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Re: PCB test kits....5KW



Original poster: "J. Aaron Holmes" <jaholmes@xxxxxxxxxxxxxxxxxx>

They sound great to me!  I imagine the 3kVA one,
despite similar size, is probably a good deal lighter.
 Anyway, just 'cause 5kVA means 45A at 110V (assuming
unity power factor--not often achieved for a Tesla
coil!) you don't need to feed it all those amps if you
don't want to.  That's what adjustable ballast
inductors and resistors are for.  I've used my 15kVA
transformer to drive 1-2kVA coils no problem.  It
loves to do that :-)

PCB rarity is a function of where you are.  My
favorite pig pen here in Seattle has vats of oil two
stories tall labelled for varying degrees of PCB
contamination (and used to store reclaimed oil).  They
run into PCBs all the time, though *usually* not in
any great concentration.  Still, even some very
recently-built transformers may be contaminated with
small amounts of PCBs (below the EPA-mandated 50ppm
max) simply because they're made using equipment that
was used back in the day when PCB use was more common.
 That, at least, is the story I've been given.

Dry-type 10kV 5kVA transformers?  Get em!

Regards,
Aaron, N7OE

--- Tesla list <tesla@xxxxxxxxxx> wrote:

> Original poster: gary350@xxxxxxxxxxxxx
>
> I talked to Bobby Stevens at the power company
> maintenance shop.  He
> says it is extremely rare to find a transformer
> these days with
> PCBs.   The last one they found was 5 years ago.
> They dump the PCB
> oil into a burn tank with lots of other used oil and
> set it on fire.
>
> There are 3 old power line transformers at the scrap
> yard that the
> power company trashed.  They are all DRY type
> transformers.   The tag
> on one transformer is marked 110 VAC secondary,
> 10,000. VAC primary,
> single phase, 5 KW, the date is 1950.  The
> insulators on top are
> about 4" tall.   The tag on the other transformer
> says the same thing
> only difference is its 3KW.   The other transformer
> has NO tag but
> the physical size is identical to the 3KW
> transformers.   Bobby
> Stevens said they were cleaning up and found them
> back in the corner
> of the building probably been there for 50 years.
> He figures they
> are probably good other wise they would not have
> been saved all these
> years.   They can be bought at the scrap yard but I
> did not ask, HOW
> MUCH.  I figured they arn't much good being 110
> volts 45 amp.   What
> do you all thing???
>
> Gary
>
>
>
>
>
> -----Original Message-----
>  >From: Tesla list <tesla@xxxxxxxxxx>
>  >Sent: Jul 12, 2006 7:48 PM
>  >To: tesla@xxxxxxxxxx
>  >Subject: Re: PCB test kits
>  >
>  >Original poster: "David Rieben"
> <drieben@xxxxxxxxxxxxxxx>
>  >
>  >Dan, all,
>  >
>  >I would have to agree with you here. I'm sure a
>  >"basically" petroleum based fluid would burn quite
>  >nicely with a far greater concentration of PCB
> con-
>  >taminant than 50 PPM! 50 PPM PCB is the maximum
>  >EPA contamination level allowed and I'm sure
> 1/20,000th
>  >part PCB would not impede the combustible
> character-
>  >sitics of petroleum by any perceivable amount, nor
> would
>  >much higher concentrations of PCB, say 40X more
> PCB
>  >concentration, or 1/500th part. PCB itself is not
> combustible,
>  >but I don't think it's going to have a "halon"
> effect when mixed
>  >in small concentrations with petroleum based
> liquids, either.
>  >
>  >David Rieben
>  >
>  >----- Original Message ----- From: "Tesla list"
> <tesla@xxxxxxxxxx>
>  >To: <tesla@xxxxxxxxxx>
>  >Sent: Wednesday, July 12, 2006 6:37 PM
>  >Subject: RE: PCB test kits
>  >
>  >
>  >>Original poster:
> <dhmccauley@xxxxxxxxxxxxxxxxxxxxxxxxxx>
>  >>
>  >>The "burn test" is a very poor indicator of PCBs.
>  Mixtures that contain
>  >>non-PCB oil mixed with PCBs still tend to burn.
> I have had about 4
>  >>transformers i've tested that were negative on
> the burn-test, but positive
>  >>on the chemical test.
>  >>
>  >>Dan
>  >>
>  >>
>  >>
>  >> > The "burn test" is usually a good indicator.
> Dip a piece of paper
>  >> > into the oil and try to light it.
>  >> >
>  >> > Dr. Resonance
>  >> > ----- Original Message ----- From: "Tesla
> list" <tesla@xxxxxxxxxx>
>  >> > To: <tesla@xxxxxxxxxx>
>  >> > Sent: Wednesday, July 12, 2006 1:07 PM
>  >> > Subject: PCB test kits
>  >> >
>  >> >
>  >> > >Original poster: Gomez Addams
> <gomezaddams@xxxxxxxxx>
>  >> > >
>  >> > >A while back, someone posted a source for
> relatively
>  >> > >inexpensive PCB test kits.  I've got a Korean
> War era
>  >> > >x-ray transformer that I'm deciding what to
> do with,
>  >> > >and whether it contains PCBs will impact my
> decision.
>  >> > >
>  >> > >  - Bill "Gomez" Lemieux
>  >> > >
>  >> > >.
>  >> > >
>  >> > >
>  >> >
>  >>
>  >
>  >
>  >
>  >
>
>
>