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

Re: [TCML] Consensus on HV cable




Not to pile on here, but just to do some of the calculations for the original question:

- For a Pole Pig of 14400V output, and 1.0uf tank cap, 60Hz Ichg= 377*1x10^-6*14400 = 5.43A

- NEC Table 310-16 suggests ampacity for 10Ga AWG between 30 -40A depending on temp, 60-90 C.

- Inner conductor diameter of RG8/U coax is, depending on type, is between 0.103" to 0.108" copper, stranded or solid, with insulating material of foam polyethylene or teflon.

- Diameter of solid 10Ga AWG copper is 0.102"

- Therefore, using the center conductor only of a length of RG8/U is feasible for a 1uf Tank primary + 14400V pole pig , taking only current into account.

Am I missing something in that brief analysis?

However, I wonder if the group could comment - does it matter if the core insulating material is foam-polyethylene, or teflon? Should one consider shorting the shield to the center conductor to avoid creating some sort of distributed capacitive transmission line (though at 60hz, probably not so much of an issue)?

Has anyone actually done this?

Thanks in advance,

Joe




On 9/14/2010 5:46 AM, David Sharpe wrote:
David

What is output voltage of pole pig?
What is size of tank capacitor?

Ichg ~ w * C * E  (w= 2*pi*f; 377);  C farads, E volts, Ichg amps
Ichg is approximate steady state VAR current

  Would size wire to support minimum 2X that value
  (see NEC table 310-16 for typical conductor
   ampacities).

Typical #16 is good for 7.5A continuous which at
12kV is nearly 90kVA delivery to load; insulation
to support applied voltage.

Regards

On Mon, Sep 13, 2010 at 11:49 PM, David Speck<Dave@xxxxxxxxxxxxxxxx>  wrote:
  Esteemed list:

Is there any consensus on the optimum gauge and insulation of the cable that
goes from the HV output terminals of a 10 KVA pole pig to the RSG and tank
cap of a 12" x 48" Coil?

I seem to recall that the inner conductor of RG-8 coax with solid
polyethylene jacket and without the shield was the preferred material.

Anyone found anything better?

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




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