"220V Cooling Fan" impedance will have two functions, one is the impedance protection, thermal protection, respectively, one is described as follows:
    1. Impedance protection to prevent motor burnout occurs when you shut down, the way to set the impedance of the motor winding (AC resistance), so that appreciation is maintained at a temperature below the burning temperature of the motor.
    2. The thermal protection to prevent burning "220V Cooling Fan" occurring when closing, the motor temperature reaches appreciation burnout temperature before cutting off the way through the heating element
Conventional "220V Cooling Fan" is not overheating protection, the normal DC cooling fan can only lock machine 2H, the temperature slowly rising, a long time, the motor will burn, IC will burn, which is a thermal protection an important role.