Insulation grade of epoxy glass fiber board

The grade of epoxy glass fiberboard mentioned by general customers is not a technical grade, but a grade of high temperature resistance of insulating materials. The insulating properties of insulating materials are closely related to temperature. The higher the temperature, the worse the insulation performance of the insulating material. In order to ensure the insulation strength, each insulation material has an appropriate maximum allowable operating temperature. Below this temperature, it can be used safely for a long time, and it will age quickly if it exceeds this temperature. According to the degree of heat resistance, the insulating materials are divided into Y, A, E, B, F, H, C and other levels. For example, the maximum allowable working temperature of Class A insulating materials is 105°C, and most of the insulating materials in distribution transformers and motors generally used are Class A, such as epoxy resin insulation boards and so on.

Insulation temperature class A class E class B class F class H class

The maximum allowable temperature (℃) 105 120 130 155 180

The winding temperature rise limit (K) 60 75 80 100 125

Performance reference temperature (℃) 80 95 100 120 145