Re: 120 or 240 VAC? to power 4 15KV 30ma NST's

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "David Speck by way of Terry Fritz <teslalist-at-qwest-dot-net>" <dave-at-davidspeckmd-dot-org>

Gerry,
Personally, I would tun the transformer farm off 220 volt center tapped to 
neutral, with a dual ganged 110V 1kW minimum per section variac. This 
allows you to use smaller gauge wire,  switches, and relays.  Of course, it 
would be better to buy a heavier variac if you can afford it -- you can be 
sure that if 2kW is good, 5 kW will be better.  A balanced arrangement will 
better tolerate any mismatches in the transformer characteristics

I would definitely not run a setup of this size without a variac to bring 
it up slowly.

HTH,
Dave

Tesla list wrote:

>I want to power four 15KV 30ma NST's (all with 120 VAC inputs).  I could 
>put them all on a 120 VAC line and get a big 120 to 120 variac or put two 
>on one phase and two on the other phase of 240 VAC line.
>The latter configuration would require a 240 to 240 VAC variac but each 
>phase would be half the line current of the first configuration.
>I'm planning on adding a dedicated power line in the garage for this 
>purpose and can breaker it appropriately.
>
>Any recommendations???   Also for the 2 KVA NST load (with or without 
>power correction) how much larger a variac (in KVA) should one get???
>
>Should a 2KVA system be brought up gradually (with a variac) or can one 
>just flip the switch (and not use a variac).  Assuming that any RSG is 
>spun up first.
>
>Gerry R
>Ft Collins, CO
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