1. Look at random files
The motor fan comes with instruction manual, product qualification certificate, electrical circuit diagram and packing list. Check the packing list and check the parts.
2. Look at the appearance of the motor fan
Check carefully whether the motor fan net cover and fan blades are obviously deformed. Rotating the fan blades should be brisk and flexible, and should not always stop at the same position.
3. Look at the startup performance
The starting performance is an important quality index of the motor fan. During the inspection, in the slow gear, when the rated voltage of the power supply is 85%, the motor fan should be able to start from a standstill and operate normally. The shorter the time required for a motor fan to start to normal operation, the better the starting performance of the motor fan.
4. Look at the speed regulation performance
After power-on, there should be no abnormal noise in the mechanical drive part of the fan. When the electric fan is running at high, medium, and low speeds, the motor and fan blades should be stable, with low vibration and low noise. The motor fan should be agile when shaking its head and stopping, without intermittent, stagnation and jitter.
5. See if there is electricity leakage
After the motor fan is powered on, if there is a feeling of numbness when touched by your hand, use a test pen to test. The test pen also has a luminous display, which can determine that the shell is leaking.
6. Look at the continuous operation of the motor fan
After the electric fan is running continuously, if the surface of the machine head shell is hot, it means that the temperature is too high and it cannot be used. Under normal circumstances, the surface temperature of the machine head shell is below 50℃, and there should be no hot feeling.