A centrifugal fan is a complex device, mainly composed of an inlet, damper, impeller, motor, and outlet. The performance of a centrifugal fan varies under different conditions. Therefore, inconsistent operation of different parts will affect the fan's performance. To optimize the centrifugal fan's performance, several aspects can be addressed.
1. Centrifugal fans can be started at full voltage or with reduced voltage. However, it should be noted that the starting current at full voltage is approximately 5-7 times the rated current. Reduced voltage starting torque is proportional to the square of the voltage. When the mains power supply capacity is insufficient, reduced voltage starting should be used.
2. During commissioning, carefully read the product manual and check if the wiring method matches the wiring diagram. Carefully check if the operating voltage of the power supply to the fan meets the requirements, whether there is a missing phase or phase mismatch, and whether the capacity of the electrical components is sufficient.
3. At least two people should be present during trial operation: one to control the power supply and the other to observe the fan's operation. If any abnormalities are found, immediately stop the machine and inspect it. First, check if the rotation direction is correct. After the centrifugal fan starts running, immediately check if the operating current of each phase is balanced and if the current exceeds the rated current. If any abnormalities are found, stop the machine and inspect it. After running for five minutes, stop the machine and check for any abnormalities. Only restart the machine after confirming there are no abnormalities.
4. When testing a dual-speed centrifugal fan, start at low speed and check if the rotation direction is correct. When starting at high speed, wait until the fan has come to a complete stop to prevent reverse rotation at high speed, which could cause the circuit breaker to trip and damage the motor.
5. When the centrifugal fan reaches its normal operating speed, measure the fan's input current to ensure it is normal. The operating current of the centrifugal fan must not exceed its rated current. If the operating current exceeds its rated current, check if the supplied voltage is normal.
6. The required motor power for a centrifugal fan refers to the maximum power required for the centrifugal fan and fan housing with the inlet fully open under certain operating conditions. If the air inlet is fully open during operation, the motor may be damaged. When testing the fan, it is best to close the valves on the fan inlet or outlet pipes. After starting operation, gradually open the valves until the required operating conditions are reached, and pay attention to whether the fan's operating current exceeds the rated current.
