Insulation materials are commonly used products by electricians. There are many types of insulating materials, such as electrical insulating paint, Insulation sheets，electrical composite insulating paper, insulating board, insulating film (polyester film/polyimide film, etc.).

The function of insulating materials is to isolate live parts of different potentials in electrical equipment. The insulating material has high insulation resistance and compressive strength, and can avoid accidents such as leakage and breakdown. Secondly, the heat resistance should be good, to avoid long-term overheating and aging and deterioration; in addition, it should also have the characteristics of good thermal conductivity, moisture resistance and lightning protection, high mechanical strength and convenient processing.

Classification of heat-resistant grades of insulating materials:

According to the degree of heat resistance, the insulating materials are divided into 7 grades: Y, A, E, B, F, H, C, etc.:

Y-class insulation temperature resistance 90 ℃ A-class insulation temperature 105 ℃

Class E insulation temperature resistance 120°C Class B insulation temperature resistance 130°C

Class F insulation temperature resistance 155℃ H class insulation temperature resistance 180℃

Class C insulation temperature resistance above 200 ℃.