Abstract: Electrical inductive apparatus having a tank, an insulating and cooling liquid in the tank and an electrical winding structure immersed in the liquid, the liquid having a low vapor pressure and containing contaminants derived from various sources within the tank. Filter means associated with the liquid including a liquid recirculating device for degassing, demoisturizing, and filtering insoluble particles out of the liquid, whereby the liquid is decontaminated and upgraded in a continual process.

Abstract: Disclosed is a method of inhibiting the attack by perchloroethylene on copper and organic polymers subject to said attack, such as parylene, by adding to perchloroethylene about 20 to about 1000 ppm of a stabilizer having the general formula ##STR1## The preferred concentration of the stabilizer is about 40 to about 500 ppm. Also disclosed is an electrical apparatus containing copper or organic polymer subject to attack by perchloroethylene and perchloroethylene containing the stabilizer.

Abstract: Method and apparatus is disclosed for extracting and analyzing gas from a body of liquid such as oil in an electrical transformer. The oil is continuously moved by thermosiphonic action through a conduit in which a gas permeation cell is mounted. Oil within the conduit is air cooled to create a temperature gradient relative to the body of liquid for establishing the thermosiphonic movement. The permeation cell comprises a semi-permeable membrane supported about an elongate porous tube mounted concentric within the conduit so that gas contained within the liquid permeates through the membrane and into a chamber within the cell. An inert carrier gas is injected into and out of the chamber for carrying the permeating gas to a gas detector-analyzer unit.