"Micro Cooling Fan" operating conditions is accompanied by heat and changed to slow speed operation, will produce less DC fan noise and consumes less energy. DC fan slow temperature changes, the fan speed changes relatively slowly, not suddenly change "Micro Cooling Fan" speed and noise. The reaction time depends mainly on the length of its heat-sensing sensor sensitivity. In most of the design requirements, the operating speed DC fan for several hours after the air temperature is usually lower than the maximum design temperature value. Under normal circumstances, low-speed operation of the "Micro Cooling Fan" can be enough to complete its work. However, in the selection and installation should also be considered.