Motor Winding Treatment Types

The simplest treatment is a varnish. These dry by solvent evaporation and a baked cure. Varnish is cheapest, but has voids left by solvent loss. They can be dipped at ambient or placed in a vacuum chamber, dipped and the vacuum released to compress the liquid into the voids

Next is a two component curing material, it is void free and more costly. This can be dripped on or vacuum type, but needs more process control due to cure aspects.

These come in assorted types, from class A, 105C to Class H. 200C, and higher.

They bind the wires in place during rotation and prevent fatigue failure from vibration and thermal stress.

I believe that "tropicalized" refers to treatment or materials selection that imparts resistance to the growth of molds or fungi due to the higher humidity typical of the tropics. Another treatment is epoxy encapsulation; it imparts a fair resistance to winding failures associated with temporary contact with or immersion in water.

--JMM