Advantages of film capacitors and power-on conditions

1. Advantages of film capacitors

(1) Film capacitors The temperature range to which it is applied is relatively wide and is limited by temperature;

(2) Its service life is very long, as long as there is no damage, there will be almost no limit on the service life, and it can be used for a long time;

(3) Film capacitor It is a metalized electrode, which has a self-healing function and can be automatically repaired when there is small damage;

(4) This device can withstand high voltages during operation without problems;

(5) It has no polarity, and the ESR is also very low;

(6) When used, its frequency of use is relatively good.

2. Film capacitor energization

Film capacitors are manufactured and polarized similarly to the method of manufacturing aluminum electrolytic capacitors, however their storage time is not limited and can be operated for a long time without DC polarity. The instantaneous counter voltage generally does not damage the capacitor, and the aluminum electrolytic capacitor is different.

In practice, there is not always a DC bias voltage. Non-polar tantalum capacitors can also be manufactured, but they are more expensive and not necessarily used after storage. If two identical tantalum capacitors are connected in series back to back, a non-polar capacitor can be obtained. The total capacitance is half of each series capacitor, which is C/2.

A good performance film capacitor at the moment of power-on, the multimeter's hands should have a large swing; the larger the film capacitor capacity, the greater the swing of the hands, after the swing, the hands can gradually return to zero. If the capacitor does not swing when the power is turned on, the pointer of the multimeter does not swing, indicating that the capacitor is broken or open; if the pin always indicates the power supply voltage without swinging, it indicates that the capacitor has been short-circuited; if the hand swings normally, but does not return to zero , indicating that the capacitor has leakage current.