On Mon, 3 Jan 2005 10:37:23 -0800, "Jon Danniken"
wrote:


How many transformers do you have in your house, Doug?
How many of those contain PCBs?
What types of transformers used PCBs, and what was the purpose for the PCBs?

Jon

Jon --

Let me try to answer your last question. I'm no transformer expert,
but I worked in power plants my entire career. I know just enough to
be dangerous.

Generally speaking, large power transformers used PCBs. The liquid in
the transformer acted as a coolant that carried away heat to heat
exhangers of one kind or another. Most of them rejected their heat to
water or atmospheric air.

One of the ways to classify transformers is by their method of
cooling. O/A were oil/air cooled. O/W were oil/water cooled
O/A/F were oil/air/fan, etc. (I might be incorrect on that last one.
It might be O/FA.)

The PCBs were valued for their fire-suppressant properties. Thus, if
a transformer ever blew up there wasn't so much danger of fire.

Long before the days of environmental consciousness, folks who could
get their hands on transformer oil (PCBs) would slather it onto the
wood shingles on their houses. Not only would it help preserve the
wood, it would act as a fire supressant.

Regards,

Orrin