Also, no matter the kVA rating, if it's less than
7200V I'd leave it alone.

Regards,
Aaron, N7OE"

That sounds like far too much secondary resistance. Suppose it's a 25 kVa, 14 kV unit. The secondary current at full load would be something like 1.8 amps. If the i^2R loss was 1% of the total power (can't see it being much more than that) or 250 watts, the corresponding secondary resistace would be around 78 ohms. For a 220V primary the corresponding maximum resistance would be about 0.02 ohms if I haven't slipped a decimal point or two.

Ed