PCB board consists of contactor, relays, buttons and other components. When operating them, they produce spark discharge which is dangerous. So, a RC absorption circuit is needed to Absorb the discharge current.

How to select a right capacitor depends on the operating frequency and the impact of harmonic frequency on the PCB board. You can click www.csdcapacitor.com to check our capacitance data, making the options according to the needs. If your PCB main working frequency is low, it is ok to add two capacitors, one in addition to the ripple, one in addition to the high frequency signal.

Speaking of capacitors, all kinds of way can make people dizzy, such as x2 safety capacitor, film capacitor, power electronic capacitors, etc. But the principle of the capacitors is same, using the low impedance of ac signal. This can be displayed by the equivalent impedance formula: Xcap=1/2лfC. Higher the working frequency and capacitance, smaller the impedance.

Metallized film capacitors used the polyester film or polypropylene film as medium, and Zn-Al alloy was attached to the film surface by the empty evaporation method. All of this formed electrode, and after winding non-inductive or laminating, metalized film capacitors was formed. Metallized film capacitors have the capacity with high voltage, high insulation, low ESR, high capacitance stability and low loss tangent.

Each of the capacitors has two plates, separated by a layer of insulation. Therefore, in normal situation, there is no current could pass through the capacitors.

As the capacitor is connected to a DC circuit, there is a moment of charging. When the capacitance voltage is equal to the power voltage, no current is travelling. So, DC is isolated by capacitors.

When the capacitor is connected to an AC circuit, there is also a moment of charging. When the capacitance voltage is equal to the power voltage, stop charging. Then the power supply voltage drops, capacitor began to discharge. When the reverse voltage rises, capacitor starts to charge reversely. Then discharge reversely. Charge and discharge repeated alternation in the form of current. That is why current can pass by capacitors. Using this characteristic of the capacitors, in rectified circuit, the output circuit is smooth after rectified.

More details in www.csdcapacitor.com

  Phones : 86-755-29948886
 E-mail : sales@csdcapacitor.com