Re: Does my transformer have PCB oil????????

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

Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bert.hickman-at-aquila-dot-net>

Hi Dan,

PCB's were first synthesized in 1881. Initial production of PCB's began
in 1929 by Swann Chemical, which was later purchased by Monsanto. GE
patented the use of PCB's as a fire resistant dielectric fluid, and
Monsanto became the world's largest supplier of PCB's for electrical
use. PCB's were also used as plasticizers in paints, sealants, caulking,
etc. Virtually all buildings built between the 1950's and 1970's have
PCB's in the building material. 

The odds are actually with you - most PCB's were actually used in
capacitors. Only about 5% of all transformers made before 1978 used it,
primarily at locations that demanded fire resistant dielectric fluid,
such as inside buildings. The US Environmental Protection Agency (EPA)
banned the manufacture of PCB's and regulated their use in 1978. If a
transformer oil contains PCB's, it's most likely a blend of chlorinated
benzenes and chlorinated diphenyls, and it will have a marked sweetish,
solvent-like aromatic odor, a marked yellowish tint, and low, water like
viscosity. Also, the density of PCB's is considerably higher than water
(~1.5X). 

Try the specific gravity test or burn test. If it smells like motor oil
and a sample floats on water, then it's mineral oil. Mineral oil starts
out a light straw color, but it often darkens with age and heat. If a
sample of your transformer's oil sinks in water and refuses to burn,
it's a pretty good indication that you're transformer uses PCB's. 

Good luck and best regards,

-- Bert --
-- 
Bert Hickman
Stoneridge Engineering
"Electromagically" (TM) Shrunken Coins!
http://www.teslamania-dot-com

Tesla list wrote:
> 
> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<dhmccauley-at-spacecatlighting-dot-com>
> 
> I just acquired another old GE transformer, and was wondering if anyone
> would know if there was PCB oil in it.
> 
> GE Pole Transformer
> Black Cast Iron type approximately 50-60 years old.
> 4000V Primary - 120/240 center-tap secondary
> 
> I think the transformer was probably made way before PCB oil was being used,
> but just wanted to make sure.
> 
> Dan