Designation of capacitors: domestic and foreign standards

The designation of capacitors in accordance with domestic standards and according to foreign standards places significantly different, and in some places - has much in common.
In any case, such information is of interest only to those who constantly service or repair electronic devices. The rest of our
Compatriots finished their education on this issue in the school course of physics.

What it is?

Before we look at the designation of capacitors, let's define what kind of device it is, what it represents. It is also known from the school course of physics that a capacitor accumulates an electric charge. It can be compared with a container for filling with water. The latter with such a comparison is a charge. Like the capacitor, the capacitor also has its own unit of measurement. The main one is Farad. But in practice, its derivatives with pico attachments (10 ^-12 ), nano (10 ^-9 ) and micro (10 ^-6 ), respectively, are used.

On the diagram

As in domestic and foreign drawings, the designation of capacitors is identical. These are two parallel lengths of 10 mm, which are between each other at a distance of 1.5-2 mm. Also, the alphanumeric designation "CX" should be on the right or above. "C" in this case is the element type, that is, the capacitor, and "X" is the serial number of this group of components in the diagram. Domestic State Standard 2.728-74 recommends that they be numbered from top to bottom, from left to right. But this practice is gradually disappearing into oblivion and marking is done in an arbitrary order. If the capacitor is electrolytic, next to one of the segments will be plus (positive contact of the element). The variable is crossed out by the arrow under
Angle of 45 degrees. The trim is indicated in a similar way, but instead of the arrow two segments are used in the form of our letter "T".

Domestic standards

Condensers manufactured by national standards are designated, for example, K72-83. In this case, K is a constant radio element (CT-tuning, KP-variable), 72-the type of material used (in our case
Fluoroplastic). The last component of the marking is the designation of capacitor capacitance. In our case, 83 is 0.083 μF. In this example, it is easy to understand the principle of marking. But this is only true if the part is large enough and you can put numbers and letters on its body.

But if it is very miniature, then you have to use overseas designations, which do not yet have a rigid structure and depend on the manufacturer.

International standards

The designation of imported capacitors on the housings is very complex for today
day. For these purposes, color marking is used, which for each manufacturer can differ significantly. Therefore, immediately it is necessary to study the reference literature and understand the notation. Those who constantly work with such equipment already know by heart their marking and can determine the parameters of the elements "on the fly."

As a result

Within the framework of this article, the designation of capacitors is shown both on the circuit and on the casing. If the labeling on the diagram is identical, then the shells differ significantly. This information is of particular interest to professionals who are constantly working in this industry.