Reasons for uneven speed of centrifugal fan

Centrifugal fans are ventilation and dust removal equipment in many companies. When centrifugal fans are used, sometimes the speed of centrifugal fans is uneven. So what is the cause?

1. One of the four rectified diodes has a problem.

2. The carbon powder or carbon brush of the motor rotor and commutator are not flat. Let's take a look at the adjustable resistance of the fan first. If its resistance changes with the adjustment, then this potentiometer is good. Since the current of this diode is relatively large, we can fix the screw at one end to the circuit. On the top of the board, there is one end soldered to the circuit board for him with a wire, so that he can be removed. If there is any looseness, it can be seen whether the diode is good or bad.

3. There are also many problems in the SCR, such as open circuit, poor contact, short circuit, inaccessibility and so on.

4. Since the adjustable resistor is installed on the control panel, the frequency of its use is very high. If it takes a long time, the problem of poor contact will appear.

The centrifugal fan is a DC speed-regulating motor, and its speed is changed by an adjustable resistance, and then controllable rectification is made at both ends of the motor, which can realize the control speed.