"Tiny Cooling Fan" power, using test pencil checking metal parts, there should be no leakage phenomenon. He shook his head and shook his head when devices require coherent smooth, low noise, no gap pause, there should be no stagnation or sudden bounces or "giggle" sound phenomenon, shaking his head angle should be greater than 80 to 90 degrees. Requirements "Tiny Cooling Fann" in low gear can be activated when no "buzzing" sound, no vibration when the sound of "imperfections" sound, fast file running, howling, knock. In the swing position to start with the most low-end, the fan quickly up to speed, especially when under 0.85 times the rated voltage can be normal start; when changing gear, there are significant changes in the amount of wind; let "Tiny Cooling Fan" in rapid Dangxia operation, and shook his head means work, should be no significant unusual noise. Work within 30 minutes, without a clear sense of the motor hot (the lower the temperature the better the quality of the motor).