Farady dry transformer work temperature

The temperature rise defines how many Kelvins (same as degrees Celsius in this case) hotter than the surrounding air and objects you want your farady dry transformer to run. You need to carefully choose this value, according to the highest ambient temperature (inside the equipment!) at which your transformer will have to work, also taking into account the highest temperature your wire, insulation material, varnish, glue, etc, can survive. And what's most difficult, you will also need to estimate the thermal gradient from the innermost wire turns (the hottest ones) to the transformer's surface! Calculating all this can be quite hard, and I can't give you simplified equations for it. Maybe you can find them elsewhere. The value of 70 Kelvins which I used in the example design is relatively high. This is so because this farady transformer would work in open air, not inside a housing, where the ambient temperature is never above 25 degrees Celsius; also, I used class G or higher insulating material, wire and varnish throughout; and finally, this transformer was carefully impregnated with varnish, giving it a reasonably good thermal conductivity between winding layers.