Gas vapor and fire resistant transformers

A project was conducted to develop a new fire and explosion resistant transformer as an economic replacement for PCB units. Two types of designs were considered. One was a liquid poor design insulated with a completely fluorinated liquid, and a second, more economical design, utilized a completely immersed core and coil design. A review of the liquids and major solid insulating materials that were used in three prototype transformers is included. A fire resistant transformer was developed at a cost level close to oil filled transformers.