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Re: nst current limiting




> what would the power requirements be for 9kv30ma and 15kv30ma?like put me in 
> the ball park.

Power requirements? You mean how much those NSTs eat?
You can first get the VA by multiplying volts with amps, i.e.

9 kV 30mA => 270VA
15kV 30mA => 450VA

So the current they take on the mains side is 
I = 270VA / U and I = 450VA / U,
and for 110V mains: 
I = 2.45A and I = 4.09A

The NSTs have a cos(phi) rating of 0.55 generally (or always?),
so input real power is then 270VA*0.55 = 149 Watt, and 247.5 Watt for the 
other.

Both are not even close to an ordinary hair dryer... ;o)
(but don't think the NSTs are safer than a hair dryer!)

Btw, if you use a completely matching power factor correction cap in
parallel with the mains side of the NSTs, you could get your input current
down to about half or less, without affecting output power.

Was this what you were asking?

PS: Maybe PFC could also halve your electricity bill for running the TC.
Those meters with the rotating disks measure current (I think) and not
real input power, so reducing current reduces your bill (minimally).

greetz,
Jan