How good Waterproof Cooling Fan?

Often there are many people in the replacement, buy "Waterproof Cooling Fan" when buy direct power, large fan blades that the wind was such a fan is large enough, there is a very good cooling effect. These perceptions are very wrong. Wind source below to tell you, when you buy cooling fan is required to have some knowledge of the purchase.
1, "Waterproof Cooling Fan" is not a fan bigger the better, big fan blades during operation of the process, the resistance is great, when the choice of blades can be moderate;
2, is not a big fan of power, cooling the fruit, the better, the General Assembly had the power to affect the normal use of machinery and equipment, in the choice should be selected according to actual usage;
3, to choose a good quality "Waterproof Cooling Fan", after the purchase to the fan speed accordingly to debug.