The main power source of the centrifugal fan is the motor. The rotation of the motor drives the transmission components such as couplings and belts to rotate the impeller, and then starts to induce or supply air. However, in some cases, the motor overcurrent will occur after the centrifugal fan is started. In severe cases, the motor will be damaged. What is the reason for the overcurrent of the centrifugal fan?
Causes of overcurrent in centrifugal fans
1. Phase loss of power supply: If the centrifugal fan adopts three motors, if there is no comprehensive protector installed, the motor will still run in the state of missing items, but the three currents are seriously unbalanced. Overheating occurs.
2. Motor bearing damage: Slight bearing damage, the motor of the centrifugal fan can still continue to run, but with the increase of friction, the motor running load increases, which will lead to overcurrent.
3. Fan overload: The motor has its rated power. If the model is not properly selected, or the fan suddenly increases the load, once the motor is beyond the bearing range, it will overheat and overcurrent, and even burn in severe cases. bad motor.
4. Poor heat dissipation: Although the centrifugal fan is a ventilation device, its motor position is generally not within the operating range of the centrifugal fan, so separate ventilation and heat dissipation conditions are required, and poor heat dissipation will cause the motor temperature rising, which in turn leads to superfluidity.
5. The starting load of the fan is too large: When the centrifugal fan starts, it is generally required to close the intake valve, which can greatly reduce the starting load. It is prone to overload phenomenon, resulting in overcurrent.
6. The fan speed is too high: The efficiency of the centrifugal fan can be improved by adjusting the speed of the impeller, but it does not mean that the speed can be increased at will, but it needs to be based on the bearing capacity of the motor. If the motor speed is increased, the motor speed will also increase accordingly. Once the rated value is exceeded, it will overcurrent.
7. Coupling connection failure: The coupling of the centrifugal fan is the main component to ensure the motor transmission. When the rubber ring is too tight, the motor load will increase. In addition, if the coupling clearance is not Evenly, it will cause the load to vary as the spindle rotates, causing overcurrent.
The reasons for the overcurrent of the centrifugal fan are basically the above. It is not difficult to see that the main reason is that the maintenance work is not done properly, and there are also shortcomings in the operation and selection, so the main solutions are still in the following aspects, you can According to the specific situation to choose a treatment method.
The method of solving centrifugal fan motor overcurrent
1. Install thermal relay: In the face of the lack of power supply, you can install a thermal relay, that is, a comprehensive protector. When the current of the centrifugal fan motor reaches a certain value, the thermal relay will start to protect work to prevent the motor from burning out.
2. Regular maintenance: Regular maintenance of the various parts of the centrifugal fan and motor. Once the bearing is found to be worn, it should be replaced in time. After each maintenance, pay attention to the correct connection of the coupling, and check at the same time The balance of the rotor.
3. Correct motor selection: When selecting centrifugal fans, the motor type should also be correctly selected, and the load conditions of the fans and motors in the future should be fully considered. When necessary, a variable frequency motor should be selected, or an inverter should be added .
4. Ensure the operating environment of the fan: Before installing the centrifugal fan, the operating environment of the fan and motor should be designed to avoid overcooling or overheating. If it is indoors, ventilation and heat dissipation should be done well.
5. Operate the fan correctly: To operate the fan equipment correctly, make preparations before the centrifugal fan starts, adjust the fan in advance, and adjust the fan speed in time during operation.
