Re: Cap-driven x-former?

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

Original poster: Jim Lux <jimlux-at-earthlink-dot-net> 

At 07:28 AM 6/11/2004 -0600, you wrote:
>Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net>
>Hi all,
>
>This bit of info my help
>
>Many years ago now I worked for a company that made power units for either
>GE or GEC (I don't remember which). The power units were for a photocopying
>machine.
>
>My understanding was that they were constant voltage (stabilized)
>transformers.  They had magnetic shunts and an extra secondary winding that
>was connected to a cap. The secondary voltage was about 4kV and they were
>used directly and via  doublers/triplers to supply the high voltages
>required for the charging and discharging wires of the photo drum.  They
>were big transformers as big if not bigger than an MOT. Although  now I know
>that it is unlikely they needed anywhere near the power of a MOT.  Possibly
>they needed low resistance for good regulation.  This was back in the days
>when a serious copying machine was built like a tank and approaching the
>size of a small car.
>
>One more point it was my understanding that they used the magnetic
>saturation of the main core as the stabilization effect and the cap and
>shunts improved the wave shape of the output. The shuts may also regulate
>the input current as the core saturates.  I believe because of the core
>saturation effect and hence higher losses  most constant voltage transforms
>are much larger than for a given VA rating than a regular transformer. This
>may also have been why the GE/GEC units were so big given their probable VA
>rating but I suspect it was also impart a very conservatively rated design
>and  no strong pressure to be small or light weight.
>
>Does it make sense to perform PF correction on the secondary of a
>transformer? Unusual if nothing else.
>
>Bob
>
>----- Original Message -----
>From: "Tesla list" <tesla-at-pupman-dot-com>
>To: <tesla-at-pupman-dot-com>
>Sent: Monday, June 07, 2004 6:54 PM
>Subject: Re: Cap-driven x-former?
>
>
> > Original poster: Jim Lux <jimlux-at-earthlink-dot-net>
> >
> > Check out:
> >
> > http://home.earthlink-dot-net/~jimlux/hv/xfmrex1.htm
> >
> > This is basically the same transformer. (GE part 9T68Y5021G10 )
> >


Interesting... I did actually call GE when I first got my transformers from 
C&H, and someone there (I don't recall who or where, but it took several 
days of calling one number after another) looked up the part number and 
said that they identified it as an "illumination transformer" for what 
that's worth.