"220V Cooling Fan" automatic thermostat radiator general category with a thermostat sensor, according to the current working automatic temperature control fan speed, the speed is increased by high temperature, low temperature, then reduce speed to achieve a dynamic balance , so that the cooling effect of wind noise and to maintain an optimal combination of points. "220V Cooling Fan" With the application and environmental temperature changes, sometimes it requires a different fan speed to meet demand. Some vendors specially designed adjustable fan speed cooling fan, manual and automatic modes. Manual is designed to allow users to use low speed in the winter to obtain a low noise, high speed get good cooling effect in the summer. Speed and "220V Cooling Fan" quality is not necessarily linked. Fan speed can be measured by the internal speed signal, it can also be measured by the external.