Classifications and Applications of Insulating Coatings for Electric Power

Generally, the electrical conductivity of insulating coating for electrical power facilities is 10-22~10-12Ω-1cm-1. This kind of electrical insulating coating usually uses varnish. It is a coating composed of the polymer as the main film - former, solvent, and thinner. The insulation, heat resistance, and mechanical properties of the insulating layer for electrical power facilities are excellent. Those performance features determine the composition, structure, and molecular weight of the film-former.

Ⅰ. Electrical insulating coatings classified by facilities usages

1. The first type is called the Y class, which can withstand the highest operating temperature of 90 degrees.

2. The second type is A class which can work at 105 temperature.

3. The third type is E class which can regularly work at 120 degrees.

4. The fourth type is B class which can withstand 130 degrees.

5. The fifth type is the F class which can withstand a high temperature of 155 degrees.

6. The sixth type is H class which the maximum working temperature can reach 180 degrees.

7. The seventh type is the C class which can withstand the maximum working temperature above 180 degrees. This particular electrical insulation coating has additional properties, such as heat resistance, fluorine resistance refrigerants, good thermal high-frequency electrical insulation, and other properties. It can be applied for work with special requirements. The criteria for evaluating the properties of electrically insulating coatings is to check the electrical breakdown strength, dielectric loss, withstanding highest temperature, thermal softening breakdown, cold and hot impact, volume resistance, dielectric constant, thermal aging, and chemical resistance medium, and other aspects. This type of material property determines the miniaturization, service life, and reliability of high voltage and large capacity electrical equipment and electronic components.

Ⅱ. Electrical insulating coatings classified by the drying methods

Based on the drying methods, electrically insulating coatings can be classified into two types: drying paint and air-dried paint. Drying paint needs to be dried into films at a higher temperature. Most of them are used for insulating paints. Air-dried paint is a paint film that can be formed at average room temperature.