Insulating materials are particularly susceptible to accelerated aging and damage due to high temperatures. Different insulating materials have different heat resistance properties, and electrical equipment using different insulating materials have different ability to withstand high temperatures. Therefore, general electrical equipment stipulates the maximum ambient temperature for its work.

The insulation class of fans is usually divided according to the withstand voltage capability of their insulating materials. The common fan insulation grades are as follows: A, E, B, F, H. The allowable temperature rise refers to the limit of the temperature rise of the motor compared with the ambient temperature.

Grade A: temperature resistance 105°C, suitable for low temperature industrial occasions.

Grade E: temperature resistance 120 °C, suitable for industrial occasions with lower temperature.

Grade B: temperature resistance 130°C, suitable for industrial occasions with lower temperature.

Grade F: temperature resistance 155°C, suitable for general industrial occasions.

Grade H: temperature resistance 180 °C, suitable for industrial occasions under high temperature environment.

The insulation grade of our ebmpapst fan is generally "B" or "F", and the insulation grade of small fans is basically E.

The insulation grade identifies the withstand voltage capability of the fan insulation material, and different grades are suitable for different working environments and temperature conditions. When selecting a fan, it is necessary to determine the required insulation level according to the specific use requirements and environmental conditions.