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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> > > Problems: owner-amps@contesting.com
> > >
> >
> >
> >--
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>
>
>
> --
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