Re: Primary Ballasts for Pole Pigs

To: tesla-at-pupman-dot-com
Subject: Re: Primary Ballasts for Pole Pigs
From: Richard Hull <hullr-at-whitlock-dot-com>
Date: Tue, 14 Mar 2000 20:33:12 -0800

Tesla List wrote:
> 
> >From brad-at-greenepa-dot-netThu Nov 21 14:43:24 1996
> Date: Thu, 21 Nov 1996 16:00:07 -0500
> From: iLLuSioN <brad-at-greenepa-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: Re: Primary Ballasts for Pole Pigs
> 
> Hello all,
> 
>    I have a question that I was wondering if anyone could answer. I am a
> lighting tech at a few theatres, and I came across some older 6.6 KW
> resistance dimmers... Would they be of any use for ballasting the primaries
> of pole pigs? I am planning to eventually build a coil with a 10 KW pole
> transformer... Any comments?
> 
> Brad

Brad,

I find that resisitance in the primary circuit of the pole pig is a must 
have item.  However, I tend to mix it with a bit of inductance.  This 
mixture seems to allow perfect balancing of the system while in 
operation.

I would strongly recommend against the use of inductive or resistive 
balllasts only!  The resisitve ballast alone will dissapate too much 
valuable energy and the inductive ballast will be far too finicky to 
adjust to run with great smoothness.

I have found that for my system I require about .3-.5 ohms of resistance 
and about 3mh of inducatnce. These should be placed in series with the 
low voltage side of the pole pig and the power source.  I can vary both 
values to allow for new capaciotr loading in the tank and or replacement 
transformers.

Richard Hull, TCBOR