Causes of Unstable Speed in Stainless Steel Centrifugal Fans

Causes of Unstable Speed in Stainless Steel Centrifugal Fans Troubleshooting for Stainless Steel Centrifugal Fans: These fans utilize variable-speed motors. Speed is adjusted via a variable resistor, while voltage across the rectifier motor terminals is controlled by a rectifier to achieve speed regulation. "The motor's rotational speed is unstable. Based on the operating principles of stainless steel centrifugal fans, the following four scenarios may be considered: (1) The adjustable resistor is mounted on the control panel. Frequent use and prolonged operation often lead to poor contact. (2) The trigger may suffer from short circuits, open circuits, failure to trigger, or internal contact issues. (3) Only one of the four rectifier diodes is faulty. (4) Carbon powder or carbon brush defects exist between the motor rotor and rectifier. Following the simplest first principle, the difficult-to-adjust resistor was measured first, confirming its resistance value changes as expected. The potentiometer functions properly. The potentiometer was re-measured with no issues found. After testing all four rectifier diodes, one was found to be in good condition. The rectifier diodes are high-current gold-sealed tubes. One end of each diode is secured to the substrate with screws. The other end is soldered to the circuit board with wires. During measurement, verify that the stainless steel centrifugal fan and switch are operational. "Since the tube type was unknown, an identical specification tube was installed. Power was restored quickly." The test tube had just failed, and the measurement results were deemed normal. "Typically, the other three diodes are measured, but comparing the readings reveals that two diodes have completely opposite polarities (meaning the screw end is the positive terminal and the other end is the negative terminal). Stainless steel centrifugal fan. "Therefore, during installation, it is crucial to use parts of the same model and specifications." "After replacing the parts with identical specifications and models, debugging commenced, and all functions returned to normal."