I had no questions about metal-film capacitors. Most of them have a voltage of 63 V, and some - and more. And I until recently worked with devices whose voltages were below this value.
630V, 0.47 uF, 10%
But now, it's time to develop impulse power supplies, and it started! Condensers (torn from the corpses of old TVs) a lot, but to what they strain - hell knows! The risk of burning not only the capacitor itself, but the whole circuit, turned out to be very large. I had to dig the Great Pothole - the Internet.
It's a shame to admit, but I still could not find on the Internet a ready-made table of voltage codes for capacitors. I had to compile it myself on scant information.
630 V, 22 nF, 10%
100 V, 0.1 μF, 5%
In general, I bring to the public court a table of voltage codes for capacitors.
Yuzayte to health, and if there is something to supplement - send the codes!
| Letter | 0x | 1x | 2x | 3x |
| A | 10 | 100 | 1000 | |
| B | 12,5 | 125 | ||
| C | 16 | 160 | ||
| D | 2 | 20 | 200 | |
| E | 2,5 | 25 | 250 | |
| F | 315 | |||
| G | 4 | 400 | ||
| H | 50 | 500 | ||
| I | ||||
| J | 6,3 | 63 | 630 | |
| K | 8 | 80 | ||
| L | 5,5 | |||
| M | ||||
| N | ||||
| O | ||||
| P | 220 | |||
| Q | 110 | |||
| R | ||||
| S | ||||
| T | (50) | |||
| U | ||||
| V | 35 | 350 | ||
| W | 450 | |||
| X | ||||
| Y | ||||
| Z | 180 |
Typically, the capacitors are applied to the value of the capacitance, tolerance and nominal voltage.
Voltage can be indicated as explicitly, for example, 100V, 250V, 630V and in the form of a code. Moreover, it should be noted that there are two systems of voltage coding in the world.
The first system has a one-letter value. Normally, the voltage is encoded on metal-film capacitors. (Maybe ceramic, but I'm not sure.)
Here is the table:
| For example, B | Letters. Ref. | For example. AT | Letters. Ref. | For example. AT | Letters. Ref. | For example. AT | Letters. indicium | For example. AT | Letters. indicium |
|---|---|---|---|---|---|---|---|---|---|
| 1,0 | I | 6.3 | B | 40 | S | 100 | N | 350 | T |
| 2,5 | M | 10 | D | 50 | J | 125 | P | 400 | Y |
| 3.2 | A | 16 | E | 63 | K | 160 | Q | 450 | U |
| 4.0 | C | 20 | F | 80 | L | 315 | X | 500 | V |
I took this table somewhere in the publicly available sources. Where exactly - I do not remember! Find on the Internet this table is not difficult. It is published in many places.
Unfortunately, the use of the table is not very convenient. Therefore, I have it swapped the columns and sorted by letters.
| Notation | Voltage, V |
| A | 3.2 |
| B | 6.3 |
| C | 4.0 |
| D | 10 |
| E | 16 |
| F | 20 |
| G | |
| H | |
| I | 1.0 |
| J | 50 |
| K | 63 |
| L | 80 |
| M | 2.5 |
| N | 100 |
| O | |
| P | 125 |
| Q | 160 |
| R | |
| S | 40 |
| T | 350 |
| U | 450 |
| V | 500 |
| W | 250 |
| X | 315 |
| Y | 400 |
| Z |
And, here, an example of a capacitor, the voltage designation of which is made according to the first system:
This capacitor has a capacitance of 4.7 nF (this is easily determined). The voltage of the capacitor is 100 V (the letter "N" at the beginning of the notation). The photo of the capacitor was sent by Igor Vitalievich K. I publish this photo without his permission. And, nevertheless, Igor Vitalievich - thank you for your contribution to the common cause! I'm sure people will thank you.
And here are some examples of designations, made according to the "Soviet" scheme. These capacitors were installed in the same blocks of automatic telephone exchanges (telephone exchange), but different year of release, respectively, of different equipment:
Here it is immediately evident that this capacitor has a capacitance of 47 nF and is designed for a voltage of 250 V.
What does the Russian capital letter "P" mean at the beginning of the notation in the first line - I do not know. Next is the designation of capacity: "47n". Here without questions.
The second line "black in Russian" tells us about the tension. What does the last "1" symbol in the line mean? I do not know either.
The next photo shows exactly the same capacitor, but with a different designation:
Here, the nominal capacitance of the capacitor is also easily guessed - "47n". Knowing that this is a "Soviet" designation, the next letter "J" also turns into a deviation - ± 5.0%.
But further on comes the Unified State Exam (Unified State Exam, that is, "guessing"). It can be safely asserted that I passed this exam for a thin c-grade, since besides the first letter "W" in the second line, I do not know what the remaining "MNP" means.
The letter "W" indicates a nominal voltage of 250 V. This is determined from the table above.
The third exactly the same 47 nF capacitor at 250 V is like this:
Here, the nominal capacity, the deviation and the operating voltage are grouped together in one line. A private experience, obtained with the two previous capacitors, will not make a mistake. "Private" - because it is so in this particular case, when it is known in advance that these capacitors were on the same boards. And in general - yes, the mess in the notation is still one! Compare with the green capacitor sent by Igor Vitalievich K, and try to answer the question - what criteria do you have to consider that the first letter "N" in the designation of this capacitor is responsible for its voltage?
The second system has a two-symbol voltage code. That's just something to find and failed.
The voltage in this system can be denoted as: 1J, 2A, 2G, 2J, which corresponds to the voltage 63V, 100V, 400V, 630V.
These designations are also applied to metal-film (and, possibly, ceramic) capacitors.
But the voltage codes on tantalum capacitors I met only the second system. The first system has never been seen. Well, sometimes it happens that the tantalum capacitors indicate the voltage directly.
I specifically talked about tantalum capacitors. They tend to have a low voltage. I have seen many times when only one letter is indicated, for example, "D". In this case it is implied that it is preceded by the missing one. It's easy to guess that such a capacitor is rated at 20 V. Or instead of "1A" or "1E" it's just "A" or "E", which means that the capacitor is rated at 10 V or 25 V.
"E" = 25 V, "j" = 6.3 V
It's very easy to make a mistake by mixing "J" and "j". Be careful! Just think that a 10μF tantalum capacitor with a voltage of 63 V can not be less than a 10 μF capacitor and a voltage of 25 V. And besides, tantalum SMD capacitors for voltage over 50 V are not released yet.
But where the uppercase letter is indicated, for example, - "e", then you should understand that it must be preceded by a zero. That is, the full designation must be "0e", which corresponds to a voltage of 2.5 V.
"A" = 10 V, "C" = 16 V
In the table, I indicated the voltage for the "1T" code in parentheses. The code for this voltage I saw on the Internet only once, moreover, I saw it not in official documents. Perhaps this is a mistake, because according to the table of 50 V, the code "1H" must match. Moreover, the "2H" code corresponds to a voltage of 500 V.
You see that the table is not complete. Therefore, I appeal to all interested comrades - do not hesitate to send me information that is not available in the table. The only request: the information must be reliable. For example, it would be logical to set the "1H" cell to a voltage value of 5.0 V. But I did not do it, because I have not yet met this value. Therefore, let it be better in the cell there will be "nothing" than the erroneous value will be indicated.
The table of tolerances (manufacturing accuracy) is also relatively easy to find on the Internet. I'll duplicate it here so that you (and me too!) Do not dig the Internet in its search. Let it be all in one place.
Good day dear radio amateurs!
I welcome you on the site ""
Capacitors
I must say that capacitor, like a resistor, can be seen in many devices. Usually, simple capacitor – these are two metal plates and the air between them. Instead of air can be porcelain, mica or other material that does not conduct current. If the resistor passes a direct current, then it does not pass through the capacitor. And alternating current flows through the capacitor. Due to this property the capacitor is placed where it is necessary to separate the direct current from the variable.
Condensers are permanent, tuning, variable and electrolytic. In addition, they differ material between the plates and the external structure. There are capacitors aerial, mica, ceramic, film etc. The use of certain types of capacitors is usually described in the accompanying documentation for the circuit diagram. Some capacitors of constant capacity and their designation in the circuit diagram are shown in Fig.1.
The main parameter of the capacitor is the capacitance. It is measured at micro-, nano- and picofarads. On the diagrams you will find all three units of measurement. They are designated as follows: microfarads - mKF or mF, nanofarads - nf, H or p, picofarads - pF or pf. More often the letter designation of picofarads does not indicate either the circuits or the radio components themselves, i.e. designation 27, 510 means 27 pF, 510 pF. To make it easier to understand the capacitance, remember the following: 0.001 μF = 1 nF, or 1000 pF.
In domestic electronics, alphanumeric markingcapacitors. If the capacity is expressed as an integer, the letter designation of the capacitance is placed after this number, for example: 12P (12 pF), 15H (15 nF = 15 000 pF, or 0.015 mF), HMM (10 mf). To express the nominal capacity with a decimal fraction, the letter designation of the capacity unit is placed before the number: H15 (0.15 nf = 150 pF), M22 (0.22 mf). To express the capacitance of an integer with a decimal fraction, the letter designation of the unit is put between the integer and the decimal fraction, replacing it with a comma, for example: 1H2 (1.2pf), 4H7 (4.7nf = 4700pf), 1M5 (1.5 mcf).
The alphanumeric marking of capacitors is also used in foreign electronics. It has found wide application on capacitors of high capacity. For example, the inscription is 0.47 | iF = 0.47 μf. Do not forget the developers and about color marking, which may contain bands, rings or dots. Marked parameters: nominal capacity; factor; allowable voltage deviation; t temperature coefficient of capacity (TKE) and (or) rated voltage. You can determine the capacity using the following table.
Some examples of the color marking of permanent capacitors are shown in Fig. 2.
In addition to alphanumeric and color marking, way of digital marking of capacitors with three or four digits (international standard). When three-digit marking the first two digits indicate the capacitance in picofarads (pF), and the last digit indicates the number of zeros(here I draw your attention to the marking of capacitors with a capacity of less than 10 picofarads: the last figure in this case may be a nine) :
(in the error table, it should be: 100
– 10 picofarads – 0.01 nanofarad -
0.00001 mkf (!)
)
When coding with a four-digit number, the last digit also indicates the number of zeros, and the first three - capacity in picofarads (pF):
Some examples of the digital marking of capacitors are shown in Fig. 3.
Among a large variety of capacitors of constant capacity, a special place is occupied by electrolytic capacitors. Today you can often hear the name oxide capacitors, since they use an oxide dielectric. Such capacitors produce a large capacitance - from 0.5 to 10,000 microfarads. Oxide capacitors are polar, therefore, in principle circuits for them indicate not only the capacity, but also the sign "+" (plus), but on the condenser itself: in the foreign variant there is a sign "-", in the domestic obsolete - "+". In addition, the principal schemes indicate the maximum voltage at which they can be used. For example, the inscription 5.0 × 10 V means that a capacitor with a capacity of 5 μf should be taken for a voltage of at least 10 V.
Many beginners are afraid to apply capacitors to a higher voltage than indicated in the diagrams. And in vain! Take, for example, a device with a 9V power supply. Here it is necessary to use a capacitor for voltage not lower than 10V, but better - 16V. The fact is that the "food" is not insured against surges. And for capacitors sharp changes in the direction of increase are equated to death. Therefore, if you apply electrolyte to a voltage of 50V, 160V or even more, the device will not work worse! Unless the dimensions increase: the greater the capacitor voltage, the larger its size.
Oxide capacitors have an unpleasant property to lose capacity - to "dry up", which is one of the main reasons for the failure of radio equipment in long-term operation. Such an unpleasant feature in particular has domestic electrolytes, especially old ones. Therefore, try to put foreign new capacitors.
Producers and non-polar oxide capacitors, although they are rarely used. There is also tantalum capacitors, which differ in durability, high stability of performance, resistance to temperature increase. With a small appearance, they can have a large enough capacity.
The line applied to the body of the tantalum capacitor means a positive terminal, and not a minus, as many think.
Some varieties of oxide capacitors are shown in Fig. 4.
Feature tuning and variable capacitors there is a change in capacity when the axis is turned, which extends outward. Previously, they were widely used radios. It was the capacitor of variable capacity that your parents twisted for tuning to the desired radio station. Some trim and variable capacitors are shown in Fig. 5.
For tuning or variable capacitors, the diagram shows the extreme capacitance values that are created if the condenser axis is rotated from one end position to the other or rotated in a circle (as in a trimmer capacitor). For example, the inscription 5-180 indicates that in one extreme position of the axis the capacity of the capacitor is 5 pF, and in the other - 180 pF. With a smooth return from one position to another, the capacity of the capacitor will also smoothly change from 5 to 180 pF or 180 to 5 pF. Capacitors of variable capacity do not use today, as they were replaced varicaps - a semiconductor element whose capacitance depends on the applied voltage.
Instructions
If you have an electrical circuit in accordance with the old standard, then the capacity designations in which the comma is present, regardless of whether the fractional part is equal to zero, are always expressed in microfarads. For example: 0.015;
50,0. If the comma in the designation is not, then the capacity capacitor is expressed in picofarads, for example: 5100;
200.
On modern schemes, capacity capacitor, expressed in microfarads, is always denoted by the abbreviation "μ" (not "μF"). A comma can both be present and not present. For example: 200 microns;
0.01 μ. The capacitance denominations, expressed in picofarads, did not undergo changes during the transition to the new standard.
A slightly different way of indicating capacitance is used when marking the bodies of the capacitors themselves. The designation "pF" or the complete absence of the unit name indicates that the capacitance is expressed in picofarads. Microfarads are designated using the "μF" abbreviation. Nanofarads are denoted by the Russian letter "n" or Latin n. If a part of the digits is before this letter, and the other part is after, the letter itself is equivalent to a comma. For example, the designation "4n7" read as "4.7 nanofarad".
In miniature capacitorx (including form factor SMD) capacity is denoted by special codes consisting of numbers and letters. When decrypting them, follow the document, located at the link given at the end of the article.
The coil of inductance is capable of accumulating magnetic energy during the flow of electric current. The main parameter of the coil is its inductance. Inductance is measured in Henry (HH) and is denoted by the letter L.
You will need
- Inductor parameters
Instructions
The inductance of a short conductor is determined by the formula: L = 2l (ln (4l / d) -1) * (10 ^ -3), where l is the wire length in centimeters, and d is the wire diameter in centimeters. If the wire is wound on the frame, an inductor is formed. The magnetic flux is concentrated, and as a result, the inductance increases.
The inductance of the coil is proportional to the linear dimensions of the coil, the magnetic permeability of the core and the square of the number of winding turns. The inductance of a coil wound on a toroidal core is L = μ0 * μr * s * (N ^ 2) / l. In this formula, μ0 is the magnetic constant, μr is the relative magnetic permeability of the core material, depending on the frequency), s is the cross-sectional area of the core, l is the length of the midline of the core, and N is the number of turns of the coil.
Related Videos
Sources:
- Inductor
The word " denomination"Has several similar meanings, used in various spheres of human life - both banking and philately. The nominal value, or denominationthe cost is a value determined by the issuer, which, as a rule, is indicated on a specific security or in a monetary denomination. At the same time, the real price of securities can significantly differ from its minimum value and is called the exchange value determined by the demand and supply for them.
Instructions
Money marks with a collection value also have a collector price, often many times more denominationprice. The same applies to coins made of precious metals - jubilee, issued to other dates - which initially are much more expensive than the value of the coin that is printed on it.
In philately denomination means designated on the postage sign denominationof the brand. The nominal value is easy to determine, but it is usually indicated in the currency of the state in the territory of which this brand will be distributed.
Usually, denominationthis is the price of a stamp in philately and is its price when sold at post offices. It consists of the amount of the established postal tariff charged for mailing, as well as other mail services and the price of the brand itself, which is called the franking value. In some cases denominationthe price is higher than the franking price: for example, a postal payment sign with an extra charge, if on the stamp other than the main one additional denomination.
There are several types of postal denominations. Astronomical denomination is the name of a very large denominationof the brand price, usually determined during hyperinflation in the state. So, for example, the cost of a brand in the RSFSR in the early 20-ies of the last century was 10 thousand rubles.
Additional denomination - is indicated on the mark after the "+" sign after the main brand value. This additional amount of postage is not related to the provision of postal services and is usually directed to charitable purposes, financing of public benefit shares, etc.
Identify denomination (resistance) resistor, attaching an ohmmeter to it. If there is no ohmmeter, connect the resistor to the current source, measure the voltage on it and the current in the circuit. Then calculate its value. In addition, the value of the resistor can be calculated by the color gamut or by a special code.
You will need
- To determine the nominal value, take an ohmmeter, an ammeter, a voltmeter, tables for decoding the denomination by codes and by colors.
Instructions
Determining the value of the resistor by direct measurements. Take an ohmmeter, connect it to the resistor terminals, measuring its resistance. For the correct measurement, set the sensitivity of the instrument. If there is no ohmmeter, assemble an electrical circuit that includes a resistor and an ammeter. Parallel to the resistor, connect a voltmeter. Then connect the circuit to the power source. Find out the current strength in amperes, using the ammeter and voltage readings in volts, using the voltmeter readings. Divide the voltage value by the current and get the nominal resistance of the resistor (R = U / I).
Determination of the resistor value by codes or multi-colored markings. Carefully consider the resistor. If it is marked with three digits, then the first two denote tens and ones, and the third power of the number 10, to which the number obtained from the code must be multiplied. For example, if the code is 873, then it means that the number 87 must be multiplied by 10 ^ 3. Obtain a nominal resistance of 87,000 Ohm or 87 kΩ.
Similarly, if the resistor is marked with four digits. The first three make up the number, and the last three - the degree of the number 10, to which it multiplies. For example, the value of the resistor 3602 is 360 10² = 36 kΩ.
If the resistor is marked with two digits and one letter, use a special labeling table for SMD resistors EIA, in which the first two digits will correspond to a numerical value of resistance, and the letter to a power of 10. For example, to find the value of a resistor labeled 40C, 255 multiply by 10² and get a resistance of 25.5 kΩ.