[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [TCML] Can i use an NST as ballast ?



Hi Andreas,

Assuming that your new HV "plate" transformer has much less leakage inductance than your ballast NST(s), you can estimate the output current as follows:

Your NST:
Rnst = Turns Ratio of your NST = 8000/120 ~ 67
Inst = 60 mA (short circuit)
Ipri = Inst*Rnst = 67 * 0.060 = 4 Amps

Plate Transformer:
Rplt = Turns ratio of your plate transformer = 14300/120 ~ 119
Since the NST and plate transformer primaries are connected in series, they see the same current, so:

Isec (plate) = Ipri/Rplt = 34 mA (short circuit current from your NST-ballasted 14.3 kV transformer)

If you use more NST's connected in parallel in your ballast bank, compute the turns ratios and short circuit primary currents for each one and then add them all up for the total. You can use any mix of NST output voltages in your NST bank since each one will be short circuited. You'll need to figure the turns ratio for each NST and primary current separately when faceplate output voltages are different.

Bert
--
********************************************************************
We specialize in UNIQUE items: coins shrunk by ultra-strong magnetic
fields, Captured Lightning Lichtenberg figure sculptures, and scarce
technical Books. Please visit us at http://www.capturedlightning.com
********************************************************************

Andreas wrote:
Thanks,

In a ballpark what current can i expect from the larger HV transformer
if i hook up my NST to the primary for ballast ?

--------------------------------------------------
From: "Teslalabor" <teslalabor@xxxxxxxxxxx>
Sent: Monday, October 25, 2010 6:43 PM
To: "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
Subject: Re: [TCML] Can i use an NST as ballast ?

Yes, you can use shorted NST's for current limiting. The more power
you need, the more shorted NSTs in parallel.

----- Original Message ----- From: "Andreas" <andreasho@xxxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Monday, October 25, 2010 5:42 PM
Subject: [TCML] Can i use an NST as ballast ?


Hi,

I got this HV transformer i want to try out but it needs some current
limiting.

Left in the picture.

http://i1212.photobucket.com/albums/cc446/tesladude/trans1.jpg

Specs:

55pounds
260vin
14.3Kvout
1200VA

DCresistance:
Primary: 0.2 ohm
Secondary: 882 ohm

The extra wirering is for cable sheilds and temp.

Could my 8Kv 60ma NST work as an ballast and what would the current be?
I probably need to know the inductances for that ?
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla

_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla

_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla




_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla