Insulation insulation class insulation materials according to the heat capacity is divided into Y, A, E, B, F, H and C7 levels, its limit working temperature is respectively 90, 105, 120, 130, 155, 180 ℃, and above 180 ℃. Performance reference temperature (℃)A80E95B100F120H145 insulation materials according to the thermal stability can be divided into the following seven levels: 1, and Y, 90 degrees, cotton 2, class A, 105 degrees, 3, E, 120 degrees, 4 B, 130 degrees, mica, 5 F, 155 degrees, 6 of epoxy resin, class H, 180 degrees, silicone rubber 7, class C, above 180 degrees the commonly used class B motor, its internal insulation material is often F, and copper wire may be using H level or higher, to improve its quality. in general in order to improve the service life, often advanced insulation requirements, low level for review. Common class F insulation of the motor, for example, do B to examination, namely the temperature cannot exceed 120 degrees Fahrenheit (Remain 10 degrees as a cushion to avoid process instability caused by individual motor temperature rise out-of-tolerance)。 the so-called limit working temperature of the insulating material, refers to the motor within the design life expectancy, runtime winding insulation in the hot temperature. According to experience, grade A material in 105 ℃, the class B material at 130 ℃ under the condition of life can be up to 10 years, but in the actual environment temperature and the temperature rise are not up to design value for A long time, so in 15 ~ 20 years of life in general. If the operating temperature more than material limit working temperature for a long time, the aging of the insulation, shorten service life. So the motor in operation, the temperature is one of the main factors of life.
