A non-polar capacitor is a capacitor without the positive and negative poles of the polar power supply. The two electrodes of the non-polar capacitor can be connected in the circuit at will. Because this capacitor has no leakage phenomenon, it is mainly used in coupling, decoupling, feedback, compensation, and oscillation circuits.
The two electrodes of the non-polar capacitor have no positive and negative polarity. They are mainly used in AC circuits, high-frequency pulsating DC circuits, and low-frequency pulsating DC circuits. In electric fans, washing machines, refrigerators, range hoods, dry cleaning machines, vacuum cleaners and other household appliances, the infinite capacitor is used as a starting capacitor for a single-phase AC motor.
The working principle of the non-polar capacitor in the single-phase AC motor circuit is very simple, that is, after the AC current passes through the capacitor, a large phase difference between the supply voltage and the current is generated, so that the voltage between the two windings of the single-phase motor The torque is generated due to the existence of the phase difference, which makes the motor start and run.
The capacitors used in single-phase AC motors in household appliances are generally oil-immersed large-capacity electrodeless capacitors, which are divided into oil-immersed paper capacitors, metalized paper capacitors and metal film polypropylene capacitors. The surface of this type of capacitor is marked with “AC” or “50H”. It means that it can be used in alternating current, and its voltage withstand voltage is generally AC400V~AC600V. Some capacitors are marked with the words fan capacitor, washing machine capacitor, etc., which proves that they are special capacitors for this appliance.