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Re: 10kva pole pig needed with 29kv primary



Original poster: BunnyKiller <bunnikillr@xxxxxxx>

Hey David...

yupperz Im following this thread..

When placing transformers in either paralell or series ( similar to batteries for voltage applications) you get additive properties in either voltage or amperage depending on the setup.
Lets consider that we are using just 2 equal types of transformers.
In paralell, you get the same voltage ( considering the transformers are "identical") with twice the amperage draw and amperage out put capacity.
2 @ 14.4 KV  @ 10KVA   yields 14.4KV @ 20KVA
In Series, you get twice the voltage output but the system will output ( in amps) what a single transformer is rated for without damage..
this setup yields 28.8KV @ 10KVA.

If one tries to series 2 transformers of equal voltage but different KVA, the system is limited to the lower KVA unit....

maybe this example will work... 10 100 ohm resistors in series have additive ohms but since they are all rated for 1/4W we now have a "larger ohm value" (1000 ohm) resistor but still only capable of 1/4W current the transformers can be considered "resistors" in the same sense....

and for those new to the list..
the reason Im getting 30+KV out of this setup is because I have the variacs wired for 280 vac total output, which gives the piggie that extra boost...

Gerry is correct... I dont have the "center tap/connection point between the 2 transformers" grounded... maybe I should consider doing so....

hope this helped..

Scot D



Tesla list wrote:

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

Hi Gerry,

>From what I gathered, Scot is running his pigs in a "piggy-back"
configuration - the second pig's input is riding on the 14.4 kV
output of the first one, leaving the "zero-volt" side of the second
pig "floating" at 14.4 kV, just as I suggested in my first posting
on this thread. That would definitely account for the corona
'hissing" coming from inside the pig. BTW, Scot also mentioned
that he took the guts of (2) 14.4 kV pigs and placed them both
in one pig tank. That would make for one really stuffed and heavy
piggie ;^) and would also explain the tight internal clearances for
the ~30 kV. If wired as you're suggesting, then each pig would
indeed only see its rated 14.4 kV in relation to ground and there
would be little if any internal "hissing" ;^)

BTW, Scot, if you're following this, you stated in your previous
post that your double 10 kV pig was good for 30 kV at 10 kVA.
Wouldn't the (2) 10 kVA pigs now be good for 20 kVA? They
would put out twice the voltage as one pig with the same amper-
age if in series.

David Rieben