06-04-2022, 12:57 AM
I dont know when PCBs arrived, probably in the 1950s along with many other nasties. Presumably transformers were oil cooled before PCBs. And presumably when used the PCB concentartion was more like 100%.
There's a fairly comprehensive article (particularly the "History" paragraph) on Polychlorinated biphenyl in Wikipedia, Bob. I gather transformers were oil cooled pre-1930 using 'ordinary' mineral oil but PCB was the ideal material for the job, being amongst other things, non-flammable. Apart from the unfortunate eco-toxic aspects of course.
There's a fairly comprehensive article (particularly the "History" paragraph) on Polychlorinated biphenyl in Wikipedia, Bob. I gather transformers were oil cooled pre-1930 using 'ordinary' mineral oil but PCB was the ideal material for the job, being amongst other things, non-flammable. Apart from the unfortunate eco-toxic aspects of course.