Moisture-proof cooling fan cooling fan [] proof of noise cooling fan http://www.szdosense.com/products-detail.asp?cpid=102 addition to the cooling effect of the fan working noise is also widespread concern. Fan noise is the size of the generated noise of the fan work, influenced by many factors, in decibels (dB). When measuring the noise of the cooling fan needs sunon less than 17dB noise silencer chamber is performed, one meter away from the cooling fan sunon, and aligned along the axis of rotation of the fan the fan air intake port, the use of A-weighted manner measurement. Sunon noise spectral characteristics of the cooling fan is also very important, so we must also use a spectrum analyzer records the fan noise frequency distribution, the general requirements of the fan noise to be as small as possible, but can not exist different tone. Fan sunon and friction, air flow related. Fan speed, the greater the amount of wind noise caused will be greater, in addition to the fan's own shock factor can not be ignored. Of course, fans of high-quality shock itself will be very small, but the first two were but it is difficult to overcome. To solve this problem, we can try to use larger size fan. Should be at the same air volume, a large operating noise at a lower fan rotational speed must be less than the operating noise of small fan at high speed. Another factor is that we tend to ignore the fan bearings. Due to the friction between the shaft and bearing fan rotates at high speed collision, it is also a major source of sunon cooling fan noise. SHENZHEN woo Electronics Co., Ltd. for your friendship Recommended: dosensehttp: //www.szdosense.com humidifier cooling fan http://www.szdosense.com/products-detail.asp?cpid=87