Dust Removal Centrifugal Fan it can be used for indoor ventilation in general factories and large buildings to transport air and other unnatural gases that are harmless to the human body and non-corrosive to steel.
The centrifugal fan for dust removal is a DC speed-adjustable motor. The speed of its speed is to change the conduction angle of the thyristor through an adjustable resistance, and then the thyristor controls the rectified voltage reaching both ends of the motor to achieve the purpose of controlling the speed. "The motor speed is unstable. From the principle analysis, the following four situations are possible:
1. Adjustable resistance, because the adjustable resistance is installed on the control panel, the frequency of use is very high, and it is very common to have poor contact after a long time;
2. There are also many problems with the thyristor, usually a breakdown short circuit, an open circuit, a failure to trigger or poor internal contact, etc.;
3. One of the four rectifier diodes has only a problem;
4. There is carbon powder between the rotor and the commutator of the motor or the carbon brush itself is not good, etc. "Based on the repair principle of easy first and then difficult, first measure the adjustable resistance, the resistance value changes regularly with adjustment, which proves that the potentiometer is good The "re-measurement of the thyristor did not find any problems". When measuring the four rectifier diodes, it was found that one of them was good and sometimes bad, because the diode is a high-current gold sealed tube. "One end is screwed on the circuit board, and the other end is Solder it to the circuit board with a wire. When it is removed from the circuit board, it is found that the positive and negative poles are loose, and then shake while measuring to confirm that the diode is good or bad. Since the model of the tube cannot be seen clearly, put the same specification The tube is installed, and the speed is very fast when the power is turned on. It is believed that the new tube is broken down, and the measurement is intact. "The other three diodes are also normal." On the contrary (that is, one end of the upper screw has a positive polarity and a negative polarity)" so when installing the dust removal centrifugal fan, it must be noted that it is best to use the same type and the same specification of components" When replacing the same specification and the same type of components , Power on and test the machine, everything is back to normal.
