Sequential connection of capacitors as an option of capacity selection

Condenser - a very common radio components, which is found in all the circuit diagrams. It is two conductors separated by a dielectric (depending on the type of capacitors, various types of capacitors are used), that is, physically it is a break in the circuit, but a dielectric can accumulate a charge. The main characteristic of any capacitor is the ability to accumulate charge - capacity, and the nominal voltage of this charge. Electrolytic capacitors have a polarity and are characterized by a large capacitance and a wide range of voltages, paper can withstand high voltage, but have a small capacity. There are also devices with varying capacity, but each type has its own application.

Often radio amateurs are faced with the problem of selecting capacitors by capacitance or voltage. Professionals know: in the absence of the right one, it is possible to assemble a combination of several devices, a battery of them. In batteries, a combined, parallel and series connection of capacitors is permitted.

By connecting devices in parallel, you can achieve an increase in capacity. The total in such a battery will be equal to the sum of all the capacitances (Сэкв. = С1 + С2 + ...), the voltage on each element will be equal. This means that the minimum voltage of the capacitor applied in the connection is the maximum permissible for the entire battery.

A series connection of capacitors is used in cases where it is necessary to increase the voltage capable of withstanding devices or reducing their capacitance. In this variant, the elements are connected according to the following scheme: the beginning of one with the end of the other, that is, the "plus" of one with the minus of the other. The capacitance of an equivalent capacitor in this case is calculated by the following formula: 1 / Секв. = 1 / С1 + 1 / С2 + ... It follows from this that for two capacitors Сэкв = С1 * С2 / (С1 + С2), which means that the battery capacity will be Less than the minimum capacity used in it.

A capacitor bank often provides a combined (mixed)
compound. To calculate the capacitance of such a device, in which a parallel and series connection of capacitors is applied, the circuit is divided into sections, then each of them is calculated in turn. Thus, the capacitance C12 = C1 + C2 is calculated, and then Сэкв = С12 * С3 / (С12 + С3).

Thanks to the development of capacitor banks with different configurations and circuitry
Connection, you can pick up any capacity for any voltage of interest. Serial connection of capacitors, as well as combined, is used in many ready-made radio amateur circuits. In this case, it is necessary to take into account that each capacitor has a very important individual parameter - leakage current, it can unbalance the voltage at parallel connection and capacitance in series. It is very important to select the necessary shunt resistance.

When working with capacitors and electronics, do not forget about the rules of personal safety and the threat of electric shock.