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Seek info: mid-20th century Power Factor Capcitors, Sangamo-Weston, Pickens, SC

pcb_researcher

Sep 29, 2011
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I am an Ecologist who did some work on PCBs at the Sangamo-Weston Superfund Site in Pickens, SC. I have an historical interest in the products made there and who used them. The plant used PCBs in capacitor manufacturing from 1955-1977, I believe. PCBs were used in "Power Factor Capcitors".

Is there anyone familiar with these products, the company, or the plant?
What were these capacitors used for?
Might anyone actually have one?
Is there anyone or any other websites to which you could refer me?

Thank you very much.
 

Resqueline

Jul 31, 2009
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Sangamo-Weston is an old internationally well-known brand.
I'd believe those capacitors were predominantly used in fluorescent lighting fixtures.
They would be connected directly across the mains supply and had a power-factor correction function. Their presence made the fixtures consume less current.
 

shrtrnd

Jan 15, 2010
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I don't know if you're going after capacitor manufacturers specifically, or what you're looking for.
The caps were the oil-filled cans used in just about every pre-transistor power supply
I worked on (by a lot of manufacturers).
If you want to know where all the PCB's are now, start looking into the large transformer
manufacturers. And filter capacitors in 480VAC motor control cabinets.
Nobody MANUFACTURES them anymore. But the transformers on the telephone
poles in a lot of neighborhoods are still full of them. They only get replaced when
they fail. (All installed in the 1970's and before)
 

pcb_researcher

Sep 29, 2011
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I'm interested in the historical context that lead to the creation of a plant that used Polychlorinated Biphenyls in its manufacturing process. That is, who invented capacitors and why? Who invented PCBs and how did they come to be used in this application? What was the demand that the products from this factory were meeting?

So far I gather that the demand for florescent light fixtures took off after WWII, hence the need for capacitors, an essential component, but anything more specific is better.
 

Resqueline

Jul 31, 2009
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Fluorescent lights are around 5 times more efficient at producing light than incandescent lights, thus beneficial for the electric bill.
Fluorescent lights used inductive ballasts to deliver the required lamp current without too much power loss. This had the drawback of a high current compared to power.
The PFC capacitors were not essential, but beneficial in that they reduced the current consumption (power consumption remaining constant), saving on wiring.
The only capacitors at the time capable of being connected directly across the mains were paper-oil types, but their reliability were still not good enough.
PCB's were then found to enhance the properties of the oil, making it more able to withstand the electrical rigors without breaking down so easily.
Big oil-cooled transformers were also using this additive for the same reasons; to stabilise the oil.
I don't know who invented PCB's or who found them to be useful as an electrical oil additive.
 
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