What is the correlation between the temperature rating of the insulating frame material (such as UL94V-0) and the operating temperature of the common mode inductor?

UL94V-0 is a flame retardant rating (indicating that the material is not easily combustible and self-extinguishes quickly), rather than a direct upper temperature limit. However, the long-term operating temperature resistance of the frame material (such as PA66 at approximately 100-120℃, PBT at approximately 120-150℃) needs to be higher than the actual operating temperature of the common mode inductor. If the temperature resistance rating of the frame is lower than the operating temperature of the inductor, it can lead to material softening, deformation, or even decomposition, damaging the winding insulation and core positioning, causing short circuit risks or drift in inductor parameters (such as inductance and impedance), and ultimately losing common mode suppression capability.