The "average" pole pig is a 96 kva unit? I thought my 3 kva (136 lbs) was
average! Are you sure about your ratings or are you just burping a figure?
Jim,K7RDX
----- Original Message -----
From: Steve Katz <stevek@jmr.com>
To: 'Phil (VA3UX)' <phil@vaxxine.com>; <amps@contesting.com>
Sent: Thursday, December 20, 2001 4:13 PM
Subject: RE: [AMPS] HV Pole Pigs ++
>
> I'm still trying to figure why hams (including me, in my younger and
> stupider days) feel the need to use a 96 kVA transformer to power an
amateur
> amplifier. Even tubes with really big handles don't need a 96 kVA source,
> but that's what the average pole pig is.
>
> -WB2WIK/6
>
> "Each success only buys an admission ticket to a more difficult
problem." --
> Henry Kissinger
>
> > -----Original Message-----
> > From: Phil (VA3UX) [SMTP:phil@vaxxine.com]
> > Sent: Thursday, December 20, 2001 2:54 PM
> > To: amps@contesting.com
> > Subject: Re: [AMPS] HV Pole Pigs ++
> >
> >
> > Not a bad point Jack. Ultimately most of the pigs are removed from the
> > can
> > when used for amateur service. I don't know about the standards in the
US
> > but here in Canada, these pole transformers had to have enough sheet
> > insulation between winding layers to meet the electrical requirements
> > *before* they were put in oil. The oil then just added a huge
additional
> > insulation factor as well as providing the required cooling. This came
> > from
> > a conversation I had with a design engineer at Ferranti-Packard (at one
> > time, one of the largest makers of pole transformers in Canada). So at
> > least in Canada, these things can be safely run dry. However the sheet
> > insulation is still subject to the same time/temperature/aging effects
as
> > any other transformer so eventual failure is expected.
> >
> > Phil
> >
> > At 12:50 PM 12/20/2001 -0500, you wrote:
> >
> > >One thing to remember..........the oil that these transformers normally
> > >operate in is not just for cooling, it is for insulation!
> > >The oil has good dielectric properties. I used a pole pig for some
time
> > and
> > >it ultimately failed after it arced internally to the core. I had
> > removed
> > >it from the can and allowed the oil to drain off. Probably a good idea
> > to
> > >leave the transformer in the can and keep it in oil to avoid such
> > problems.
> > >Unfortunately, that makes for a rather large unit!
> > >73,
> > >Jack, W9GT
> > >----- Original Message -----
> > >From: "Geo Clute W7LFD" <gclute@attbi.com>
> > >To: <amps@contesting.com>
> > >Sent: Thursday, December 20, 2001 12:39 PM
> > >Subject: RE: [AMPS] HV Pole Pigs ++
> > >
> > >
> > > >
> > > >
> > > > I like the concept of "Dial-A-Voltage". Variac and pole peg mounted
> > > > in a 4 wheeled photo copier cabinet. Oh yes...an Edsel steering
wheel
> > > > on the Variac.
> > > >
> > > > Still looking for the Edsel.
> > > >
> > > > Geo W7LFD
> > > >
> > > >
> > > > --
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> > > >
> > >
> > >
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> >
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