First, the choice of "220V Cooling Fan" must be able to provide sufficient amount of exhaust (speed), under the high temperatures of the hot air inside the cooling device; when the temperature is relatively low and less hot air when it is to do the opposite work. Next, the position sensor installed in the selection should be noted that the sensor in the proper position, as far as possible "220V Cooling Fan" sensor directly clamped requiring cooling surfaces. In the cooling fan operation, a temperature-controlled cooling fan will run at a faster pace if the thermistor temperature feel higher; while at lower temperatures, it will operate at a lower speed; and at these higher intermediate lower, "220V Cooling Fan" speed will hardly change due to temperature. Therefore, the speed of the cooling fan speed control is mainly based on the temperature difference between the heat sink induction passed automatically adjust.