In aggressive environments where electric motors are regularly exposed to high temperatures alongside wet and corrosive substances, the insulation materials they are constructed from can quickly degrade over time.
Therefore, in order to keep these critical components operational, contamination and moisture ingress should be prevented where possible. Both contamination and moisture can create tracking paths through the winding, allowing electrical leakage to earth and, eventually, a motor to trip. For a motor to stand the test of time then, the insulation resistance must be maintained.
Thankfully though, there are some simple solutions whereby motors can be treated to resist moisture. These include dipping the winding in a polyester or epoxy resin to create a moisture-resistant coating, or a process called Vacuum Pressure Impregnation (VPI). Our experience suggests the latter is the most effective.
Read the full article in the September issue of DPA